What are the pros and cons of plant-based eating?
The Negative Effects and Benefits of Plant-Based Diets
Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.
Intro: In this video, I look at some overall stats on the benefits and potential risks of eating a plant-based diet. It’s a great introductory video if you’re just getting started or want to share with friends and family. Check it out.
Vegetarian diets and lifestyle have been shown to reduce the risk of many chronic diseases, which now account for the major global burden of diseases. But the actual direct medical costs had never been quantified before. Here’s what they found. The same amount spent on dental work, but compared to meat-eaters who similarly don’t smoke or drink, or compared to the general population, vegetarians had significantly lower inpatient, outpatient, and total medical––suggesting more plant-based eating could be an effective strategy to save on healthcare costs.
Here’s how it broke down. Significantly lower costs for chronic lifestyle conditions, such as high blood pressure and high cholesterol. This makes sense. Those eating plant-based diets centered around whole plant foods nailed the targets for cholesterol, triglycerides, and systolic and diastolic blood pressure 93 percent of the time, 97 percent of the time, 88 percent of the time, and 95 percent of the time, respectively.
Nearly a 50 percent drop in medical costs due to depression too. That’s interesting, as well as lower costs across the board.
Cerebrovascular disease is another name for stroke. Wasn’t there that study that showed vegetarians had higher stroke risk? True, but that was before two subsequent studies found a lower risk of stroke with a vegetarian diet, and not just by a little. For ischemic stroke, the most common clotting type of stroke, vegetarians consistently had about 60 percent lower risk. And for bleeding strokes, about 65 percent lower risk than nonvegetarians. And this was despite higher homocysteine due to lower vitamin B12 intake, which is what may have led to higher stroke risk in the previous study.
Overall, if you do a systematic review of all the major studies, a comprehensive meta-analysis found a significant protective effect of a vegetarian diet versus the incidence and/or mortality from ischemic heart disease and incidence from total cancer, with a vegan diet conferring about twice the reduced risk cancer-wise.
You can also look at it the other way. What if you decide to stop eating vegetarian and start eating meat? The Adventist Health Study looked at that, and found that compared to those who stayed vegetarian, those who started eating meat suffered a 231 percent increased risk of gaining weight, 166 percent increased risk of developing diabetes, 152 percent increased risk of having a stroke, and 146 percent increased risk of being diagnosed with heart disease. And if you keep eating meat, you may cut your lifespan by three and a half years. So, better to not just to cut out meat, but cut it out for good.
But it’s not all-or-nothing. Even just cutting down may help. A food pattern that emphasizes plant-derived foods was found to be associated with a reduced risk of all-cause mortality, meaning living a significantly longer life. Here are the cumulative hazards of death across categories of pro-vegetarian eating, meaning the closer you eat towards a completely plant-based diet, the lower your risk of death falls. The researchers conclude that there is now evidence that the simple advice to increase the consumption of plant-derived foods with reduction in the consumption of foods from animal sources confers a survival advantage.
So, there are multiple benefits even eating the direction of a more plant-based diet. But what about any risks? Despite concern for protein deficiency, adequate amounts of protein, which means 0.8 g/kg body weight, which is about 50 grams a day, can be consumed in a solely plant-based diet, as seen among the other billion plus people around the world who don’t eat meat. Vitamin B12 deficiency, on the other hand, is a very real concern without a regular reliable source, and I have videos on how to do that, either through supplements or fortified foods.
One benefit you don’t hear much about is the role our diets play in the emergence of pandemic infectious diseases, the subject of one of my recent books. It doesn’t take much for a virus to jump from one animal to another, but there are no examples of plant viruses ever jumping to humans for the same reason we don’t ever come down with a really bad case of Dutch elm disease.
The largest and oldest association of nutrition professionals in the world is clear: Plant-based diets are appropriate for all stages of the life cycle and may actually provide health benefits for the prevention and treatment of certain diseases. For example, vegetarians and vegans are at reduced risk of ischemic heart disease, type 2 diabetes, high blood pressure, certain types of cancers, and obesity. And to learn more, they encourage people to go check out a few good websites.
As the emeritus dean of the School of Public Health at Loma Linda once said at a nutrition conference: “Attitudes toward vegetarian diets have progressed from ridicule and skepticism to condescending tolerance, to gradual and sometimes grudging acceptance, and finally to acclaim.”
Please consider volunteering to help out on the site.
- Lin CL, Wang JH, Chang CC, Chiu THT, Lin MN. Vegetarian Diets and Medical Expenditure in Taiwan-A Matched Cohort Study. Nutrients. 2019;11(11):2688.
- Jakše B, Jakše B, Pinter S, et al. Dietary Intakes and Cardiovascular Health of Healthy Adults in Short-, Medium-, and Long-Term Whole-Food Plant-Based Lifestyle Program. Nutrients. 2019;12(1):55.
- Spence JD, Tangney C. Lower risk of stroke with a vegetarian diet. Neurology. 2020;94(11):463-464.
- Chiu THT, Chang HR, Wang LY, Chang CC, Lin MN, Lin CL. Vegetarian diet and incidence of total, ischemic, and hemorrhagic stroke in 2 cohorts in Taiwan. Neurology. 2020;94(11):e1112-e1121.
- Dinu M, Abbate R, Gensini GF, Casini A, Sofi F. Vegetarian, vegan diets and multiple health outcomes: A systematic review with meta-analysis of observational studies. Crit Rev Food Sci Nutr. 2017;57(17):3640-3649.
- Singh PN, Arthur KN, Orlich MJ, et al. Global epidemiology of obesity, vegetarian dietary patterns, and noncommunicable disease in Asian Indians. Am J Clin Nutr. 2014;100 Suppl 1(1):359S-64S.
- Martínez-González MA, Sánchez-Tainta A, Corella D, et al. A provegetarian food pattern and reduction in total mortality in the Prevención con Dieta Mediterránea (PREDIMED) study [published correction appears in Am J Clin Nutr. 2014 Dec;100(6):1605]. Am J Clin Nutr. 2014;100 Suppl 1:320S-8S.
- Rocha JP, Laster J, Parag B, Shah NU. Multiple Health Benefits and Minimal Risks Associated with Vegetarian Diets. Curr Nutr Rep. 2019;8(4):374-381.
- Reddy BL, Saier MHJ. The Causal Relationship between Eating Animals and Viral Epidemics. Microb Physiol. 2020;30(1-6):2-8.
- Melina V, Craig W, Levin S. Position of the Academy of Nutrition and Dietetics: Vegetarian Diets. J Acad Nutr Diet. 2016;116(12):1970-1980.
- Hardinge MG, Johnston PK. Recognition. Am J Clin Nutr. 1999;70(3 Suppl):431S-2S.
Motion graphics by Avo Media
Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.
Intro: In this video, I look at some overall stats on the benefits and potential risks of eating a plant-based diet. It’s a great introductory video if you’re just getting started or want to share with friends and family. Check it out.
Vegetarian diets and lifestyle have been shown to reduce the risk of many chronic diseases, which now account for the major global burden of diseases. But the actual direct medical costs had never been quantified before. Here’s what they found. The same amount spent on dental work, but compared to meat-eaters who similarly don’t smoke or drink, or compared to the general population, vegetarians had significantly lower inpatient, outpatient, and total medical––suggesting more plant-based eating could be an effective strategy to save on healthcare costs.
Here’s how it broke down. Significantly lower costs for chronic lifestyle conditions, such as high blood pressure and high cholesterol. This makes sense. Those eating plant-based diets centered around whole plant foods nailed the targets for cholesterol, triglycerides, and systolic and diastolic blood pressure 93 percent of the time, 97 percent of the time, 88 percent of the time, and 95 percent of the time, respectively.
Nearly a 50 percent drop in medical costs due to depression too. That’s interesting, as well as lower costs across the board.
Cerebrovascular disease is another name for stroke. Wasn’t there that study that showed vegetarians had higher stroke risk? True, but that was before two subsequent studies found a lower risk of stroke with a vegetarian diet, and not just by a little. For ischemic stroke, the most common clotting type of stroke, vegetarians consistently had about 60 percent lower risk. And for bleeding strokes, about 65 percent lower risk than nonvegetarians. And this was despite higher homocysteine due to lower vitamin B12 intake, which is what may have led to higher stroke risk in the previous study.
Overall, if you do a systematic review of all the major studies, a comprehensive meta-analysis found a significant protective effect of a vegetarian diet versus the incidence and/or mortality from ischemic heart disease and incidence from total cancer, with a vegan diet conferring about twice the reduced risk cancer-wise.
You can also look at it the other way. What if you decide to stop eating vegetarian and start eating meat? The Adventist Health Study looked at that, and found that compared to those who stayed vegetarian, those who started eating meat suffered a 231 percent increased risk of gaining weight, 166 percent increased risk of developing diabetes, 152 percent increased risk of having a stroke, and 146 percent increased risk of being diagnosed with heart disease. And if you keep eating meat, you may cut your lifespan by three and a half years. So, better to not just to cut out meat, but cut it out for good.
But it’s not all-or-nothing. Even just cutting down may help. A food pattern that emphasizes plant-derived foods was found to be associated with a reduced risk of all-cause mortality, meaning living a significantly longer life. Here are the cumulative hazards of death across categories of pro-vegetarian eating, meaning the closer you eat towards a completely plant-based diet, the lower your risk of death falls. The researchers conclude that there is now evidence that the simple advice to increase the consumption of plant-derived foods with reduction in the consumption of foods from animal sources confers a survival advantage.
So, there are multiple benefits even eating the direction of a more plant-based diet. But what about any risks? Despite concern for protein deficiency, adequate amounts of protein, which means 0.8 g/kg body weight, which is about 50 grams a day, can be consumed in a solely plant-based diet, as seen among the other billion plus people around the world who don’t eat meat. Vitamin B12 deficiency, on the other hand, is a very real concern without a regular reliable source, and I have videos on how to do that, either through supplements or fortified foods.
One benefit you don’t hear much about is the role our diets play in the emergence of pandemic infectious diseases, the subject of one of my recent books. It doesn’t take much for a virus to jump from one animal to another, but there are no examples of plant viruses ever jumping to humans for the same reason we don’t ever come down with a really bad case of Dutch elm disease.
The largest and oldest association of nutrition professionals in the world is clear: Plant-based diets are appropriate for all stages of the life cycle and may actually provide health benefits for the prevention and treatment of certain diseases. For example, vegetarians and vegans are at reduced risk of ischemic heart disease, type 2 diabetes, high blood pressure, certain types of cancers, and obesity. And to learn more, they encourage people to go check out a few good websites.
As the emeritus dean of the School of Public Health at Loma Linda once said at a nutrition conference: “Attitudes toward vegetarian diets have progressed from ridicule and skepticism to condescending tolerance, to gradual and sometimes grudging acceptance, and finally to acclaim.”
Please consider volunteering to help out on the site.
- Lin CL, Wang JH, Chang CC, Chiu THT, Lin MN. Vegetarian Diets and Medical Expenditure in Taiwan-A Matched Cohort Study. Nutrients. 2019;11(11):2688.
- Jakše B, Jakše B, Pinter S, et al. Dietary Intakes and Cardiovascular Health of Healthy Adults in Short-, Medium-, and Long-Term Whole-Food Plant-Based Lifestyle Program. Nutrients. 2019;12(1):55.
- Spence JD, Tangney C. Lower risk of stroke with a vegetarian diet. Neurology. 2020;94(11):463-464.
- Chiu THT, Chang HR, Wang LY, Chang CC, Lin MN, Lin CL. Vegetarian diet and incidence of total, ischemic, and hemorrhagic stroke in 2 cohorts in Taiwan. Neurology. 2020;94(11):e1112-e1121.
- Dinu M, Abbate R, Gensini GF, Casini A, Sofi F. Vegetarian, vegan diets and multiple health outcomes: A systematic review with meta-analysis of observational studies. Crit Rev Food Sci Nutr. 2017;57(17):3640-3649.
- Singh PN, Arthur KN, Orlich MJ, et al. Global epidemiology of obesity, vegetarian dietary patterns, and noncommunicable disease in Asian Indians. Am J Clin Nutr. 2014;100 Suppl 1(1):359S-64S.
- Martínez-González MA, Sánchez-Tainta A, Corella D, et al. A provegetarian food pattern and reduction in total mortality in the Prevención con Dieta Mediterránea (PREDIMED) study [published correction appears in Am J Clin Nutr. 2014 Dec;100(6):1605]. Am J Clin Nutr. 2014;100 Suppl 1:320S-8S.
- Rocha JP, Laster J, Parag B, Shah NU. Multiple Health Benefits and Minimal Risks Associated with Vegetarian Diets. Curr Nutr Rep. 2019;8(4):374-381.
- Reddy BL, Saier MHJ. The Causal Relationship between Eating Animals and Viral Epidemics. Microb Physiol. 2020;30(1-6):2-8.
- Melina V, Craig W, Levin S. Position of the Academy of Nutrition and Dietetics: Vegetarian Diets. J Acad Nutr Diet. 2016;116(12):1970-1980.
- Hardinge MG, Johnston PK. Recognition. Am J Clin Nutr. 1999;70(3 Suppl):431S-2S.
Motion graphics by Avo Media
Republishing "The Negative Effects and Benefits of Plant-Based Diets"
You may republish this material online or in print under our Creative Commons licence. You must attribute the article to NutritionFacts.org with a link back to our website in your republication.
If any changes are made to the original text or video, you must indicate, reasonably, what has changed about the article or video.
You may not use our material for commercial purposes.
You may not apply legal terms or technological measures that restrict others from doing anything permitted here.
If you have any questions, please Contact Us
The Negative Effects and Benefits of Plant-Based Diets
LicenseCreative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)
Content URLDoctor's Note
The B12 videos I suggest watching are The Optimal Vitamin B12 Dosage for Adults and The Healthiest Food Sources of Vitamin B12.
I talk about all of the nutrients to watch out for on my Optimal Nutrient Recommendations page.
I briefly mentioned my last non-cookbook book: How to Survive a Pandemic.
If you haven't yet, you can subscribe to our free newsletter. With your subscription, you'll also get notifications for just-released blogs and videos. Check out our information page about our translated resources.