Why blame the “oldest of foods” for the “newest of diseases”?
By: Dr. Pran Yoganathan, MD, Gastroenterology
The burden of chronic illnesses such as obesity and type 2 diabetes overwhelm me in my role as a gastroenterologist and hepatologist. The realities of the many subsequent metabolic complications that often appear alongside chronic illnesses makes treatment challenging.
One of the biggest health related challenges humanity will face in the years to come is reducing skeletal muscle loss due to age or chronic disease. Although there are a variety of factors influencing skeletal muscle loss, a key factor in addressing this challenge is the implementation of a balanced diet. This includes a key superfood - red meat.
Biology teaches us to study and understand organisms in the context of the environment they evolved in. Ideology aside, it is hard for science to ignore that we are simply the primate that learnt to hunt and value the nutrient density of meat. There is little doubt from an evolutionary perspective that humans were reliant on animal sourced foods prior to the advent of agrarian societies.
There is a concept known as the expensive tissue hypothesis which stipulates that for the human brain to have developed we needed a much more efficient gastrointestinal tract that relied on higher quality foods. Increased access to high quality food allows for ease of digestion and maximal nutrient delivery.
As humans evolved towards being hind gut fermenters of poor-quality plant material to mid-gut (auto enzyme) digesters, energy was freed up for the development of what is the most complex biological matter that exists on the planet and arguably in the universe - the human brain.
Where does that all take me? Meat was, and is, a critical part of the process of being human.
My question then is how did we end up in the situation where we blamed the oldest of foods for the newest of diseases?
Public health measures along with vaccinations and antibiotics help to ensure we no longer die of communicable disease (infection). Rather, we die of modern and chronic diseases brought on by lifestyle choices (non-communicable).
It is therefore not surprising that scientific literature contains numerous reports of associations between protein sources and markers of diet quality. This literature has led to the popularization of the protein package, an idea which has long blamed animal proteins for their contribution to an inadequate nutrient intake profile. Maybe this explains the association between meat protein and cardiovascular disease risk as well? Although these are important links between protein sources and diet quality, we must remember that the protein packages that have become readily available tend to be delivered in takeaway or ”junk” foods such as pizzas and burgers. These types of foods are protein, however they are often very low protein meals which are overwhelmed by refined carbohydrates and fats.
High-quality protein consumption optimizes protein metabolism at both the whole-body and skeletal-muscle level, especially in older people. Plant-based protein sources that are rich in fibre and micronutrients are valuable, but have lower anabolic potential than animal-based proteins. Strategies to improve plant protein properties include selective breeding, fortifying plant-based proteins with specific essential amino acids, mixing several plant proteins, as well as mixing plant and animal-based protein sources. We need high-quality food proteins to mitigate muscle loss.
When you compare fat and carbohydrates, protein is the macronutrient that makes the smallest observed contribution to energy intake and constitutes the lowest proportion of recommended intake. There are a limited number of foods offering large amounts of protein and most of these foods are consumed infrequently. This has resulted in an average protein consumption that ranges between 12% to 20% (of energy intake) in economically developed countries. These numbers are even less in underdeveloped countries.
Despite low protein consumption, media reports and research seem to implicate that animal sourced foods (often rich in protein) result in cardiovascular diseases and even cancer. Concerns regarding sustainability, planetary health, and the ethics of animal farming, alongside the growing vegan initiative have led to a situation where foods such as red meat have become linked to poor health and lack of environmental concern.
We have seen a rapid deterioration of global health at a trajectory that is impossible to fully comprehend. America has become synonymous with declining metabolic health. Has the consumption of animal sourced protein contributed to this downfall? A survey completed in 2003 and published in the American Journal of Clinical Nutrition revealed a surprising result about the protein intake of Americans.
Let’s assume 35% of the macros should come from protein for a relatively healthy and balanced diet:
The median intake of protein on a percentage of calories basis ranged from 13.4% in children aged 4 to 8 years to 16.0% in men aged 51 to 70 years.
Even the 95th percentile of protein intake did not approach the highest acceptable macronutrient distribution range of 35% for any specific age/sex group.
The highest 95th percentile of protein intake was 20.8% of calories in men aged 51 to 70 years.
The popular opinion is that Americans are big consumers of animal protein. But the truth is, people in America are protein starved.
Isn’t it interesting when you separate opinions from science?