In This Article
Is Meat Really Back on the Menu?
We’ve all heard we should stop eating meat, and also that we should eat more meat! What are we to believe?
A controversial study suggesting new dietary guidelines around meat was recently published in Annals of Internal Medicine, suggesting there was low evidence that red meat or processed meats were harmful, so adults should continue current consumption of both processed meats and red meat.1
Could it be true that red processed meats aren’t harmful? This study flies in the face of decades of cumulative studies linking processed meats and excess red meat consumption to cancers and other health concerns.
Backlash from the research community has been fierce. Dr. Frank Hu (chair of the Department of Nutrition at the Harvard T.H. Chan School of Public Health) fired back, saying:
“This new red meat and processed meat recommendation was based on flawed methodology and a misinterpretation of nutritional evidence, the authors used a method often applied to randomized clinical trials for drugs and devices, which is typically not feasible in nutritional studies.”2
A study in the prestigious Journal of American Medicine (JAMA), published just two months after the flawed study in the Annals of Internal Medicine, confirms the link between red meats, processed meats, and cardiovascular risk.3,4
With links between processed meat consumption and increased risk of cardiovascular disease (CVD) and all-cause mortality well-established, this study evaluated risks associated with consumption of unprocessed red meat, poultry, or fish.3
This study evaluated the diets of almost 30,000 adults for 31 years and concluded that: higher intake of processed meat, unprocessed red meat, or poultry, but not fish, was significantly associated with increased risk of incident CVD, whereas higher intake of processed meat or unprocessed red meat, but not poultry or fish, was significantly associated with increased risk of all-cause mortality.
A 2017 systematic review and meta-analysis finds red and processed meat consumption to be associated with higher risk of overall colorectal cancer.5 A 2015 meta-analyses of 10 studies shows red meat and processed meat consumption convincingly increases colorectal cancer risk by 20-30%.6
Does Eating Less Meat Increase Longevity?
The amount of meat eaten by traditional cultures was not nearly as much as we might think. According to Dan Buettner, who wrote a series of books on centenarian cultures around the world—called blue zones—the longest-lived folks ate about two ounces of meat or less about five times a month, with about 10% of total calories being animal protein.8
One meta-study of six studies on longevity and meat consumption concludes that a diet with very low meat intake is associated with greater longevity.7 They found:
- A very low meat intake is associated with significant decrease in risk of death in four studies, a nonsignificant decrease in risk of death in the fifth study, and virtually no association in the sixth study.
- Two studies showed low meat intake significantly decreased mortality risk.
- The longer a low meat diet was adhered to, the greater the decrease in mortality risk, showing an average 3.6 year increase in life expectancy.
History of Seasonal Meat Eating
Each winter, foods available in the Northern Hemisphere shift us to a higher-fiber, higher-fat, and higher-protein diet.
Seasonal foods, such as meats, nuts, seeds, grains, and legumes, require a stronger digestive system. This is provided by a new stable of winter microbes better able to digest winter foods. To break down these foods, the stomach is required to produce more hydrochloric acid. Hydrochloric acid helps break down anti-nutrients in grains and proteins in meats.
Digesting winter food also keeps us warm. Digestive acids, along with winter-based fermented foods (made with warming lactic acid fermentation), provide a welcome increase of internal heat.
During summer, the body could be overheated by the same diet and digestive microbes. Summer foods are cooked on the vine and much less digestive heat is required to break down the leafy greens, fruits, and berries of summer, which are cooling.
Eating cooler, easier-to-digest foods in summer allows us to not overheat. In winter, harder-to-digest foods boost digestive acids, provide a better winter fuel reserve, internal heat, and much-needed insulation.
The takeaway here is that we should seek out easy-to-digest foods in summer (fruits and vegetables cooked on the vine) and harder-to-digest, denser, heating, and insulating foods in winter.
Eat Less Meat in Summer
In traditional cultures, during winter months, animal protein intake would go up—as hunting may have been one of the only sources of food in more extreme climates. During summer, animal protein intake should decrease, while plant-based foods should be eaten in greater quantities.
Here in the West, many still eat meat two to three times a day, which is both unsustainable for the planet and an amount of animal protein never consumed by our ancestors.
Excess meat consumption has its health risks, and summer is a great time to dial down the meat and eat way more beans, green veggies, fruits, nuts, and seeds.
The following reasons for consuming less meat may help you make the decision to eat a summer plant-based diet with only 10% animal protein.
7 Reasons to Eat Less Meat
- In 2012, the Harvard School of Public Health evaluated over 120,000 meat eaters. After 28 years, those who ate the most meat (two servings a day) had a 30% increased risk of dying compared to those who did not eat red meat.
- In a 2010 study published in the journal Circulation, 84,000 nurses were evaluated for 26 years. Those who ate three servings of meat per day had a 29% increased risk of chronic heart issues compared to those who ate only half a serving per day.
- Red meat is high in an amino acid called carnitine. When carnitine is digested by gut microbes, they produce a toxic byproduct called trimethylamine-N-oxide or TMAO. In a 2013 study published in the New England Journal of Medicine, 4,000 otherwise healthy patients who had the highest levels of TMAO had a 50% increased risk of a cardiovascular event over the next three years.
- In 2011, the American Institute for Cancer Research suggested reducing consumption of cooked red meat to less than 18 ounces per week and avoiding processed or packaged meats to reduce cancer risk.10
- A 2012 study in the journal Stroke followed 125,000 people over 22 years. For every one to two ounces of processed meat eaten per day, there was a 30% increased risk of a stroke.
- In a 2011 study in the American Journal of Clinical Nutrition, Harvard researchers followed more than 200,000 men and women for 28 years. For every two ounces of processed meat eaten per day, there was a 32% increased risk of type 2 diabetes.
- It takes 7-8 pounds of feed to produce just one pound of beef. It takes 1,000 tons of water to make just one ton of grain, and the vast majority of grain is produced to feed beef and pork. As our population grows, this way of eating is simply not sustainable.
What is now known from the ancient wisdom of seasonal eating is that circadian rhythms of nature change microbes in the soil, on the foods we eat, and in our guts.
These microbes regulate the diurnal and nocturnal functions of the body. Ayurveda hacked into and downloaded the intelligence of these rhythms thousands of years ago, and you can too!
Sign up for our free 3-Season Diet Challenge to find out more each month about what and how you should be eating.