Why Meat Causes Inflammation

The anti-inflammatory effect of plant-based diets is about more than just the power of plants. It’s also the avoidance of animal foods. In my Care2 column last week, Dietary Treatment for Crohnís Disease, I profiled the extraordinary power of even a semi-vegetarian diet to calm inflammatory bowel disease. Weíve known for 14 years that a single meal of meat, dairy, and eggs triggers an inflammatory reaction inside the body within hours of consumption. This results in a stiffening of our arteries (you can see the arterial response curve in my 4-min. video The Leaky Gut Theory of Why Animal Products Cause Inflammation). Within 5 or 6 hours, the inflammation starts to cool down, but then what happens? Lunchtime! At that point we can whack our arteries with another load of animal products for lunch. In this routine, we may be stuck in a chronic low-grade inflammation danger zone for most of our lives. This can set us up for inflammatory diseases such as heart disease, diabetes, and certain cancers one meal at a time.

What exactly is causing the meat-induced inflammation? Inflammation is an immune response to a perceived threat, but whatís the body attacking? At first, scientists thought it might be the animal protein, which is thought to be the culprit in certain types of arthritis. However, similar inflammatory reactions were triggered by whipped cream, which is mostly just animal fat. After digging deeper, investigators discovered that after a meal of animal products one’s bloodstream becomes soiled with bacterial toxins known as endotoxins. No wonder there’s so much inflammation! But where are the endotoxins coming from?

Endotoxins come from bacteria. Where are there lots of bacteria? In our gut. Thus, researchers figured that maybe the saturated animal fat was causing our gut lining to become leaky, allowing our own bacteria to slip into our blood stream. Experiments on mice showed that indeed saturated fat made their guts leaky, so for years this was the prevailing theory as to why animal products caused inflammation within hours of consumption. Only recently did researchers realize this didn’t make any sense.

In my 2-min. video The Exogenous Endotoxin Theory, I illustrate the critical flaw to the leaky gut theory: the time scale. The rise in inflammation after a meal of meat, dairy, and eggs starts within just an hour of ingestion, but our gut flora aren’t in our small intestine–rather, twenty feet farther down in our large intestine. It can take food hours to get down there, so what was going on? If the bacterial endotoxins were not coming from our gut, maybe they were coming from the food.

For the first time ever, 27 common foodstuffs were tested and they found endotoxin equivalents in foods such as pork, poultry, dairy, and egg products, as well as certain fermented foods. Can endotoxins be cooked out of the meat? Find out in today’s NutritionFacts.org video pick (see above).

Saturated fat also appears to have other deleterious effects such as increasing the risk of heart disease (see Blocking the First Step of Heart Disease and Tolerable Upper Intake of Zero) and shortening the lives of breast cancer survivors (Breast Cancer Survival, Butterfat, and Chicken). For more on foods that fight inflammation, see my videos Fighting Inflammation in a Nut Shell and†Anti-Inflammatory Effects of Purple Potatoes.

In health,
Michael Greger, M.D.

Image credit: woodleywonderworks / flickr


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William C
William Cabout a year ago

Thank you.

W. C
W. Cabout a year ago


Jeanne Rogers
Jeanne Rogers1 years ago

Thank you for sharing.

Jeanne Rogers
Jeanne Rogers1 years ago

Thank you for sharing.

4 years ago

My body would be dead and buried if I had 'gone vegan'

It's bad advice because there is NO single diet that is right for everyone!
Use common sense, moderation and balance when choosing a diet that is right for YOU.

We all have to eat the foods that supply the nutrients that our own bodies require.

Accept it and deal with it.

Baal P.
Baal P.4 years ago

Save your body, go VEGAN.

Tim C.
Tim C4 years ago


Nicole Bergeron
Nicole Bergeron4 years ago

Rosemary, while not vegan (me that is), you can try to change to flavor of the foods you had, which can also change the texture if done right, such as boiled and mashed cauliflower.

If that fails, the best thing you can do to make sure you get everything you need is go see a nutritionist and explain your problem to them. though there are diets out there for people who have to take certain meds that prevent them from eating leafy greens because they are high in vitamin K.

you'll have to find food replacements that equal, or greater, amounts of Protein, Thiamin, Riboflavin, Niacin, Magnesium and Phosphorus, and a very good source of Dietary Fiber, Vitamin C, Vitamin K, Vitamin B6, Folate, Pantothenic Acid, Iron, Potassium and Manganese that are in cauliflower. You can search out individual foods or do a mix and match to create dishes that have equal or more amounts. It is possible to be vegan with a wide plate without cauliflower

A website that can help is yummly.com, while not a vegan website, you can chose the ingredients and diet type (vegan, vegetarian, lacto-vegetarian, ect) along the same, and there are 1,206 without cauliflower that are vegan (if you main search with cherry tomato like I did), plus you'll be able to add the leafy greens you can't have in the leave out list, and should still get a decent amount. As well as choose different main ingredients in the main search bar to mix it up.

Hope this helps.

Rosemary H.
Rosemary H4 years ago

Sorry, got cut short....

I don't for one minute imagine that I get the same nutrients from free-range meat and eggs, plus fish, as I would do from the plants I simply cannot eat, however I'm still healthy althougth I'm longer a youngster.

Rosemary H.
Rosemary H4 years ago

Well, I was going to explain that we evolved to be omnivores... but it can wait for another time. Dale and Marilyn have both made a lot of other good points, but I have a question I would like some vegans to answer. How can anyone with the problem I have go vegan successfully, please?

I do not want to eat anything that could be GM or GM contaminated. I also try to stay clear of palm oil because of the destruction of rain forests. So far I guess you agree...BUT... I can not swallow any form or leafy green veggie, or related plants such as cauliflower. I was force fed on them as a child with the result that if I get even a speck of this stuff smaller than my little finger nail in my mouth, it brings about a violent retching reaction! It is truly horrible, and there is No Way that I could ever get enough of this stuff down myself to make the smallest difference to my health! Instead I would probably send my stress levels sky-high!

Obviously I don't want to eat processed meat from animals who have suffered an appalling existence in factory farms. I love free-range eggs, and I can make out a big case for cattle and sheep grazing in conservation projects. This is an aspect of meat-eating that never seems to get enough attention. I can eat certain types of fruit and veggies if they taste completely different from the stuff I was force fed on. But if I was to turn vegan, what could I live on to put sufficient variety into my diet?

I don't for one minute imagine that I get th