Becoming More Plant-Centric: A Review of Plant-Based Diets

Author: Christian Maino Vieytes, Masters Candidate, University of Illinois

Dr. Ellsworth Wareham lives a comfortable and simple life as a retired cardiothoracic surgeon. He left medical practice 40 years ago when he was 74 years of age. That makes him a fruitful and thriving 104-year-old, today! The question on everyone’s mind, I would imagine, is: how does he do it? How did Dr. Wareham achieve centenarian status? Well, prodding Dr. Wareham with the relevant question prompts a simple response: he attributes his longevity to the adoption of a whole-foods plant based diet over 50 years ago, a common practice within his religious community of the Seventh-Day Adventists. But Dr. Wareham is probably just a genetic outlier, right? Well, let’s take a look at what the science has to say about plant-based diets before we cast judgment.

Definition

We’ve heard the term, perhaps, thrown around loosely, but what does it actually mean to follow a plant-based diet? Researchers at Harvard have established that a plant-based diet “emphasizes intake of whole grains, fruits, vegetables, nuts and legumes” and consists “of a diverse family of dietary patterns, defined in terms of low frequency of consumption of animal foods.” Some describe the diet as completely abstaining from all animal products; an exclusively plant-based diet. The popular Mediterranean Diet, with its focus on these food groups and the minimization of animal products, would certainly fit the definition. Plant-based diets distinguish themselves from vegan diets, which also define themselves by the elimination of all animal products, in that vegans do not necessarily get the majority of their calories from whole plant foods. You can be vegan and eat as many fries (fried in oil) and Oreos as you please but it does not mean it’s healthy!

Cancer

Much of the beneficial effects of consuming a primarily or exclusively plant-based diet arise from the ratio of fruits/vegetables to products of animal origin. With respect to cancer, several studies have demonstrated that this ratio is highly relevant to one’s risk of developing the disease. Studies on the Mediterranean diet have also established that variations of the diet that maximize fruit and vegetable consumption while minimizing meat and other animal products are associated with a reduced risk of various types of cancer. Specifically, various chemicals found in plants have been found to have protective effects while chemicals that arise in meat and also through the cooking process are responsible for mutations in our DNA that can lead to cancer.

Cardiovascular Disease and Diabetes

Much of the benefits of a plant-based diet come from the large amounts of antioxidants, fiber, and whole grains that people on this diet consume relative to the rest of the population. Average fiber intake in the United States for adults is 17 g/day, which is nowhere close to the recommended intake level of ~30 g per day. Those on a plant-based diet may easily consume upwards of 60-80 g per day. Eating primarily high-fiber, whole-plant foods has been shown to effectively promote healthy weight loss by increasing feelings of fullness and lowering the total intake of calories, since fiber has no digestible calories. Fiber is also known for its cholesterol-lowering effects in the blood and its ability to regulate blood-sugar levels. Put all together, these effects provide the basis for why plant-based diets are so effective in treating cardiovascular disease and type 2 diabetes. Patients can work with their physicians or dietitians to develop a plan that promotes this pattern of eating.

A Sustainable Alternative

Aside from the health benefits associated with eating an exclusively plant-based diet, there are also substantial environmental benefits that the planet can profit from by incorporating more fruits and vegetables on our plate. Did you know it requires 2,500 gallons of water to produce one pound of beef? Not only does livestock agriculture guzzle astronomical amounts of this limited resource but the United Nations recognizes it as a leading contributor of greenhouse gas emissions, water contamination, and species extinction.

Who knew we could both benefit our bodies and the planet by filling our plate with more fruits and vegetables?

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