Many People are Eating Too Much Protein

A high intake of protein is common in western societies and is often promoted as part of a healthy lifestyle. Protein is composed of amino acids and when too much protein is consumed, too much amino acid, such as leucine, becomes present in the body. Amino-acid (leucine)-mediated mammalian target of rapamycin (mTOR) signaling in macrophages has been found to be involved in the pathogenesis of ischemic cardiovascular disease. Another amino acid, isoleucine, when consumed at high levels promotes heart disease through modification of lipid profiles.

There’s a misconception that plant proteins are not as complete a source of amino acids as animal proteins. While those eating a diet rich in animal meats and dairy often consume unhealthy amounts of proteins, plant proteins have a lower essential amino acid content than do animal meats, and a healthy whole food plant-based diet provides sufficient and complete protein. Plants contain a healthy amount of protein, not too much. Some plant foods contain all the 9 essential amino acids in ratios and amounts that are less damaging to your overall health that, for example decreases mortality, improves bone mass, when compared to animal proteins. These include: hemp seeds, quinoa, soy, pea, brown rice and pumpkin. On my other blog about skincare, I’ve posted a summary of the many benefits of soy.

Consider the recent data about the amino acid, isoleucine. Prof. Dr. Dudley W. Lamming, Ph.D. at the Univ of Wisconsin, and team, have found that high levels of isoleucine is associated with ill health. In their study, mice eating less of this specific amino acid, overrepresented in diet of obese people, live longer and healthier.  Previous studies by the group found that people with higher body mass index measurements (i.e., people that are more overweight or obese) tend to consume more isoleucine, an essential amino acid everyone needs to consume. Isoleucine is plentiful in foods including eggs, dairy, soy protein and many kinds of meat. So, imagine a diet that many in the US follow, where eggs and dairy are consumed in the morning, and meat throughout the day. – too much isoleucine. Now consider a vegan diet where where vegetables are eaten along with moderate amounts of soy – just enough isoleucine is consumed.

There is no longevity zone, such as here in Southern California’s Loma Linda Blue Zone, in the world where people live longer by eating lots of meat or animal protein. Longevity zones, also called “Blue Zones,” are areas where people live substantially longer and healthier. What all Blue Zones have in common is that people consume few animal products, whether it is land animals or sea animals. For example, long-lived people in Okinawa (Japan), Sardinia (Italy), Icaria (Greece), or the Seventh-Day Adventists in California consume little or no meat. There are other factors why people live longer in these zones, including exercise (walking) and contributing to the greater good of their society, but a low animal protein intake is a clear commonality in their superior health. People, such as those in the hills of Sicily, who reach a very old age, often to 100 years, do not consume high amounts of protein. They reach old age without eating lots of meat or without following a paleo diet, taking dietary supplements such as protein powder, or drinking whey shakes. and they certainly don’t listen to David Sinclair’s gobbledygook about supplements. As scientists and physicians at Harvard’s School of Public Health have reported, “Replacing animal protein of various origins with plant protein was associated with lower mortality.”

As detailed in my 2020 book, Thinking and Eating for Two, too much protein, especially animal protein, activates mTOR biochemical pathways in the human body leading to a number of negative consequences, including cardiovascular disease and cancer.

So here’s what we should be eating. Follow the diets in the Blue Zones, which are typically rich in the following:

• Vegetables: They’re a great source of fiber and many different vitamins and minerals. Eating more than five servings of fruits and vegetables a day can significantly reduce your risk of heart disease, cancer and death.
• Legumes: Legumes include beans, peas, lentils and chickpeas, and they are all rich in fiber and protein. A number of studies have shown that eating legumes is associated with lower mortality (1, 2, 3).
• Whole grains: Whole grains are also rich in fiber. A high intake of whole grains can reduce blood pressure and is associated with reduced colorectal cancer and death from heart disease (1, 2, 3).
• Nuts: Nuts are great sources of fiber, protein and polyunsaturated and monounsaturated fats. Combined with a healthy diet, they’re associated with reduced mortality and may even help reverse metabolic syndrome (1, 2, 3).

Reduce your protein intake to reduce mTOR and you’ll likely live longer, given that “mTOR has been implicated in many of the processes that are associated with aging.” You’ll feel better too, including having less inflammation in your joints.