Are We What We Eat? The Moral Imperative of the Medical Profession to Promote Plant-Based Nutrition
Section snippets
“We Evolved to Eat Meat, and It Is Only Natural”
Heavy consumption of meat is often defended in an evolutionary context as part of the trendy “Paleolithic” diet. However, the premise that Paleolithic humans survived mostly on wild animal products is flawed.1 The diets of Paleolithic humans were often predominantly plant-based—containing starchy vegetables and even cooked whole grains2 —and provided an estimated 70 to 150 g of fiber per day.3 Additionally, the hunter-gatherer lifestyle required significant physical effort to obtain food;
“We Need To Eat Meat to be Healthy”
There is a widespread misconception that meat consumption is necessary for adequate protein intake. However, the Institute of Medicine recommends 0.8 g of protein per kg of body weight per day, which can be easily obtained through eating a variety of protein-rich plant-based foods including soy, legumes, nuts, and seeds.12 Although a strict vegan diet (without adequate planning) may be more susceptible to deficiencies in iron, calcium, and omega-3 fatty acids, a well-balanced plant-based diet
“Nutritional Choices Are Purely a Matter of Personal Preference, as They Do Not Affect Other People”
Nutritional patterns have substantial impacts on the health and welfare of others on a local and global level. Meat consumption, and beef eating in particular, confers a significant carbon footprint through land use and deforestation, water consumption, and methane emissions. Food systems account for a third of the global greenhouse gas emissions that are attributable to human activity, and animal-based foods are responsible for double the emissions of plant-based foods.71,72 Compared with the
Implementation Barriers and Strategies
In addition to current financial incentives that maintain the nutritional status quo by prioritizing profitability above all else, we propose several cognitive barriers that may hinder progress toward healthier and more ethically sustainable food systems (Table 1). Although education and reframing are important for all individuals, they are particularly critical for physicians who are seeking to counsel patients effectively. Although it is vanishingly rare to see a physician smoke, it is common
Author Contributions
Sarah C. Hull was responsible for the conception and primary drafting of this manuscript. Justin Charles and Arthur L. Caplan contributed substantial additional content through extensive revisions.
Disclosures
Drs. Hull and Caplan have no conflicts of interest to declare. Dr. Charles serves as an (unpaid) volunteer medical consultant for ActualFood, a philanthropically funded technology lab dedicated to helping individuals adopt a whole-food, plant-based diet to improve chronic disease outcomes. His role as consultant is to advise on program development strategies and help make connections to other researchers and experts in the field of plant-based nutrition.
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2023, Animal Frontiers
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