The ketogenic diet, which people commonly call the keto diet, focuses on high fat foods and includes few to no carbohydrates. This approach may have several health benefits. Some evidence suggests that for some people, it may be a more effective weight loss plan in the long term than a low fat diet.

If a person eats a variety of healthful whole foods on the keto diet, they may find that they have very few, if any, nutritional deficiencies.

However, some supplements can help with the discomfort that can occur as a person's body adjusts to a keto diet. They can also help a person get the right amount of fats in their diet.

In this article, we look at seven supplements that may be useful for people on the keto diet.

Why take supplements on a keto diet?

A person on a keto diet can use supplements to fill in any nutritional gaps.

Some supplements, such as medium chain triglyceride (MCT) oil and omega-3 fatty acids, can increase the effectiveness of the keto diet and help people achieve the intended ratio of fat in their diet.

As the keto diet limits or eliminates many different foods, people who follow this diet can also use supplements to fill in any nutritional gaps. Magnesium, electrolytes, and fiber may be especially important.

Adjusting to extreme carbohydrate restriction can cause uncomfortable side effects because the body takes time to get used to making ketones and using this new source of energy.

The body usually burns carbohydrates for energy, but when a person eats few to no carbs on the keto diet, the body must get its energy from other sources. So, the body burns fat and turns it into ketones, which it can then use for energy. This process is called ketosis.

People often refer to the side effects of the diet as the "keto flu." Those beginning this diet may experience:

Certain supplements, such as electrolytes, digestive enzymes, and L-theanine, may help minimize these symptoms.

The following supplements may be helpful for people on a keto diet:

1. Medium chain triglyceride oil

Medium chain triglyceride oil, or MCT oil, is a type of fatty acid that occurs in coconut oil. The liver metabolizes these fats, transforming them into a source of fuel.

A 2018 study found a "clear ketogenic effect" when people took supplemental MCTs. MCTs may also help a person lose more weight, according to some research.

MCTs are not in many other foods, so taking a supplement can allow a person to get the potential benefits of these fats.

MCT oil is liquid at room temperature. People can mix it into foods or smoothies, or they can take it alone. A standard dose is 1 teaspoon. People should try this to start because a higher initial dose, such as 1 tablespoon or more, may induce diarrhea.

2. Magnesium

Magnesium is a mineral and electrolyte that is abundant in the body. The body needs magnesium for many different processes, including food metabolism, transmission of nerve signals, balance of fluids, maintenance of bone and muscle health, and more.

Although a few keto friendly foods, such as nuts and spinach, are high in magnesium, the diet is low in other magnesium rich foods, including whole grains, fruit, beans, and dairy products.

If a person is not getting adequate magnesium from foods while following the keto diet, they may need a supplement. A supplement may also be beneficial for those experiencing constipation.

Some evidence suggests that many people are at a high risk of magnesium deficiency due to chronic diseases, medications, and decreases in food crop magnesium levels.

Magnesium supplements are available in different forms. The Office of Dietary Supplements (ODS) state that the body may absorb some types — including magnesium aspartate, citrate, lactate, glycinate, and chloride forms — more readily than others. However, a doctor may recommend a specific form of magnesium to meet a person's needs.

High doses of magnesium can cause diarrhea. Therefore, a person should start with the lowest dose on the package, which may be 100–200 milligrams (mg) per day.

If no diarrhea occurs, a person may gradually increase the dose, although they should not take more than 400 mg per day unless a doctor advises a higher dose.

3. Electrolytes

As the body adjusts to a keto diet, the kidneys may excrete more water. This increased excretion can cause the body to lose vital electrolytes, which include not only magnesium but also potassium, chloride, phosphorus, and sodium.

Taking an electrolyte supplement can help rebalance the levels of these minerals. Electrolyte supplements vary in their mineral content, so it is important for a person to read labels to be sure that they are not getting too much of these minerals. Most contain a combination of calcium, potassium, and magnesium.

A keto friendly supplement should contain no sugar or sweeteners.

Alternatively, a person may wish to try adopting the following practices to get the three main electrolytes:

• taking a magnesium supplement daily
• adding some extra salt to the diet or consuming beef or chicken broth daily
• eating potassium rich, keto friendly foods, such as avocado or cooked spinach, every day

4. Fiber

Fiber supplements may help with constipation during a keto diet.

Fiber is the indigestible part of plant foods, and it is important for keeping the digestive system healthy.

Without enough fiber, a person may become constipated. People should get 25–31 grams of fiber per day, depending on their age and sex.

Many keto friendly foods, including nuts, seeds, avocado, and leafy greens, contain fiber. However, if a person focuses on meat, seafood, eggs, and dairy, they may not get enough fiber on the keto diet.

Fiber supplements can be helpful if people find that they become constipated while following the keto diet. They should look for a keto friendly formula that does not contain sugar.

It is also important to drink plenty of water, which helps keep digestion running smoothly. Taking fiber supplements without adequate water intake could make constipation worse.

5. Omega-3 fatty acids

Omega-3 fats are a type of polyunsaturated fatty acid (PUFA). Omega-3s are present in high amounts in some fatty fish and eggs, and they also occur in plant form in some nuts and seeds.

Studies show that consuming enough omega-3s can have health benefits, including helping prevent weight gain. The ODS state that many people could benefit from a higher intake of omega-3s.

The other type of PUFA, omega-6, occurs in many conventionally raised, grain-fed meats. Omega-6s are also in some vegetable oils, including corn and cottonseed oil.

One study found that among people following a ketogenic Mediterranean diet, those who ate more omega-3s experienced positive effects on their insulin, triglyceride, and inflammation levels.

Omega-3 levels may be higher in meats that come from grass-fed or pasture raised animals, as well as in eggs from pasture raised or vegetarian-fed hens. If a person on the keto diet does not eat grass-fed meats or seafood, they may want to consider an omega-3 supplement.

Omega-3 supplements vary in their dosage and origin. Some come from fish oil, krill oil, algae, flaxseed, or other natural omega-3 sources. A person should follow the dosage directions on the product.

People who take medications that affect blood clotting, such as blood thinners, should ask a doctor before using omega-3 supplements. People who are allergic to fish or shellfish should avoid supplements that contain fish oil, krill oil, or other fish based ingredients.

6. Digestive enzymes

The gut uses enzymes to break down different parts of foods during digestion. If a person who is switching to a keto diet ate a large number of carbs previously, they might find that they have trouble with the change.

Symptoms such as bloating, nausea, fatigue, and constipation are common because of the high amount of fats that a keto diet requires.

Digestive enzymes could help alleviate some of these symptoms. Many of these supplements contain several different types of enzyme, but it is important to choose one that contains lipase, which is the enzyme that breaks down fat.

Supplements that contain proteases and peptidases are also a good choice, as these break down protein.

In most cases, a person will take their digestive enzymes with a high fat meal or a few minutes before eating. They should always follow the dosage directions on the product and look for those that are keto friendly.

7. L-theanine

L-theanine supplements may help improve sleep quality.

L-theanine is an amino acid that is difficult to obtain from foods. The only known good source of l-theanine is green or black tea, but the amounts may vary depending on the type of tea and how a person brews it.

Studies show that taking this supplement may help improve sleep quality, decrease anxiety, and improve mental cognition. As a result, it could be an excellent option if a person experiences mental fog or trouble concentrating as they transition to the keto diet.

L-theanine supplements are available in pill or powder form. There is no recommended dosage, but many products suggest 100–400 mg daily. Alternatively, people may choose to drink unsweetened tea, particularly green tea, which contains natural L-theanine.

Buying supplements:

MCT oil
magnesium
electrolytes
fiber
omega-3
digestive enzymes
l-theanine

Summary

A range of supplements can help people on a keto diet by improving the effects of the diet, preventing nutrient deficiencies, and easing some of the side effects of cutting out carbohydrates.

The keto diet has health benefits for many people, but it may not be safe or sustainable for everyone. People who have diabetes or other health conditions should ask a doctor before making any dietary changes.

According to a 2019 study, allulose has "the bulk and the mouth fill of table sugar with reduced caloric content," making it an attractive sweetener. This study also suggests that scientists need to carry out more high quality research to confirm the long term safety and effectiveness of sweeteners, such as allulose.

Continue reading to explore the benefits and risks of adding allulose to your diet.

What is allulose?

Allulose is a lower calorie alternative to everyday sugar.

Allulose is a type of sugar that resembles fructose, which is the sugar that occurs naturally in fruit.

It is available in a granulated form and looks like everyday sugar. The scientific name for sugar is sucrose. Allulose is a low calorie sweetener that has 70% of the sweetness of sucrose.

According to the Food and Drug Administration (FDA), allulose provides about 0.4 calories per gram (g), which is significantly lower than the 4 calories per g in sugar. In addition, the body absorbs allulose but does not metabolize it into glucose, so it is virtually calorie free. According to the FDA, allulose has little to no effect on blood glucose or insulin levels.

Scientists can produce allulose in the laboratory, but it is also found naturally in some foods, such as dried fruits, brown sugar, and maple syrup.

Other names for allulose include psicose, d-psicose, d-allulose, or pseudo-fructose.

Is allulose good for you?

Allulose contains fewer calories than sugar and appears to have no effect on blood glucose levels. This means it could be a healthful alternative to sugar.

Doctors agree that sugar is a significant contributory factor to obesity. Obesity has associations with metabolic disorders, such as diabetes, high cholesterol, and cardiovascular diseases. Substituting high caloric sugars with a low calorie alternative, such as allulose, may help control obesity rates.

A small-scale study from 2015 suggests that allulose may have benefits for type 2 diabetes and obesity. The researchers report that allulose may help to control glucose levels and improve insulin resistance.

Much of the research into the effects of allulose have used animal models. In one human study, researchers looked at whether allulose could help reduce body fat, affect blood cholesterol, and affect markers of diabetes.

The results showed that those who consumed a high dose allulose beverage had significant decreases in body fat percentage, body fat mass, and body mass index (BMI) compared with those taking a placebo.

Researchers used CT scans to examine changes in the participants' abdominal fat area. At the end of the study, the people who consumed the high dose allulose drink had a significant decrease in total fat areas compared with those taking a placebo.

The study also reported that allulose had little effect on the levels of fat in people's blood. Levels of triglycerides, total cholesterol, and low density lipoprotein (LDL) cholesterol were unchanged in all groups.

The study also found no differences in the markers linked with diabetes, including fasting blood glucose, glycated hemoglobin, blood glucose, and insulin levels between the allulose and placebo groups.

The results of this study show that replacing sugar with allulose may offer potential benefits for those who are overweight or obese. Only a small number of volunteers participated in this study, so researchers need to carry out further studies in a more diverse study population to confirm these results.

How to use allulose

The FDA have approved of the use of allulose in many frozen desserts.

Allulose is not as sweet as sugar. People replacing sugar with allulose may find they need to use more allulose to achieve the same amount of sweetness they would get from sugar and other sugar substitutes.

The FDA have approved the use of allulose in:

• selected bakery products, such as sweet rolls, cakes, and pastries
• nonalcoholic beverages
• cereals
• chewing gum
• confections and frostings
• frozen dairy desserts, such as ice cream, soft serve, and sorbet
• yogurt and frozen yogurt
• salad dressings
• gelatins
• pudding and fillings
• hard and soft candies
• jams and jellies
• sweet sauces and syrups
• fat based cream
• medical foods

Possible side effects

According to the FDA, people may experience some abdominal discomfort from consuming large quantities of allulose, but this side effect is not toxic and usually temporary.

In one study, researchers investigated the possible side effects of consuming allulose occasionally or regularly. People reported abdominal side effects when consuming increasing doses of allulose, including:

• bloating
• abdominal pain
• diarrhea
• decreased appetite
• passing gas
• abdominal sounds

Allulose vs. alternatives

Allulose is a type of sugar that is found naturally in certain foods.

Other sugar substitutes that people use include:

• stevia
• aspartame
• saccharine
• sucralose
• neotame

Except for stevia, these sugar substitutes are not natural. Manufacturers make aspartame and neotame by combining two amino acids (protein building blocks found naturally in the body) and make sucralose from sucrose or table sugar.

The FDA has approved these sweeteners for use in humans and classified them as generally recognized as safe. Many manufacturers of beverages, dietary products, drugs, mouthwashes, and cosmetics use these low and no calorie sweeteners instead of sugar.

Manufacturers claim that artificial sweeteners can help people control hunger and appetite, lose weight, and manage diabetes. Not all scientists agree, but sweeteners are among the most researched ingredients in the food supply. Numerous medical associations and international regulatory bodies have deemed them safe when consumed in usual amounts.

Can you use allulose in a keto or paleo diet?

A person following a paleo diet can eat allulose that occurs in unprocessed foods.

The paleo diet consists of eating vegetables, fruits, nuts, roots, meat, and organ meats and excludes any highly processed foods.

People following a paleo diet can eat allulose, but only if they consume it from natural, unprocessed food.

Dried fruits, brown sugar, and maple syrup contain allulose.

The keto diet is very low in carbohydrate, moderate in protein, and very high in fat. Allulose is a carbohydrate, but it does not provide calories or raise blood glucose compared with sucrose and is keto compatible.

Summary

Doctors suggest that sugar is one factor that contributes to obesity. Lowering the amount of sugar a person eats and substituting sugar with low or no calorie sweeteners are two ways to help prevent obesity.

Compared with sugar, allulose is a low calorie carbohydrate. Some researchers suggest that allulose can help control weight and diabetes. People following the keto diet can use allulose to replace sugar.

People are searching for affordable and safe sweeteners to replace sugar. Eating a large amount of allulose may cause digestive discomfort, but there are few other known side effects. The FDA has approved other sugar substitutes, such as stevia, aspartame, and sucralose, as safe when used in moderation.

If a person wishes to try allulose or other sweeteners, they are available to purchase from drug stores, some supermarkets, and online stores.

Should we look to gene editing to manage obesity and diabetes?

According to the World Health Organization (WHO), in 2016, more than 1.9 billion adults worldwide were overweight, over 650 million of whom had obesity.

Being overweight or having obesity increases a person's risk of developing diabetes, heart disease, some types of cancer, and musculoskeletal problems, particularly osteoarthritis.

Weight management programs, which may involve nutrition education in combination with regular physical exercise, are one technique that people who are overweight or have obesity can use to help them work toward reaching a healthy body weight.

Prescription weight loss medications can also be part of a person's weight management plan, but these drugs come with a considerable risk of side effects.

In a 2016 article in the American Journal of Medicine, a team of doctors from Harvard Medical School in Boston, MA, reviewed the FDA-approved anti-obesity drugs available in the United States. Among the side effects were dizziness, nausea, constipation, insomnia, dry mouth, and vomiting.

"Anti-obesity drugs under development have been directed toward restriction of caloric intake by acting on the gastrointestinal tract or the central nervous system. However, most of these drugs have shown little efficacy accompanied by severe side effects," explain the authors of a new study that features in Genome Research this week.

The corresponding author is Yong-Hee Kim, a professor in the Department of Bioengineering at Hanyang University in Seoul, South Korea.

Kim's latest study focuses on avoiding the side effects associated with anti-obesity drugs and improving weight loss by exploiting how cells use their genetic code.

Interfering with gene expression

For their study, Kim and colleagues made use of a modified CRISPR gene editing tool called CRISPR interference (CRISPRi), which scientists at the University of California in San Francisco first developed in 2013.

Unlike traditional CRISPR, which seeks to alter the genetic code permanently, CRISPRi interferes with gene expression by inhibiting the production of proteins.

In a previous study, Kim developed a method to deliver genetically modifying agents to white fat cells, or adipocytes. In this paper, he explains that adipocytes are difficult cells to target with such gene editing tools.

Making use of a short peptide that specifically docks with white adipocytes, the team was able to deliver the CRISPRi components to 99% of cells in a cell culture model.

The protein that the researchers wanted to target was fatty acid-binding protein 4 (fabp4). Significant amounts of this protein are present in white fat and plasma, and scientists believe that it plays a role in sugar and insulin metabolism.

A previous study in Science Translational Medicine showed that reducing the levels of fabp4 in diabetic mice using an antibody resulted in improvements in blood sugar levels, as well as in fat and insulin metabolism.

Using their CRISPRi technology, Kim and his colleagues were able to reduce the expression level of fabp4 by up to 60%.

Next, the team used mice that were obese and diabetic, injecting them with their peptide-targeting CRISPRi twice a week for up to 6 weeks. The mice lost about 20% of their body weight during this time.

"No significant changes in food intake were recorded during the treatment period, indicating that the loss of body weight is not due to eating less," the authors write in their paper.

They also noted lower blood glucose levels, less inflammation, and improved biomarkers of nonalcoholic fatty liver disease.

Yet, promising results aside, the team urges caution.

"Despite its therapeutic potential, the translational research from a mouse model to patient in real life is yet a hurdle to overcome," the authors comment in the paper.

"In the in vivo experiments, the formulations were administered twice a week for up to 6 weeks. For humans, we cannot be sure whether a regimen of twice a week for up to 6 weeks could be applied," they continue, before concluding:

"Further studies regarding the translational research from a mouse model to human patient definitely need to be carried out before clinical use."

The study was small and only included five mice in each experimental group. However, it paves the way for further research into approaching obesity from a different angle than a traditional pharmaceutical approach.

In this article, we look at what a plant based diet is, the health benefits, and what nutritional considerations a person should make before switching.

What is a plant based diet?

Many people interpret a plant based diet as avoiding all animal products.

A plant based diet is a diet that involves consuming mostly or only on foods that come from plants. People understand and use the term plant based diet in different ways.

Some people interpret it as a vegan diet, which involves avoiding all animal products.

For others, a plant based diet means that plant foods, such as fruits, vegetables, whole grains, nuts, and legumes, are the main focus of their diet, but they may, occasionally, consume meat, fish, or dairy products.

A plant based diet also focuses on healthful whole foods, rather than processed foods.

Health benefits

Following a plant based diet offers many possible health benefits, including:

Better weight management

Research suggests that people who eat primarily plant based diets tend to have a lower body mass index (BMI) and lower rates of obesity, diabetes, and heart disease than those who eat meat.

Plant based diets are high in fiber, complex carbohydrates, and water content from fruit and vegetables. This may help to keep people feeling fuller for longer and increase energy use when resting.

A 2018 study found that a plant based diet was effective for treating obesity. In the study, researchers assigned 75 people who were overweight or had obesity to either a vegan diet or a continuation of their regular diet, which contained meat.

After 4 months, only the vegan group showed a significant weight loss of 6.5 kilograms (14.33 pounds). The plant based vegan group also lost more fat mass and saw improvements in insulin sensitivity, whereas those who consumed a regular diet with meat did not.

A 2009 study on more than 60,000 people also found that vegans had the lowest average BMI, followed by lacto-ovo vegetarians (those that eat dairy and eggs) and pescatarians (people who eat fish but no other meat). The group with the higher average BMI were nonvegetarians.

Lower risk of heart disease and other conditions

A 2019 study from the Journal of the American Heart Association found that middle aged adults who ate diets high in healthful plant foods and low in animal products had a lower risk of heart disease.

According to the American Heart Association, eating less meat can also reduce the risk of:

Diabetes prevention and treatment

Plant based diets may help people prevent or manage diabetes by improving insulin sensitivity and reducing insulin resistance.

Of the 60,000 people studied in 2009, only 2.9% of people on a vegan diet had type 2 diabetes, compared to 7.6% of those eating a nonvegetarian diet.

People eating vegetarian diets that included dairy and eggs also had a lower risk of type 2 diabetes than meat eaters.

Researchers have also looked at whether following a plant based diet can help treat diabetes. The authors of a 2018 review indicate that vegetarian and vegan diets could help people with diabetes reduce their medication needs, lose weight, and improve other metabolic markers.

The authors suggested that doctors might consider recommending plant based diets to people with prediabetes or type 2 diabetes. While veganism showed the most benefits, the researchers stated that all plant based diets would lead to improvements.

People wanting to try a plant based diet should try one that they think they can follow long term.

Foods to eat

People should focus on eating the following food groups when transitioning to a plant based diet:

Fruits

People who follow plant based diets can eat all types of fruit.

A plant based diet includes all fruits, such as:

Vegetables

A healthful plant based diet contains plenty of vegetables. Including a variety of colorful vegetables provides a wide range of vitamins and minerals.

Examples include:

Root vegetables are a good source of carbohydrates and vitamins. They include:

Legumes

Legumes are an excellent source of fiber and plant based protein. People can include a wide variety in their diet, including:

Seeds

Seeds are a great snack or an easy way to add extra nutrients into a salad or on top of a soup.

Sesame seeds contain calcium and sunflower seeds are a good source of vitamin E. Other seeds include:

Nuts

Nuts are a good source of plant based protein and vitamins, such as selenium and vitamin E.

Healthful fats

It is vital to consume polyunsaturated and monounsaturated fats, as well as omega-3 fatty acids. Plant based sources include:

Whole grains

Whole grains are an excellent source of fiber and help maintain stable blood sugar. They also contain essential minerals, such as magnesium, copper, and selenium.

Examples of whole grains include:

Plant based milk

If people want to reduce their dairy intake, there is a wide range of plant based milk available in grocery stores and online. These include:

Just make sure to choose unsweetened plant milk options.

Foods to avoid

Just reducing or eliminating animal products does not automatically mean a plant based diet is healthful. It is also vital to reduce or avoid unhealthful foods, such as:

• processed foods
• sugary foods, such as cakes, biscuits, and pastries
• refined white carbohydrates
• processed vegan and vegetarian alternatives that may contain a lot of salt or sugar
• excess salt
• fatty, greasy, or deep fried foods

Recipes to get started

The following recipes can help a person get started with a plant based diet:

Breakfast

Lunch

Dinner

Dessert

Snacks

Considerations

Before starting a plant based diet, people should ensure they take steps to get enough of the following nutrients:

Vitamin B-12

Vitamin B-12 is an essential nutrient for blood and cell health. B-12 deficiency can lead to anemia and nerve damage. B-12 is present in many animal products but not in many plant based foods.

People who eat a vegan or even a vegetarian diet could consider taking a B-12 supplement or consume products fortified with B-12. Foods include some cereals, plant based milk, and nutritional yeast. Nutritional yeast is available for purchase online.

Iron

People following a plant based diet may have to ensure they get enough iron in their diet, as it has lower bioavailability in plants than meat.

Plant based foods that are a good source of iron include:

• kidney beans
• black beans
• soybeans
• spinach
• raisins
• cashews
• oatmeal
• cabbage
• tomato juice
• dark leafy greens

Make sure to combine citrus and other vitamin C sources with plant based sources of iron to increase absorption.

Protein

Some people may have concerns about getting enough protein from a plant based diet. However, there is a wide variety of plant based sources of protein, including:

• lentils
• chickpeas
• quinoa
• beans, such as kidney, pinto, or black beans
• tofu
• mushrooms
• nuts
• seeds

Consuming proteins from a variety of food sources can help provide all the necessary amino acids for good health. For example, people could add a handful of seeds or a spoonful of hummus to tofu or beans.

Omega-3 fatty acids

A person following a plant based diet may wish to consider taking an omega-3 supplement.

Omega-3 fatty acids are essential as they help reduce inflammation, memory loss, and other chronic conditions, such as heart disease. The two primary omega-3 fatty acids are EPA and DHA.

Fish, seafood, and animal products, such as eggs are among the primary sources EPA and DHA.

While several plant based foods, such as walnuts, hempseed, and flaxseed, contain omega-3 ALA, research shows that the body is slow and inefficient at converting ALA to EPA and DHA. Some people are also genetically at risk for poor absorption of ALA.

Vegetarians exhibit lower levels of DHA and EPA in blood and tissue, which may increase inflammation, memory difficulties, brain fog, and other effects. People following a plant based diet might want to consider taking an omega-3 supplement. A range of plant based omega-3 supplements is available for purchase online.

Some dietitians advise vegetarians to reduce the amount of pro-inflammatory linoleic acid they consume. Soybean, corn, sunflower, and safflower oils contain linoleic acid.

Summary

Eating a diet higher in plant foods and lower in animal products can have many health benefits, including weight loss or maintenance and a lower risk of heart disease and diabetes.

If people want to make the switch to a plant based diet, they can start by gradually reducing their meat and dairy intake.

Eating an entirely plant based meal once a week, or swapping out one animal product for a plant based one, can be an excellent place to start.

People may also wish to speak to a doctor or dietitian before making significant changes in their diet.

Researchers say that red meat contains important nutrients, including protein, vitamin B-12, and iron. However, there is evidence to suggest that eating a lot of red meat can raise a person's risk of certain cancers, heart disease, and other health concerns.

This article looks at what the research says, official dietary recommendations, and what amount of red meat might be healthful.

The focus of this article is on the health impacts of red meat. It does not address the ethical and environmental arguments around the consumption of red meat.

How does red meat affect health?

Eating red meat may increase a person's risk of developing heart disease or cancer.

Specialists usually classify red meat as muscle meat from beef, pork, lamb, goat, or other land mammals.

On one hand, red meat is a good source of certain nutrients, especially vitamin B-12 and iron. The human body needs these nutrients to produce new red blood cells.

Red meat is also high in protein, which is necessary for building muscle, bone, other tissues, and enzymes.

However, some research has linked regular consumption of red meat to a number of health problems, such as heart disease, some cancers, kidney problems, digestive issues, and mortality.

To further complicate the issue, some studies suggest that the type of red meat a person eats makes the most difference.

Leaner cuts of unprocessed red meat, such as sirloin steaks or pork tenderloin, may be more healthful than other types. This is because they are unprocessed and do not contain excess salt, fat, or preservatives.

Processed red meats — including bacon, hot dogs, sausage, bologna, salami, and similar meats — appear to carry the highest risk of health problems.

Is red meat nutritious?

Red meat contains nutrients that are beneficial to health, including iron, vitamin B-12, and zinc.

Animal based foods, such as meat and dairy, are the main dietary sources of vitamin B-12. For this reason, people who follow a vegetarian or vegan diet may need to take supplemental B-12 in order to prevent B-12 deficiency anemia.

According to the United States Department of Agriculture, one 3.5-ounce (oz) or 100-gram (g) serving of uncooked ground beef contains:

• 247 calories
• 19.07 g of fat
• 17.44 g of protein
• 1.97 milligrams (mg) of iron
• 274 mg of potassium
• 4.23 mg ofzinc
• 2.15 micrograms of vitamin B-12

Many factors can affect the nutritional value of a specific piece of meat. For example, cuts from different parts of the animal vary in their calorie and fat content. Also, the way the farmer raised the animal, the animal's diet, and even the animal's age and sex can affect the nutritional value of the meat.

The National Institutes of Health (NIH) list some types of red meat as good sources of heme iron. Heme iron is only present in meat, poultry, and seafood. Nonheme iron occurs in plants and iron fortified foods, such as cereals and plant milks.

The NIH state that heme iron is more bioavailable, which means that the body can use it more easily. Although many people get enough iron from their diets, the NIH say that certain people are at risk of iron deficiency, including:

• infants
• young children
• people with heavy periods
• pregnant women

Heart disease and saturated fat

Nuts and beans are healthful plant based sources of protein.

Many different studies have suggested that eating red meat regularly can lead to a higher risk of heart disease. For years, experts have believed that the link between red meat consumption and heart disease is due to the saturated fat that is present in red meat.

The American Heart Association (AHA) claim that red meats generally have more saturated fat than other sources of protein, such as chicken, fish, or legumes.

They suggest that eating high amounts of saturated fat and any amount of trans fat can raise a person's cholesterol levels and increase their risk of heart disease. They therefore recommend that people limit the amount of red meat they eat and encourage people to choose lean cuts of meat.

That being said, red meat is not the primary source of trans fats in the Western diet. Packaged, processed, and fried foods tend to contain the most.

The AHA also explain that beans and legumes are heart-healthy alternative sources of protein. Examples include:

• pinto beans
• kidney beans
• garbanzo beans, or chickpeas
• soybeans
• lentils, split peas, and black eyed peas

A meta-analysis in the journal Circulation looked at 36 different studies. It concluded that replacing red meat with high quality plant protein sources — but not low quality carbohydrates — led to "more favorable" concentrations of fat in the blood.

The meta-analysis also found that there were not significant improvements in total cholesterol, low density lipoprotein cholesterol, high density lipoprotein cholesterol, or blood pressure between the red meat and animal protein diet groups.

Other studies have questioned the notion that saturated fat has links with heart disease. The authors of a review of heart disease risk state that researchers have exaggerated the role of saturated fat in the development of heart disease.

Also, a team of cardiologists wrote an article stating that the consumption of saturated fat does not clog the arteries or increase the risk of heart disease. Another article says that numerous analyses and reviews do not support the notion that eating saturated fat has links with heart disease.

All things considered, there is evidence both for and against saturated fats playing a role in heart disease. Research is ongoing.

Heart disease and trimethylamine N-oxide

Some studies have suggested that aside from the saturated fats debate, red meat still has other potential heart disease risks.

A recent study found that people who eat red meat regularly have higher levels of a metabolite called trimethylamine N-oxide (TMAO). Bacteria in the gut produce TMAO during digestion. It is a toxin that researchers have linked to an increased risk of heart disease death.

This study shows that people who ate red meat had triple the levels of TMAO compared with those who ate white meat or plant based proteins. However, their TMAO levels returned to normal around 4 weeks after stopping eating red meat.

Cancer and mortality

Some recent research suggests that eating red meat regularly could increase the risk of cancer or death. The findings of specific studies vary, however.

One 2015 paper states that red meat is "probably carcinogenic to humans," and that processed meat is "carcinogenic to humans." This is consistent with the World Health Organization's (WHO) classifications.

Specifically, the paper states that based on several large studies, people who ate more red meat were more likely to develop colorectal cancer. The risk was higher for both red meat and processed meat, though processed meat seemed to raise the risk more.

The research also found a higher risk of pancreatic and prostate cancer in those who ate red meat. Finally, those who ate more processed meat also had a higher risk of stomach cancer.

The authors say that meat processing methods, such as curing and smoking, can create cancer causing chemicals. This may be why researchers have linked processed meat with greater health risks than unprocessed meat.

Other research has also shown links between red meat and cancer. For example:

• One study tracked over 42,000 women for 7 years and found that higher consumption of red meat had links with a higher risk of invasive breast cancer. Conversely, women who ate poultry instead of red meat had a lower risk.
• Another study, which followed 53,000 women and 27,000 men, found that those who ate red meat, especially processed meat, had higher mortality rates over the course of 8 years. The participants did not have heart disease or cancer when the study began. Increases of "at least half a serving" of red meat per day had a 10% higher mortality risk.
• A large study that followed more than 120,000 men and women for 10 years found that only processed red meat, not unprocessed types, was associated with a higher risk of death.

Cooking methods and cancer

Using a different cooking technique can help reduce the levels of cancer causing chemicals in the meat.

When a person cooks meat at a high temperature, such as by pan frying it or grilling it over an open flame, certain chemicals form in the meat. These chemicals, called heterocyclic amines and polycyclic aromatic hydrocarbons, may cause changes in DNA that lead to cancer.

Exposure to these chemicals can cause cancer in animals, but experts do not know for certain that this also happens in humans.

The National Cancer Institute say that people can reduce their exposure to these chemicals by:

• not cooking meat, including white meat, over an open flame or on a very hot metal surface
• precooking meat in a microwave to reduce the time a person needs to cook it over high heat
• turning and flipping the meat regularly during cooking
• not eating charred portions of meat

Serving antioxidant rich vegetables, such as dark leafy greens, with cooked meats is another good way to support the body.

How much red meat is too much?

The guidelines for how much red meat is healthful vary from organization to organization.

The World Cancer Research Fund and American Institute for Cancer Research (AICR) say that if a person eats red meat, they should limit their intake to 3 servings per week. This would be equivalent to about 12–18 oz per week. They also say to eat little, "if any," processed meat.

They explain that meat can be a valuable source of nutrients, but that people do not need to eat meat — red or otherwise — to be healthy. In fact, they say that "people can obtain adequate protein from a mixture of pulses (legumes) and cereals (grains)."

The AHA are less specific in their meat recommendations. They say that people should cut back on meat and only eat it "once in a while," sticking to lean cuts and portions that are no larger than 6 oz.

However, not everyone agrees that people should avoid or limit red meat.

One article states that an "overzealous focus" on limiting red meat can lead people to eat less nutritious foods, such as highly processed junk foods. Also, because researchers have linked highly processed foods with numerous health problems, this may not be a positive trade-off.

The article also states that "unprocessed red meats are one of the best sources of high quality protein and make important contributions to nutrient intakes." They can also keep triglyceride levels lower than high carbohydrate diets do.

Summary

It is difficult to link one food or food group to health problems. This is because a range of other factors — including genetics, environment, health history, stress levels, sleep quality, lifestyle, and other dietary factors — may play a role in whether or not a person develops a specific condition or disease.

Still, the body of evidence claiming that eating high amounts of red meat, especially processed meat, could lead to health problems is growing.

Major health organizations, such as the AICR and the AHA, suggest eating more plants and less meat to help combat disease.

For this reason, people may wish to cut back on red and processed meat and to focus on foods that contain antioxidants and nutrients — such as fruits and vegetables — that can help prevent health problems.

It is important to remember that substituting red meat for processed, low quality carbohydrates can worsen insulin sensitivity, triglyceride levels, and overall health.

Finding light physical exercise exhausting may be a sign of future heart disease, says a new study.

The study, appearing in theJournal of the American Heart Association, looked at a participant pool of 625 individuals with an average age of 68 years.

The study team found that those who tired easily had an overall higher chance of developing cardiovascular disease.

First, the researchers calculated each person's 10-year risk of heart disease or stroke, using two different formulas.

Then, 4.5 years later, they assessed each participant with a test that consisted of "an extremely slow walk." Each person had to walk for 5 minutes on a treadmill set at a pace of 1.5 miles per hour. This exercise test was to examine their "fatigability."

After studied all the data, the researchers found that those who had higher cardiovascular risk scores from years ago were more likely to report that this simple physical task was exhausting.

"Even if you're exhausted because you have a newborn at home, this would be considered a very easy task," says study author Jennifer Schrack, an associate professor in the epidemiology department at Johns Hopkins Bloomberg School of Public Health in Baltimore, MD.

"It should be very light exertion. When people think the effort is more than very light, that's informative."

Risks of cardiovascular disease on the rise

Cardiovascular disease (CVD) is the leading cause of death worldwide, according to the World Health Organisation (WHO). While the current numbers of deaths due to CVD are high, experts believe they will increase over the next 15 years from 17.9 million in 2016 to over 23.6 million in 2030 around the world.

The American Heart Association (AHA) estimate there are 85.6 millions of people in the United States with more than one type of CVD, and approaching half of these adults are 60 years old or above.

CVD is a broad term that can refer to several different conditions. There are several ways to reduce the chances of developing CVD.

Eating well is a significant part of having a healthy cardiovascular system. This means consuming foods that are low in saturated fat, trans fats, and sodium. It is also vital to include fruits and vegetables, whole grains, fatty fish if not vegetarian or vegan, nuts, legumes, and seeds.

Also, it is crucial to be physically active. The WHO goal for maintaining a healthy heart is to do at least 150 minutes each week of moderate anerobic exercise, such as brisk walking.

Many people break this up into five 30-minute sessions each week. Alternatively, they can swap this regime for 75 minutes of high-intensity aerobic exercise, such as jogging or running.

Implications of the study

Dr. Salim Virani, a cardiologist at Michael E. DeBakey VA Medical Center and a professor of cardiology at Baylor College of Medicine in Houston, who did not participate in the study, voiced one criticism of this latest investigation.

He notes that the researchers did not measure "fatigability" at the beginning of the study, which would have allowed them to compare the two tests 4.5 years later.

However, Schrack says that people can use this symptom as a sign that they should pay more attention to their cardiovascular health and possibly make changes that could reduce their risk of CVD.

"People don't like to hear, 'Eat right and exercise.' These are two of the biggest pieces of public health advice, and we say it relat[ing] to almost every condition. But it's so true."

Jennifer Schrack

"People who are able to maintain their weight, maintain their activity level, tend to have [fewer] effects of fatigue and certainly less cardiovascular risk over time," concludes Schrack.

Prescription medication with omega-3 fatty acids may have cardiovascular benefits, new research suggests.

Triglycerides are fats in the blood. Some are naturally produced by the liver, while others come from calories that the body doesn't need to use immediately. The more calories a person takes in, the likelier they are to have a high triglyceride count.

Higher levels, calculated as above 200 milligrams per deciliter (mg/dl), can increase a person's risk of having a stroke or heart attack by causing a narrowing of the arteries.

Estimates suggest that around a quarter of the adult population of the United States may have triglyceride levels above 150 mg/dl.

Exceedingly high levels — above 500 mg/dl — can also result in inflammation of the pancreas, otherwise known as pancreatitis.

Thankfully, there are a few ways to reduce triglyceride levels. Getting regular exercise, reducing alcohol consumption, and eliminating sugar and refined carbohydrates can help, as can other steps to maintain a healthy weight, such as swapping saturated for unsaturated fats.

Turning to medication

Sometimes, these changes are not enough to make a substantial difference. If this is the case, a doctor will rule out conditions such as type 2 diabetes and hypothyroidism before prescribing medication for high triglyceride levels.

Currently, two triglyceride-lowering prescriptions exist, and both involve omega-3 fatty acids. One contains a fatty acid called eicosapentaenoic acid (EPA). The other combines EPA with a second fatty acid: docosahexaenoic acid (DHA).

Previous research had not compared the effects of these medications. But a recent review-based advisory from the AHA, published in its journal Circulation, has concluded that both are equally effective.

The researchers based their findings on an analysis of 17 clinical trials and found that "Treatment with 4 grams daily of any of the available prescription choices is effective," explains first study author Ann Skulas-Ray, Ph.D., from the Department of Nutritional Sciences at the University of Arizona, in Tucson.

Skulas-Ray also notes that these medications can be "used safely in conjunction with statin medicines that lower cholesterol."

Plenty of positives

The Food and Drug Administration (FDA) have currently only approved prescription omega-3 fatty acid medication to treat triglyceride levels that are extremely high, above 500 mg/dl.

But the authors of the current advisory found that a 4-gram daily dosage could reduce triglyceride levels of 200–499 mg/dl by between 20% and 30%. This would apply to the majority of people with high triglyceride levels.

The researchers also noted that the medication that contains both EPA and DHA did not increase levels of LDL cholesterol, the "bad" type, in people with triglyceride levels below 500 mg/dl.

They also found that people with very high triglyceride levels who took EPA-only medication combined with statin therapy experienced a 25% decrease in major cardiovascular events, including stroke and heart attack.

Avoid supplements

Skulas-Ray points out that people should not try to treat high triglyceride levels at home with nonprescription omega-3 supplements. "Dietary supplements containing omega-3 fatty acids are not regulated by the FDA," she explains.

"They should not be used in place of prescription medication for the long term management of high triglycerides."

In 2017, the AHA released an advisory citing a lack of evidence to support the claim that fish oil supplements could prevent cardiovascular disease in the general population.

The AHA have, however, noted that people who have experienced a heart attack or heart failure may benefit from the supplements.

Still, consuming omega-3 fatty acids in fish can reduce heart disease and stroke risk. The AHA recommend eating fatty fish, like mackerel, salmon, lake trout, and albacore tuna, twice a week.

Pushups are a type of strength building exercise. Though they mainly activate muscles in the arms and shoulders, they also engage muscles in the core and legs. Therefore, pushups are beneficial for building strength throughout the body.

This article focuses on the effects of daily pushups on the body. We cover the benefits as well as the potential risks. We also discuss whether or not people should do pushups every day.

Increased joint support

Benefits of pushups include increased joint support, muscle tone, and strength.

Pushups are particularly effective at strengthening the muscles around the shoulder joints.

The muscles and tendons in the shoulder area are responsible for keeping the upper arm bone in the shoulder socket.

However, it is important to increase the number of pushups gradually to build up sufficient strength in the muscles. Overloading weak muscles can result in muscle and tendon injuries.

Increased muscle tone and strength

There are several different variations of pushups, and each type activates the muscles in different ways.

A small 2015 study involving eight volunteers looked at the following pushup variations and compared their effects on different muscle groups:

• Standard pushup (SP): The hands are shoulder width apart and directly in line with the shoulders. The upper body, or trunk, lines up with the legs, and the body remains rigid throughout.

• Wide pushup: The distance between the hands is twice that of in the SP.
• Narrow pushup (NP): The hands are below the center of the breastbone, or sternum, with the thumb and forefinger of each hand touching.
• Forward pushup (FP): The hands are shoulder width apart but 20 centimeters (cm) in front of the shoulders.
• Backward pushup (BP): The hands are shoulder width apart but 20 cm behind the shoulders.

The study found the following:

• NPs resulted in the greatest activation of the triceps and pectoralis major muscles, or pecs.
• FPs and BPs resulted in the greatest activation of the abdominal and back muscles.
• BPs activated the largest number of muscle groups overall.

The authors conclude that BPs might be the most beneficial pushup variation for improving upper body condition and strength.

NPs are best suited to people trying to increase the size, tone, or strength of their triceps and pecs.

Improved cardiovascular health

Increased muscular strength may reduce a person's risk of cardiovascular disease.

Several studies have linked muscular strength to a reduction in cardiovascular disease risk.

A 2019 study investigated the link between the number of pushups a person can do and their risk of developing a cardiovascular health issue 10 years later. A total of 1,104 active, middle-aged males took part in the study.

The researchers found a significant difference between two groups of males; those who had been able to perform more than 40 pushups, and those who had been able to perform fewer than 10.

Males in the 40+ pushup group were 96% less likely to have experienced a cardiovascular problem than males in the 10- pushup group.

However, it is important to remember that this study included only active, middle-aged males. Further studies are necessary to determine if these associations are the same for females and for people who are older or inactive.

Risks

As with most exercises, pushups may increase the risk of certain injuries.

Many injuries result from using an improper technique. People should talk to a fitness instructor if they are unsure about how to perform the different variations of pushups.

Overall, the benefits of exercise tend to outweigh the risks. However, some potential risks of practicing daily pushups include:

Reaching a fitness plateau

People who repeat the same exercise daily will notice that it becomes less and less challenging over time. People refer to this as a fitness plateau. It indicates that the muscles are no longer developing.

To avoid reaching a fitness plateau, people should incorporate a wide range of exercises into their fitness routine. Doing so will activate many different sets of muscles.

People who are keen to maintain muscle may benefit from introducing aerobic exercise. A 2013 study found that people who do aerobic exercise tend to maintain greater muscle strength across their lifespan.

Ideally, a thorough workout routine should also incorporate the following types of exercise:

• core development
• balance training
• stretching

Back pain

Certain pushup variants, such as the BP and the FP, increase activation of the lower back muscles. This may lead to lower back pain and discomfort.

Pushups also cause temporary compression of the intervertebral joints in the spine. An intervertebral joint is the point at which two sections of backbone come together.

A cushion of tissue called an intervertebral disc separates each section of the backbone. Excessive weight bearing exercises may contribute to wear and tear of these discs, resulting in pain and stiffness.

People with existing back conditions should talk to a doctor before incorporating pushups into their fitness routine.

Wrist pain

Some people experience pain in the wrists when performing weight bearing exercises such as pushups. Most pain occurs along the back part of the wrist when a person bends the hand backward.

A 2017 study found that 84% of people experiencing pain along the back of the wrist in response to weight bearing had a physical abnormality within the wrist. Around 76% of these cases were due to a small ganglion cyst. The second most common cause of pain was a partial ligament tear.

It is not clear if these abnormalities were the result of repeated weight bearing exercises.

Nonetheless, people who experience wrist pain during pushups should see a doctor. They can offer advice on how to support the wrist during exercise. Alternatively, a doctor may recommend a different exercise technique.

Elbow injury

Fast pushups may cause elbow strain.

A 2011 study investigated the effect of pushup speed on elbow joints. The researchers tested three different pushup speeds: fast, medium, and slow.

The study found that faster pushup speeds resulted in greater forces on the elbow joints, ligaments, and other surrounding tissues. They concluded that faster pushups could increase the risk of injury to these structures.

The study also showed that slower pushup speeds resulted in greater muscle activation.

Overall, these findings suggest that slower pushups are safer and more likely to result in improved muscle development.

Summary

Doing daily pushups can help build muscle tone and strength in the upper body. Other potential benefits include improved cardiovascular health and better support around the shoulder joints.

However, practicing pushups every day does come with some risks. These include lower back pain, wrist pain, and elbow injury. People can reduce these risks by learning the proper technique for the pushup variations they want to incorporate.

People who choose to practice pushups every day should also try to incorporate other forms of exercise. This is likely to provide a greater overall health benefit than pushups alone.

Even taking a simple walk can make a difference to a person's longevity.

Researchers came to this conclusion after analyzing data from published research that had involved the use of wearable trackers to measure the physical activity in adults who were middle-aged and older.

A recent BMJ paper gives a full account of the systematic review and meta-analysis.

The analysis also reveals that sitting for more than 9.5 hours per day is linked to a significantly higher risk of early death.

The findings largely confirm those of previous studies on links between physical activity, sedentary behavior, and longevity.

According to the researchers, most health guidelines about minimum levels of exercise have relied mainly on studies that used self-reported levels of activity.

The researchers note that their new investigation is significant because they only included those studies that measured physical activity using accelerometers. These wearable movement sensors can track the amount and intensity of activity during waking hours.

Sedentary behavior and light exercise

The team also wanted to clarify the effect of sedentary behavior. The guidelines advise people to spend less time sitting, but they do not specify how much sitting is harmful.

Another question that the new study clarifies is the contribution of low intensity activity.

For example, the United States government's physical activity guidelines recommend a minimum of 150 minutes of moderate or 75 minutes of vigorous activity per week.

While the guidelines mention light activity as a good start to reaching this level and beneficial to health, the emphasis is mostly on moderate and vigorous activity.

Does this mean that light activity has less impact on health and longevity, especially for adults in their middle years and older, than moderate and vigorous activity?

"Answering these questions [has] huge relevance for health promotion," state two of the authors of ths new study, Ulf Ekelund and Thomas Yates, in an accompanying BMJ opinion article.

Ekelund is a professor at the Norwegian School of Sport Sciences and the Norwegian Institute of Public Health, both in Oslo, Norway. Yates is a professor of physical activity, sedentary behavior, and health at the University of Leicester in the United Kingdom.

What the researchers analyzed

For their study, Prof. Ekelund and colleagues set out to examine links between physical activity, sedentary behavior, and risk of death in middle-aged and older adults.

Their analysis included data on a total of 36,383 adults of minimum age 40 years and average age 62 years.

The data came from eight studies that had tracked activity using motion sensors for up to 1 week and had followed the participants after that for an average of 5.8 years.

The studies had categorized physical activity as light, moderate, or vigorous and had estimated the amount of daily time spent doing each.

The researchers give examples of light physical activity as walking, washing dishes, and cooking.

Moderate activity includes mowing grass, brisk walking, and vacuuming, while digging, jogging, and carrying heavy weights are examples of intense physical activity.

The team arranged the results into quarters, ranging from the 25% most active to the 25% least active participants.

Of the participants, 5.9% (2,149 individuals) died during the followup. The researchers used these deaths to calculate the risk of death for the most to the least active participants.

Any level of activity makes a difference

After adjusting the results for factors that could influence them, the team found that any level of activity — whether it was light, moderate, or vigorous — related to a significantly lower risk of death during the followup.

The 25% most active participants had a 60–70% lower risk of death compared with the 25% least active. There were around five times more deaths in the least active compared with the most active group.

In addition, sitting for a total of 9.5 hours a day or more, not counting time spent sleeping, was linked to a statistically significant raised risk of death.

The researchers suggest the findings reinforce that any level of physical activity — even light exercise that is within reach of most people — is beneficial.

They observe that the effect sizes in their results are about double the size of previous studies that have relied on self-reported data.

Prof. Jochen Klenk of Ulm University in Germany and Prof. Ngaire Kerse of the University of Auckland in New Zealand discuss the findings and the impact that wearable motion sensors are having on this type of research in a linked editorial.

They note that the introduction of wearable sensors has allowed researchers to collect more precise and objective measures of levels and amount of physical activity.

"But," they caution, "inconsistency and uncertainty remain, especially about the magnitude of any effects and the contribution to health of low levels of physical activity."

However, the analysis that went into the new findings drew on high quality studies, harmonized methods, and used data on more than 36,000 people. The total scope covered more than 240,000 person-years of followup and 2,100 events.

This gave the authors "sufficient statistical power" to enable them to "differentiate between different levels of intensity – including low intensity physical activity," note the reviewers.

Researchers used cell culture experiments to reveal that defects in the cells' mitochondria, along with exposure to certain types of fats, drive inflammation in type 2 diabetes.

Chronic inflammation is the root cause of many of diabetes' complications, including cardiovascular and kidney disease.

Until now, the scientific consensus has been that glucose drives inflammation in type 2 diabetes.

But new research counters this popular notion and points instead to high levels of lipids and defects in mitochondria — the tiny energy-reducing organelles inside cells.

Barbara Nikolajczyk from the Department of Pharmacology and Nutritional Sciences at the University of Kentucky Barnstable Brown Diabetes Center in Lexington is the lead author of the new study.

Nikolajczyk and her team started from the hypothesis that immune cells from people with type 2 diabetes would produce energy by breaking down glucose through the process of glycolysis.

Glycolysis is a series of reactions that turn glucose into energy. Other types of inflammation also rely on this process.

However, the results of the new research — appearing in the journal Cell Metabolism — disproved the scientists' premise.

Experiments reveal surprising results

"We exclusively used immune cells from human subjects for all of the work," Nikolajczyk explains.

She adds that she and her team have previously identified pro-inflammatory T cells with a profile specific to humans, which explains why animal models would not have been helpful for the current research.

The researchers compared samples from 42 people with obesity who did not have type 2 diabetes with samples from 50 people who had both obesity and diabetes.

The scientists excluded samples from people who were smokers, used insulin, had taken antibiotics or anti-inflammatory medication, as well as those who had a medical history of other inflammatory or autoimmune conditions.

Nikolajczyk and team isolated immune cells called CD4+ T cells and performed several cell culture experiments that revealed glycolysis does not drive chronic inflammation.

"[A]ctivated immune cells and purified CD4+ T cells" from people with type 2 diabetes are "strongly biased" towards glycolysis, write the authors. However, glucose starvation experiments designed to steer cells from people with type 2 diabetes "away from glycolysis and toward alternative fuel sources " did not normalize the inflammatory profile of T cells, as the researchers expected.

This unexpected result, explain the authors, shows that "glycolysis parallels, but does not fuel, [type 2 diabetes] inflammation."

Instead, the experiments revealed that T cells from people with type 2 diabetes had a range of mitochondrial defects. They also found that alterations in the "import or oxidation of fatty acids" trigger inflammation in healthy cells.

Nikolajczyk and colleagues conclude:

"Mitochondrial changes combine with fatty acid metabolites to activate inflammation."

Study may explain why treatments fail

The authors expand on the importance of their findings. They write that identifying the main driver behind obesity-associated inflammation is critical for preventing or treating metabolic disorders in people with obesity.

"Our data unexpectedly show that glucose, which drives inflammation in other contexts, is dispensable for type 2 diabetes-associated inflammation."

"Instead, partial defects in the cell's power plant, or mitochondria, fuel inflammation, but only in cells further stressed by the types of lipids that are elevated in obesity and type 2 diabetes," they explain.

Because current standard treatments for diabetes focus on glucose control, the surprising findings "raise clinical concerns that lipids will continue to drive inflammation, and thus metabolic dysfunction," even in diabetes patients with good glucose control.

"Aggressive blood glucose control to lower the risk of diabetic complications has been the goal for most people with type 2 diabetes for decades," stresses Nikolajczyk.

"Our data provide an explanation for why people with tight glucose control can nonetheless have disease progression."

Barbara Nikolajczyk