If you think a vegan diet automatically equals a healthy diet, think again!
True it can be packed with veggies, but if you’ve ever met the vegan with a Diet Coke in one hand and a chocolate brownie (sans the eggs and butter, of course) in the other, you know it can be a thoroughly unhealthy diet.
A vegan diet, by definition, excludes all animal products. No animal flesh. No milk from cows, goats, sheep or other mammals. No eggs. Not even honey. What’s left can vary tremendously from one vegan to the next.
Often people do choose to adhere to a vegan diet for health reasons, but others want to eat lower on the food chain out of respect for animals or to minimize their carbon footprint and help protect the environment.(1)
But is vegan actually healthy?
Thanks to the Seventh Day Adventists and the epidemiologists who studied them, we now have compelling evidence that a vegan diet can be healthier than one that includes meat and fish. Many Seventh Day Adventists follow their church’s doctrine that recommends a vegetarian diet. The researchers found that, compared to non-vegetarians, vegetarians (including vegans and lacto-ovo vegetarians) were much less likely to get colon cancer or prostate cancer, or to die from cardiovascular disease or breast cancer.
Among men, lacto-ovo vegetarians (they eat dairy and eggs) were 15% less likely to die from any cause compared with non-vegetarians, and there seemed to be some added benefit to being vegan, as this group was 18% less likely to die from any cause versus the non-vegetarians.(2)
Other studies have looked at the gut microbiota (ie, the bacteria in our stool) in people with different diets and have found that the microbiome in those who eat meat differs from vegetarians, and further differs from that in vegans. Research indicates that the vegan gut has fewer inflammatory bacteria, and more species that protect against inflammation, obesity and type 2 diabetes.(3)
A number of smaller studies reveal additional benefits of the vegan diet, such as one where sedentary people on a raw vegan diet appear to be as heart healthy as the non-vegetarian endurance runners(4). Another research study found that a vegan diet along with support groups and lifestyle changes helped men with prostate cancer control the disease.(5)
But there is such variety in the vegan diets studied and associated interventions that it is hard to make generalizations.
Why the vegan diet may be healthier:
There are strong theoretical reasons to think that there is value in consuming a vegan diet.
1) Today most of our available meat and poultry, due to being grain-fed, are laden with pro-inflammatory fats.
For example, the ratio of omega-6:omega-3 fatty acids is ideally no higher than 4:1, but a review article found that, on average, the ratio was 7.65:1 for grain-fed beef and 1.53:1 for grass-fed beef.(6) A study of chickens fed cereal-based feed also had lower omega-3 fatty acid levels compared with the birds given access to pasture.(7)
2) Meat and poultry are inherently highly acidic, more so than plant-based proteins, because they have a higher concentration of the sulphur containing amino acids that become acidic when metabolized.
Diets high in animal protein have been associated with numerous chronic diseases, such as cardiovascular disease, hypertension, type 2 diabetes, and possibly osteoporosis, cancer and overall mortality.(8-12)
3) Environmental toxins, such as dioxin and PCBs, both fairly ubiquitous industrial pollutants, are concentrated in animal fat when the animals eat contaminated plant foods and soil.
Ninety percent of human ingestion of dioxins occurs through animal food. These contaminants increase risk for cancer and developmental, immunologic, and endocrine toxicity.(13) Mercury, another toxin prevalent in our oceans, accumulates in many fish, and can be harmful to our nervous, digestive and immune systems, lungs and kidneys.(14)
Plant vs Animal: How to get the necessary protein and nutrients as a vegan
One benefit of animal protein is that unlike plant-based protein, animal protein is a “complete protein,” meaning you get adequate amounts of all the essential amino acids your body cannot make on its own when you eat it.
Vegans have to work harder to consume adequate amounts of complete protein because plant-based proteins are almost all low in one to three essential amino acids. However, any combination of two types of vegan protein in a day (eg, legumes and seeds, or legumes and whole grains, or nuts and seeds, or whole grains and nuts) provides the necessary combination of essential amino acids.(15)
One pitfall to look out for is vegan protein powders. Most powders are not optimized with branch-chain amino acids, and therefore are not highly bioavailable and not a great source of protein. This is why Parsley Health’s professional-grade pea-and-rice based Rebuild protein powder is superior to most powders – it has been optimized with the addition of the amino acids like leucine required to make it a complete protein.
Another common argument for consuming animal products – particularly dairy – is calcium. However, on review of studies of dairy and bone strength, the totality of evidence does not point to dairy as necessary. Vegans can get plenty of calcium from their diet without supplements by consuming dark green vegetables and nuts or seeds daily.
Especially good foods are collard greens, kale, almonds and sunflower seeds. Not only that, but they don’t need as much calcium as meat-eaters. That’s because animal flesh is acidic, forcing calcium stored in the body (eg, in bones) to be drawn into the bloodstream to buffer the acid.
Essentials: B12, Iron, Vitamin D and Omega-3s
There are a few nutrients that you do need to pay attention to if you want to try a vegan diet safely.
The first one is vitamin B12. Unless you are eating some really buggy lettuce (which one might argue would make you less than vegan), there is no way to get sufficient B12 as a vegan and it is important to take a supplement, such as our vegan Rebuild protein powder which contains a complete multivitamin.
Iron is also worth consideration, in particular for menstruating women. Although there are many plant-based sources of iron, it is harder for the body to absorb vegan-sources of iron than animal-based sources, so supplementation might be needed.
Next, Omega-3 fatty acids are abundant in certain plant-based foods, like flax, walnuts, chia and hemp seeds. However, our bodies are only able to convert small amounts of plant-based omega-3s into the most beneficial forms our bodies need – DHA and EPA. In comparison, it is much easier to absorb DHA and EPA directly from fish and pasture-raised eggs and meat.
Finally, there is almost no vitamin D in a vegan diet, and most of us (vegan or not) are Vitamin D deficient as we don’t get a lot of sun exposure. The better supplemental form of vitamin D is D3, rather than D2. Though D3 frequently comes from animal sources (eg, lanolin from sheep’s wool or fish oil) there is a plant-derived D3 from lichen.We recommend routine testing for all vegans and vegetarians to ensure they are getting adequate nutritional support.
On countless occasions I have identified B12, iron and Vitamin D deficiency in my vegan patients which we were easily able to correct with the right supplements, allowing them to safely stay with their vegan diet.
How a vegan diet can help depression and heart disease
Diets impact more than our bodies, they can impact our mental health powerfully. For example, I had a 52-year-old patient who started a vegan diet high in veggies and without refined grains or sugar. As a result, her bipolar disorder was the best controlled it had ever been, allowing her to finally feel well, mentally and physically, on her medication.
I had another 62-year-old patient who had a cardiac stent placed for a clogged artery and chest pain. Despite the stent and no evidence of any more clogged vessels, the chest pain persisted, but a few months after he started a vegan diet, his chest pain resolved. Dean Ornish, MD, did pioneer work in this area, showing that a vegetarian diet (low-fat, no sugar in this study), along with exercise, stress management, and psychosocial support could successfully reduce angina symptoms and reverse the accumulation of plaque in people’s arteries.(16)
In her book, Radical Remission, Kelly Turner, PhD, wrote about people with cancer who used only alternative means to recover from cancer, and for some, this involved adhering to a plant-based diet high in vegetables and no sugar, meat, dairy and refined foods.(17)
Who is the vegan diet right for?
People are unique in terms of what makes them feel well and their comfort with different dietary plans. If you are interested in seeing what effect a vegan diet has on you, do it with the guidance of someone who has experience finding vegan foods that are healthy, satisfying and filled with a sufficient variety of nutrients.
Notice how you feel after 3 weeks on it. Check immune markers such as your white blood cell count and high sensitivity c-reactive protein, as well as cholesterol, to see what impact it has on these markers – for some people the positive effects are astounding.
The ideal vegan diet consists of whole foods, lots of vegetables, and nearly zero refined grains and sweets. If you want to try it, just be sure to plan ahead before making this transition, so you don’t end up reaching for that vegan chocolate brownie instead of a handful of walnuts when you’re hankering for a snack, and keep in mind which nutrients you might need to supplement.
If done this way it can potentially decrease your risk for chronic diseases, such as heart disease and some cancers.
Need to get started with a few delicious vegan recipes? Start your day off by making our Pumpkin Pie Smoothie, check out our Simple Plant-Powered Meals for lunch and dinner ideas or whip up a batch of our Peanut Butter Energy Balls for the perfect snack!
Final thoughts on the vegan diet
- Eat plentifully from the rainbow of veggies, including lots of leafy greens.
- Limit refined sugars, simple carbs and grains.
- Pay attention to your protein intake – make sure you eat a variety of foods higher protein on a daily basis (eg, beans and seeds).
- Supplement with B12 and find out if you also need to supplement iron, vitamin D, and omega-3 fatty acids.
- Scarborough P, et al, Dietary greenhouse gas emissions of meat-eaters, fish-eaters, vegetarians and vegans in the UK. Climatic Change, 2014; July, 125(2):179–192.
- Tai Le L and Sabaté J, Beyond Meatless, the Health Effects of Vegan Diets: Findings from the Adventist. Cohorts Nutrients. 2014, June: 6(6):2131-2147.
- Glick-Bauer M and Yeh MC, The Health Advantage of a Vegan Diet: Exploring the Gut Microbiota Connection. Nutrients. 2014, Nov; 6(11): 4822–4838.
- Fontana L, et al, Long-term low-calorie low-protein vegan diet and endurance exercise are associated with low cardiometabolic risk. Rejuvenation Res, 2007, June; 10(2):224-34.
- Ornish D, et al. Intensive lifestyle changes may affect the progression of prostate cancer. J Urol. 2005 Sep; 174(3): 1065-9.
- Daily CA, et al, A review of fatty acid profiles and antioxidant content in grass-fed and grain-fed beef. Nutr J. 2010 Mar; 9(10).
- Ponte PI, et al, Restricting the intake of a cereal-based feed in free-range-pastured poultry: effects on performance and meat quality. Poult Sci. 2008 Oct: 87(10):2032-42.
- Anand SS, et al. Food Consumption and its Impact on Cardiovascular Disease: Importance of Solutions Focused on the Globalized Food System: A Report From the Workshop Convened by the World Heart Federation. J Am Coll Cardiol. 2015 Oct 6; 66(14):1590-1614.
- Altorf-van der Kuil W, et al. Dietary protein and blood pressure: a systematic review. PLoS One. 2010 Aug 11;5(8).
- Viguiliouk E, et al, Effect of Replacing Animal Protein with Plant Protein on Glycemic Control in Diabetes: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Nutrients. 2015 Dec 1;7(12):9804-24.
- Campbell TC, The China Study, Benbella Books Inc, 2006.
- Song M, et al, Association of Animal and Plant Protein Intake With All-Cause and Cause-Specific Mortality. JAMA Intern Med. 2016 Oct 1;176(10):1453-1463.
- “Dioxins in the food chain: Background” https://www.aphis.usda.gov/animal_health/emergingissues/downloads/dioxins.pdf
- “Mercury and health” http://www.who.int/mediacentre/factsheets/fs361/en/
- Mahan K & Escott-Stump Sylvia, Krause’s Food, Nutrition, & Diet Therapy, 11th Ed, Saunders, 2004.
- Ornish, D, et al, Intensive Lifestyle Changes for Reversal of Coronary Heart Disease. JAMA. 1998;280(23):2001-2007.
- Turner KA, Radical Remission, HarperOne, 2014.