Who doesn’t love a grilled steak, washed down with a rich red wine? Um, your microbiome, the collection of microbes that live in your gut and play a major role in your risk of diseases such as obesity, cancer, and diabetes.
I’m often asked, especially by my friends in the Paleo community, why I recommend that people remove red meat for 21 days. Here are 15 reasons, along with the scientific evidence.
1. Meat consumption raises your estrogen levels.
Eating meat can aggravate estrogen dominance. In fact, women who consume more red meat and eat less fish and vegetables are thought to be more at risk for endometriosis. Overall, more meat consumption is associated with less fiber consumption, which raises bad estrogens and grows the wrong bacteria in your microbiome.
2. Women who eat red meat have a greater risk of breast cancer.
The association is greatest in postmenopausal women, with an increased risk of 22% among those who eat red and/or processed meat. Other studies suggest fried meat is the problem.
3. High red meat consumption increases your risk of colorectal cancer.
The mechanism is most likely an altered microbiome. In fact, the alterations in the gut microbiome can be used to screen for colorectal cancer.
4. Just the act of cooking red meat may increase your risk of cancer.
When you pan-fry or grill meat, it can release heterocyclic amines and polycyclic aromatic hydrocarbons, which are known to cause cancer in animals.
5. Many women lose weight when they switch to fish.
Women with the PPARG gene variant (like me) lose weight when they eat more fish (which is heavy on omega-3 fats) as opposed to red meat (which is heavy on saturated fats). This link has not been studied in men.
6. Meats are high in certain endocrine disruptors and persistent organic pollutants (POPs).
Meat, pork, and dairy expose you to multiple endocrine disruptors, including phthalates, HBCD, PBDEs, and Deca-BDEs. Persistent Organic Pollutants (POPs) are linked to lower adiponectin levels, obesity, diabetes, breast, and prostate cancer. Not surprisingly, POPs exposure shifts the microbiome in the wrong direction.
7. People who eat more fish (and less meat) have lower rates of breast and prostate cancer.
The Japanese, who eat a diet rich in fish oil and low in red meat, have among lowest rates in the world of breast cancer.
8. Red meat is associated with an increased risk of diabetes.
This link doesn’t prove causality, but is worthy of concern.
9. Red meat increases uric acid and creatinine.
This increases risk of gout and kidney problems.
10. Your liver will thank you.
Red meat increases hs-CRP, a marker of inflammation, and GGT, a marker of liver damage.
11. The fastest way to fatten an animal is to feed it grain.
By extension, the fastest way to fatten a human is to feed him or her grain-fed meat.
12. Meat can be contaminated with superbugs, which can trigger food-borne illness.
In fact, 55% of ground beef sampled by the Environmental Working Group has been found to be contaminated.
13. Red meat consumption is rising fast in the US and worldwide, and contributes to the rise of greenhouse gases and water shortages.
You probably know that one pound of red meat requires 2,500 gallons of water versus 23 gallons of water to produce a pound of lettuce.
14. There are no data as of this writing to show that grass-fed meat is better for your estrogen levels.
An animal is considered grass-fed, according to the USDA Grass Fed Marketing Claim Standards, when grass and forage are the “feed source consumed for the lifetime of the ruminant animal, with the exception of milk consumed prior to weaning. Animals cannot be fed grain or grain by-products and must have continuous access to pasture during the growing season. Hay, haylage, baleage, silage, crop residue without grain, and other roughage sources may also be included as acceptable feed sources. Routine mineral and vitamin supplementation may also be included in the feeding regimen.”
So … grass fed cows can still eat silage and baleage (whatever that means), and crop residue? And what exactly is in crop residue? You get my point. Grass-fed may not be what you think it is.
15. Grass-fed is better but not great.
Cooking reduces but does not eliminate the potential for exposure to growth promoters in ground beef. To be fair, grass-fed meat contains a better ratio of omega-6 to omega-3 fats, but data are lacking to show that grass-fed meat is better for your estrogen levels, risk of cancer, and weight gain.
In the absence of robust data, I recommend taking a periodic break from red meat and seeing how your body responds. And to learn more about how to take care of your microbiome, reset your hormones, and heal your metabolism, check out my new book, The Hormone Reset Diet.