I discuss nutrition a lot on this blog, and two themes I come back to over and over again are the importance of avoiding processed foods and the benefits of increasing protein. I’ve also stated in the past that I am diet agnostic, by which I mean I believe a multitude of diets can work and the most important thing is to find the diet that works for you. With that said, patients and readers of this blog may have picked up on the fact that I tend to be partial to low-carb diets. This is not because I believe that low-carb diets are the only way to lose weight or that they are always the best choice, but because in my years of practice I’ve found many patients to have an easier time sticking to these plans and therefore achieving results than they do with other types of diets.
Where do plant based/vegan diets fall into my thinking?
Let me state at the outset that I have had a few patients over the years (and have some currently) who have done VERY well on a plant-based diet, so there is no question that this eating pattern can work well. There are also some studies that show vegans and vegetarians are, on average, a bit healthier and longer-lived than the average person. So I am more than happy to work with patients who prefer a plant-based lifestyle. If you put a gun to my head and ask me if going vegan is a good way to become healthier and I could only give a yes/no answer, I would unequivocally answer “yes.” But as with everything in medicine, there are some nuances that are worth discussing.
First, let me make a key point that as veganism has become more popular, food companies have responded by bringing more and more processed vegan foods to the market. It is now easily possible to be a vegan and live on vegan “burgers,” vegan “pizza”, vegan “cheese,” vegan chips, vegan cookies, and other highly processed junk foods that are entirely plant-based. There is no reason to think that this would be a healthy eating pattern, and I would strongly suspect that a person who ate this way would be worse off than a person who followed a “clean” omnivorous diet such as the Paleo eating plan, which includes a lot of meat, but eliminates all processed and refined foods. This can’t be stressed enough: being vegan can be extremely healthy, or it can be unhealthy. It depends on the type of vegan that you are. Simply avoiding animal-based foods is not a guarantee of health.
The big proponents of veganism (think of folks like Drs. Michael Greger, Caldwell Esselstyn, or T. Colin Campbell) specifically advocate a ‘Whole Foods Plant Based” eating approach, meaning a diet of unrefined plant foods such as intact whole grains, beans, nuts, fruits, and vegetables. This is the type of veganism that has been shown to have positive effects on health, and it shouldn’t be too surprising as to why. This way of eating simultaneously limits processed/refined foods, increases fiber intake, and increases the intake of healthful plant compounds such as vitamins, polyphenols, and phytochemicals, which have all been associated with lower risks for cancer, heart disease, and other serious chronic diseases.
Proponents of veganism sometimes have an almost religious quality when discussing their diet. (To be fair, so do proponents of many other diets, such as Paleo or Keto). They frequently argue that plant-based diets are unambiguously the only diets that can lead to optimal health and that science is on their side. This is just not true. Epidemiological studies do suggest benefits to being plant based, but epidemiological studies are notoriously unreliable and prone to bias. Moreover, when scientists control for some of these biases (for example, trying to sort out the meat eaters who frequent McDonald’s versus those who eat organic salads with grass-fed steak) the benefits of being vegan largely evaporate. In other words, the biggest benefits to veganism seem to come from eating a high-quality whole-foods diet, rather than from whether that diet incorporates animal products or not. As for randomized controlled studies, which are generally more reliable, many of these have shown a benefit to being whole-foods plant-based, but these are usually in comparison to a person eating a standard western diet which (again) is high not only in animal products, but also in refined carbohydrates, sugars, and added oils. To my knowledge, nobody has done a good study comparing a whole-foods plant-based diet to a high quality whole-foods omnivorous diet. So while it’s virtually certain that adopting a whole-foods plant-based diet is a massive improvement over following a standard American diet, the jury is very much out on whether or not it is substantially better than following a high-quality diet that does incorporate animal products.
Secondly, a word on protein. Muscle scientists have studied this question extensively, and there is no question that people can get adequate protein and build strong, lean, healthy muscles on a plant-based diet. Therefore, the idea that vegans can’t get adequate protein is simply a “bro science” myth. However, just because vegans CAN get adequate protein doesn’t mean that they ARE getting adequate protein. Foods like beef, chicken, eggs, and yogurt are much higher in protein than foods like legumes and whole grains, and most people who are eating a decent meat based diet will have a simpler path toward meeting their protein needs than a vegan.
Therefore, while it is absolutely possible to get enough protein on a vegan diet, it does require a bit more conscious attention than it does of the omnivore, and if you are vegan, it really behooves you to track your protein intake for awhile to get a sense of whether you are meeting your goals or not. When I meet a plant-based patient, this is one of the first things I try to hone in on, as many vegans are overestimating how much protein is in their beans and nuts, and falling way short of the daily protein required to build and maintain healthy levels of muscle mass.
Third of all, from personal experience I have found that there is a wide range of responses to various diets. I’ve known patients who have adopted a keto diet and seen their cholesterol go way down, and others who have seen it skyrocket. I’ve known patients who adopted a plant-based diet and loved it and felt great, and others who found it to give them bloating, fatigue, and sluggishness. There’s simply no substitute for trying out different things and seeing what works for you.
Finally, let me state that there may be reasons to eat a plant-based diet that have nothing to do with personal health. Concerns about the environment, animal welfare, and ethics are all valid, and I would never attempt to talk somebody who is motivated by these issues out of a dietary pattern that they feel is having s beneficial impact on society as a whole. However, as a medical doctor, my concern (and area of expertise) is with the health of my patients, so I am intentionally limiting my discussion of this topic to the health effects.
Taken in sum, being vegan can be a terrific way to improve your health and feel great, but I don’t believe it is the only way to do so. If you are vegan and thriving (or wish to give it a try), by all means continue to follow your diet. Just make sure to pay extra attention to your protein intake and to limit your intake of highly processed vegan “junk” foods. If being vegan doesn’t work for or interest you, rest assured that there are other valid paths to better health.