Have you ever thought that we need to eat animal products to be healthy, because, after all, we were designed to eat them? It’s been on my mind for quite some time to write on this topic. But, wow is it controversial!

William C. Roberts, MD responded here to the question, “Are human beings herbivores, carnivores, or omnivores?” Dr. Roberts worked at the National Institute for Health (NIH) for 30 years, and currently is a cardiac pathologist at Baylor University Medical Center. He’s been the editor-in-chief of the American College of Cardiology for several decades. His response:

“Although most of us conduct our lives as omnivores, in that we eat flesh as well as vegetables and fruits, human beings have characteristics of herbivores, not carnivores (). The appendages of carnivores are claws; those of herbivores are hands or hooves. The teeth of carnivores are sharp; those of herbivores are mainly flat (for grinding). The intestinal tract of carnivores is short (3 times body length); that of herbivores, long (12 times body length). Body cooling of carnivores is done by panting; herbivores, by sweating. Carnivores drink fluids by lapping; herbivores, by sipping. Carnivores produce their own vitamin C, whereas herbivores obtain it from their diet. Thus, humans have characteristics of herbivores, not carnivores.”

Dr. Roberts also stated that atherosclerosis affects only herbivores, which caught my attention. “Dogs, cats, tigers, and lions can be saturated with fat and cholesterol, and atherosclerotic plaques do not develop (, ).”  Atherosclerosis is a disease in which plaque builds up inside our arteries, and can lead to serious problems, including heart attack and stroke. Indeed, cardiovascular disease is our second leading cause of death.

If we have characteristics of herbivores and not carnivores, it sheds light on the fundamental reason we achieve healthier outcomes when we eat more plants and fewer animal products. As physician and plant-based advocate Milton Mills puts it, it’s often the missing piece in the healthy-diet conversation.

If you haven’t yet seen the investigative documentary What the Health (available on Netflix and here), you may want to check it out and see why it has caused a stir. Dr. Mills is one of many interviewed in the film. Having earned his medical degree at Stanford, he’s an internist who practises in the Washington DC area. For years he’s been drawing attention to the ways we are anatomically and physiologically closer to herbivores than carnivores or omnivores. Check out some of his comparisons:

Even if doubt remains in our mind about whether humans can physically thrive for the long term while still eating both plant and animal products, it’s my perspective that our herbivorous characteristics help explain why the scientific evidence has shown that a diet high in saturated fat (found largely in animal products) and low in fibre (found exclusively in plants) simply spells trouble for our health.