by Jack Norris, RD
Vegan Diets—Health Benefits
A vegan diet can provide many health benefits. Vegans have:
- 3/4–1/2 lower rates of high blood pressure (1, 2)
- 2/3 lower risk of type-2 diabetes (3)
- 15–20% lower risk of cancer (4, 5)
- Significantly lower cholesterol levels (6)
Even though there are numerous benefits, in order to thrive, vegans should be aware of the nutrition issues below.
Calories, Protein, and Fat
It’s important to include some high-calorie, high-protein foods in order to feel satisfied.
Simply removing animal products from a typical American diet is going to leave you with mostly low-calorie foods such as salads, vegetables, and fruit. Eating only these foods could quickly leave you feeling hungry and weak, and thinking a vegan diet is a real challenge.
While severe protein deficiency is nothing to worry about, not eating some high-protein plant foods could leave you craving animal products or feeling fatigued—see Story from a Once-Failing, Now-Thriving Vegan.
Legumes—beans, peanuts, peas, lentils, and soy—seitan, and quinoa are the best sources of protein for vegans. Include a few servings of these foods each day—maybe even each meal.
People tend to think of animal products, and especially meat, as “protein,” but many are 50% fat. A very low-fat, plant-based diet might improve someone’s health in the short term, especially if they have high cholesterol, but it might not be ideal for longer periods. If you’re avoiding all added fats and you start to crave animal products, it might be time to increase the plant fats.
In fact, research has consistently shown that eating nuts—which are high in fat—improves markers for heart disease (7).
Although the research is still preliminary, it appears that some people don’t have the genetics to do well on a high carbohydrate diet (8). For such people, an eco-Atkins diet, high in plant proteins such as soy meats, legumes, and seitan, might be a better choice (9).
Finally, if you find yourself craving animal products, it could be because you have a strong preference for the taste of glutamate, also known as umami. Plant foods high in umami are ripe tomatoes, tamari, miso, sauerkraut, dried sea vegetables, marmite, nutritional yeast, olives, balsamic vinegar, and mushrooms. Roasting, caramelizing, browning, and grilling increase umami by freeing glutamate from proteins (10).
Don’t Overdo the Oxalate
Some plant foods are high in oxalate and spinach is extremely high. For most vegans, oxalate won’t be a problem, but if you decide to start juicing or blending your greens, make sure you don’t consistently use large amounts of the high oxalate greens—spinach, swiss chard, and beet greens—doing so can sometimes result in a kidney stone. See Oxalate for more info.
Low Cholesterol
In rare cases, some vegans might not get enough fat or calories to produce adequate amounts of steroid hormones, which are made from cholesterol.
Two studies have shown vegans to have sex hormones on par with meat eaters (11, 12), but one report showed vegan women to have lower levels of estrogen (13).
A few anecdotal reports provide some evidence that low cholesterol might be a problem for some vegans—see Bonzai Aphrodite’s story of regaining her health as a vegan, Facing Failing Health As A Vegan. In such cases, increasing saturated fat, such as by adding some coconut oil, could increase a depressed libido or resume menstruation.
Vitamins and Minerals: For the Long Haul
Although a vitamin or mineral deficiency is very unlikely to occur in only a few weeks or months as a vegan, there are some nutrients you need to pay attention to if you want to thrive over the long term.
Daily Needs
We provide the precise requirements and common sources for each nutrient below in our article, Daily Needs.
Vitamin B12
Vitamin B12 in vegan diets has been a source of controversy and myths (14). Although it rarely happens quickly, if you don’t get a reliable source of vitamin B12 through fortified foods or supplements, the chances are high that you will eventually find your health suffering.
Calcium
The need for calcium on vegan diets has also been surrounded by misleading claims with many vegan advocates saying that animal protein, including milk, is the main cause of osteoporosis in Western countries. Following this logic, it would make sense that vegans don’t need to worry about osteoporosis since we don’t eat animal protein.
The research actually shows that vegans, like nonvegans, should try to meet the same calcium recommendations as the greater population. Vegan diets tend to contain much less calcium than other diets, so we must make an effort to include good sources on a daily basis.
Vitamin D
More often than not, vegans who come to me with severe fatigue are suffering from vitamin D deficiency. This isn’t just a vegan problem as many people develop vitamin D deficiency, partially as a result of avoiding the sun. But vegans are at a slight disadvantage, on average, because we get less vitamin D in our diets. Make sure that you have a reliable source of vitamin D.
Iron
Iron is found in a wide range of plant foods and vegans tend to have iron intakes comparable to meat-eaters.
However, plant iron isn’t as easily absorbed as iron from meat and a small percentage of women develop iron-deficiency anemia after becoming vegetarian.
If you think you’re at risk: Make sure to include a good source of vitamin C at meals—it binds with iron creating a more easily absorbed complex. Avoid coffee and tea at meals as they decrease iron absorption.
Iodine
Iodine is important for thyroid health, but it’s a nutrient that most vegans rarely think about. A 2011 study showed that some vegans don’t get enough. Especially if you eat soy, you should make sure you have a source of iodine—either from seaweed, a supplement, or iodized salt.
Omega-3s
DHA is an omega-3 fatty acid that is important for cognition. A short time on a vegan diet is not likely to cause any sort of deficiency, but long-term vegans should make sure they’re getting enough omega-3s. Walnuts, canola oil, flaxseeds, or a DHA supplement are the most common ways to obtain omega-3s.
Vitamin A
There are many sources of vitamin A for vegans—especially orange vegetables—but you shouldn’t leave getting enough to chance. See your options in the picture below and eat one or two sources every day.
Zinc
An average vegan diet will meet or come close to the RDA for zinc, but some people might fall a bit short. Symptoms of zinc deficiency include catching frequent colds or developing cracks at the corners of your mouth. Supplement with 50–100% of the RDA if you suspect a deficiency.
Vegan Meals
To see general meal plans that a vegan might follow to meet nutrient needs, check out:
Good luck—and may you thrive on a vegan diet!
References
1. Fraser GE. Vegetarian diets: what do we know of their effects on common chronic diseases? Am J Clin Nutr. 2009 May;89(5):1607S-1612S. Epub 2009 Mar 25. Review. Erratum in: Am J Clin Nutr. 2009 Jul;90(1):248.
2.Appleby PN, Davey GK, Key TJ. Hypertension and blood pressure among meat eaters, fish eaters, vegetarians and vegans in EPIC-Oxford. Public Health Nutr. 2002 Oct;5(5):645-54.
3. Tonstad S, Stewart K, Oda K, Batech M, Herring RP, Fraser GE. Vegetarian diets and incidence of diabetes in the Adventist Health Study-2. Nutr Metab Cardiovasc Dis. 2013 Apr;23(4):292-9.
4. Key TJ, Appleby PN, Crowe FL, Bradbury KE, Schmidt JA, Travis RC. Cancer in British vegetarians: updated analyses of 4998 incident cancers in a cohort of 32,491 meat eaters, 8612 fish eaters, 18,298 vegetarians, and 2246 vegans. Am J Clin Nutr. 2014 Jun 4.
5. Tantamango-Bartley Y, Jaceldo-Siegl K, Fan J, Fraser G. Vegetarian diets and the incidence of cancer in a low-risk population. Cancer Epidemiol Biomarkers Prev. 2012 Nov 20.
6. Bradbury KE, Crowe FL, Appleby PN, Schmidt JA, Travis RC, Key TJ. Serum concentrations of cholesterol, apolipoprotein A-I and apolipoprotein B in a total of 1694 meat-eaters, fish-eaters, vegetarians and vegans. Eur J Clin Nutr. 2014 Feb;68(2):178-83.
7. Sabaté J, Ang Y. Nuts and health outcomes: new epidemiologic evidence. Am J Clin Nutr. 2009 May;89(5):1643S-1648S.
8. Dieting by DNA? Popular diets work best by genotype, research shows.
9. Jenkins DJ, Wong JM, Kendall CW, Esfahani A, Ng VW, Leong TC, Faulkner DA, Vidgen E, Greaves KA, Paul G, Singer W. The effect of a plant-based low-carbohydrate (“Eco-Atkins”) diet on body weight and blood lipid concentrations in hyperlipidemic subjects. Arch Intern Med. 2009 Jun 8;169(11):1046-54.
10. Is Umami a Secret Ingredient of Vegan Activism?
11. Thomas HV, Davey GK, Key TJ. Oestradiol and sex hormone-binding globulin in premenopausal and post-menopausal meat-eaters, vegetarians and vegans. Br J Cancer. 1999 Jul;80(9):1470-5.
12. Key TJ, Roe L, Thorogood M, Moore JW, Clark GM, Wang DY. Testosterone, sex hormone-binding globulin, calculated free testosterone, and oestradiol in male vegans and omnivores. Br J Nutr. 1990 Jul;64(1):111-9.
13. Goldin BR, Gorbach SL. Effect of diet on the plasma levels, metabolism, and excretion of estrogens. Am J Clin Nutr. 1988 Sep;48(3 Suppl):787-90. Review.
Fantastic, comprehensive information for anyone wondering about the plant-based lifestyle or already immersed in it.
Thank you, Annoula!
It’s always great to see rational, fact-based responses to the emotional and often false beliefs that seem to permeate our culture.
One point that I think is lost here is one of simple practicality: you honestly do not need to worry about getting enough of any one nutrient or another as long as you are eating a reasonably varied diet and getting enough calories.
More to the point, how many people in this country are diagnosed with a deficiency in any one of these nutrients? Vanishingly small, I’d bet and it pales in comparison to those diagnosed with heart disease, diabetes, hypertension, strokes, or any of the other maladies stemming from consuming animals.
Hi Dave–
Thank you for your comment on this and I completely agree that a meat-based diet is more likely to lead to some of the more common degenerative diseases and in that sense, meat-eaters have more to worry about than do vegans. However, the nutrients I put together that vegans should pay attention to are either nutrients that won’t necessarily be covered by simply eating a varied diet and do cause problems when they aren’t, or nutrients that can be a problem to a small, but not insignificant amount of vegans. There is no reason to panic, but you should go down the list and read them and make sure you’re covering your bases.
Hi Jack,
I’ve been a vegan for just over a year. I’ve had some hiccups along the way – feeling rundown, the reappearance of some patches of psoriasis on my elbows that had disappeared since childhood – so I take low supplements of B12, Zinc, and I was taking a supplement of Iodine (just over 100% RDA). I’ve always had really clear skin but now I have what looks like the start of acne. I stopped taking the iodine because I think it dates from when I started taking that. (I was taking B12 from the start, but Iodine only the past few months.)
– If it is the Iodine, do you know how long should it take to clear up?
– Is there anything apart from B12 and Iodine that can cause this, in a vegan diet? I do eat a lot of soy in the form of yoghurt, milk, tofu and edamame.
– Could it be the B12, even though I was taking B12 for months before my skin got bad?
Thanks in advance for any advice you can give me.
Sheena–
Small amounts of B12 shouldn’t cause acne. How much are you taking?
I see there’s a lot on the internet saying iodine can aggravate acne, but I didn’t find anything from a reliable source.
I’m wondering if you’re getting enough vitamin D? Do you pay attention to that in any way?
Hi Jack,
For B12, I take:
– about 4mcg of B12 in syrup, most days.
– nutritional yeast (2.2mcg per 5g) – probably about 2 tbsp a day.
– soy yogurt – (.38mcg B12 per 100g) – maybe 200g-300g per day. (I eat a lot of yogurt).
– margarine – (.5mcg per 10g) – maybe 30g per day?
– soy milk – (.38mcg per 100ml) – about 250 ml most days.
Vitamin D:
Occasionally take a 10 mcg tablet but not really that regularly. I was taking them regularly when my skin got bad and I actually stopped taking them along with the iodine. I get:
– yogurt – (.75mcg of D2 per 100g) – 200-300g a day.
– margarine – (.8mcg D2 per 10g) – 30g/day.
– soy milk (~1mcg of D2 per 100ml – I make porridge half and half with soy milk and a soy milk for kids that has twice the vitamin D in it, it averages just over 1 mcg) – 250ml/day.
So, now you say it, I think I’m getting about 300% my RDA of B12. Would that be enough to cause it?
Hi Sheena–
It’s extremely unlikely for 300% of the RDA of B12 to cause skin problems. Doses that do that tend to be more in the realm of 400 times the RDA (which is more like 2,000%).
Psoriasis is not likely to be diet-related. Mayo Clinic says that exposing the skin to small amounts of sunlight can help as can some topical vitamin D ointment, that’s why I though perhaps it could be related to a significant vitamin D deficiency but that is more theoretical than evidence-based. It’s not uncommon to get vitamin D levels tested and I recommend that vegans do that every few years just to make sure they’re getting enough.
Mayo Clinic info: http://www.mayoclinic.org/diseases-conditions/psoriasis/basics/definition/con-20030838
Good luck and I hope you find a solution!
Ok, thanks for the info! I’ll take the Vitamin D daily for a while and see if it clears up.
Cheers!
Hi, I’m back again! (Let me know if there’s a more appropriate forum for this). I had tests done and everything came back fine – nothing too low or too high, including D and B12. Meanwhile my skin has gotten worse. Is it possible it’s a soy intolerance? I use soy milk & soy yoghurt every day. I’ve tried to find info on this but I don’t know which sources are trustworthy.
Sheena–
The way to know if it’s a particular food is to eliminate the food for a few weeks and see if symptoms clear up. If they do, then add the food back in and see if they come back. If they do, you can be fairly certain it’s that food. Be aware that many problems are not food-related. I hope you find some relief soon!
Hey Jack,
For ALA, you wrote
“Add 0.5 g of uncooked ALA to your diet daily (see chart). This would be the equivalent of:
1/5 oz English* walnuts (3 halves)
1/4 tsp of flaxseed oil
1 tsp of canola oil
1 tsp ground flaxseeds”
However in your book Vegan For Life (great book) for ALA you say to have three to four times these amounts:
“Be sure that your diet includes three to four servings per day from the following list:
1 teaspoon canola oil
¼ teaspoon flaxseed oil
⅔ teaspoon hempseed oil
1 teaspoon walnut oil
2 teaspoons ground English walnuts or 2 walnut halves
1 teaspoon ground flaxseeds
½ cup cooked soybeans
1 cup firm tofu
1 cup tempeh
2 tablespoons soynuts” (p. 89)
Can you clarify this? Or am I missing something?
Thanks mate!
Josh–
The reason we increase the servings for the second list is because there are a number of foods that don’t contain as much ALA as all the foods in the first list, so you need to eat more of some of them to ensure you’re getting enough. We decided to expand the list of foods for the book, but I’ve stuck with my smaller list of foods that contain more ALA on VeganHealth.org to make sure people don’t just rely on random chance to get their ALA. I’m actually torn on which is the better tactic.
Thanks for your wonderful information on these very important facts,I’m a Vegan for the past year,and having tremendous results with my overall health.
My wife is not fully convinced that she can totally get the proper health benefits from plant base product alone.so this confirmation will encourage her to make a change. Thank you once more,and God bless.
I have been told by my Doctor that I should go on a plant based diet to control my numerous health issues.
Unfortunately I cant have so many of the veggies out there and since beans really hurt my stomach along with garlic and onions, I am having a hard time choosing what to eat.
When I eat Fish and lean chicken the pain is non existent. Any suggestions? I have been diagnosed in the past with chronic gastritis.
I’m really sorry to hear about your health issues. I’d recommend you reach out to a registered dietitian who has experience with plant-based diets. Here’s a list of such people who do remote personal counseling:
https://vegetariannutrition.net/find-a-registered-dietitian/
Good luck and I hope you find a way to feel better and make a plant-based diet work.
Thank you. I am almost there.. I love my eggs.. otherwise use a lot of plant based foods in my meals already, but not completely veg. Your information above is very comprehensive and insightful to address my concern about getting the right amount of nutrients. Thanks again