By Virginia Messina, MPH, RD
Going vegan, or just taking a few steps in that direction, can deliver some important health benefits. Diets built primarily on plant foods are associated with lower cholesterol levels and reduced risk for type-2 diabetes. Plant foods also contain numerous compounds that have anti-cancer properties. Some people find that replacing meat, dairy and eggs with fiber-packed plant foods helps them shed weight, too. The benefits of being mostly or entirely vegan vary between individuals, though, depending on other lifestyle factors, your genes, and your previous diet.
It isn’t exactly clear how you need to eat to maximize the benefits of plant foods. But replacing refined grains with whole grains, boosting your intake of fruits and vegetables, and eating more legumes and healthy fats is definitely a good place for most people to start.
While simply eating a variety of whole plant foods will increase your odds of avoiding chronic diseases, meeting nutrient needs on a vegan diet does require some attention. It’s certainly possible to switch to a vegan diet, and to have your intake of one or more nutrients drop from satisfactory to deficient. This article will show you the main things to keep in mind in order to cover your nutritional bases on a mostly or totally vegan diet. Nothing presented here is all that difficult, it’s just that it isn’t exactly intuitive. Vegan diets are relatively new to most cultures which means some of your nutrients will be coming from foods you previously ate rarely or not at all. Once you learn a few basics about menu planning, though, following a healthful vegan diet becomes second nature.
The nutrients that require extra attention in vegan diets are:
Even though, in a Western omnivorous diet, these nutrients are typically associated with animal foods, everything except B12 and vitamin D is easily found in vegan foods (and I’ll cover how to meet your B12 and D needs in this article as well.)
You may have heard that it’s impossible for vegans to fall short of protein needs if they eat enough calories and choose whole plant foods. That’s not quite true, though. While we never see vegans with overt protein deficiency, it doesn’t mean that all vegans consume optimal amounts. Marginal or suboptimal protein status can take a toll on health, affecting bone health and muscle strength, for example.
In particular, if your diet doesn’t include legumes, it may not provide optimal amounts of all of the essential amino acids. These are the building blocks of protein and some of them, the essential amino acids, must come from food. Vegan diets that don’t include legumes (this food group includes beans, soyfoods and peanuts) could easily fall short of one particular essential amino acid called lysine.
Two servings per day of legumes are likely to provide sufficient lysine, and three servings delivers an extra margin of safety. Older people or anyone on a weight loss diet might want to aim for even more of these foods.
Two or three daily servings of legumes may sound like a lot, but the servings are probably smaller than you think. Any of the following counts as a serving of legumes:
- ½ cup cooked dried beans or lentils
- ½ cup tofu or tempeh
- 2-3 ounces veggie meat
- 1 cup soymilk or milk made from pea protein (but not other plant milks since most are too low in protein)
- ¼ cup peanuts or soynuts
- 2 tablespoons of peanut butter
Even if beans are relatively new to your diet, increasing your intake of legumes is easy. Here are just a few examples of familiar menu items that feature legumes.
- Peanut butter and jelly (or sliced banana) sandwiches
- Scrambled tofu
- Baked tofu
- Veggie burgers
- Hummus wraps
- Lentil soup
- Vegetables with peanut sauce
- Tossed salads topped with soynuts
- Bean burritos
- Cereal with soymilk
- Tacos with veggie “ground beef”
Iron and Zinc
Whole grains and beans are especially rich in iron, which tends to be abundant in plant-based diets. But the iron in these foods is bound to compounds called phytates, which inhibit its absorption. Vitamin C can break the bond between iron and phytate, and thereby measurably boost iron absorption.
The best way to meet your iron needs as a vegan is to include beans and whole grains in your menus and to include vitamin C-rich foods in meals as often as possible. Rich sources of vitamin C include citrus fruits and juices, cantaloupe, kiwifruit, mango, papaya, pineapple, strawberries, broccoli, Brussels sprouts, peppers, tomato juice, cabbage, and cauliflower.
The best sources of zinc in vegan diets are whole grains, legumes, nuts and especially seeds. Although, like iron, zinc is also bound to phytates, vitamin C has little effect in making zinc more available. Certain food preparation practices enhance zinc absorption, though. When whole grain bread is leavened with either yeast or sourdough, the zinc in the bread becomes much more available. Sprouting grains and legumes helps with zinc absorption, too.
Vegan foods don’t contain active vitamin A, but that’s not an important concern since a number of vegetables provide compounds that the body easily converts to vitamin A. These vitamin A precursors, which include the antioxidant beta-carotene, are abundant in dark leafy vegetables, especially kale and spinach, and in deep orange vegetables like winter squash (including pumpkin), sweet potatoes and carrots. Just a serving or two of these vegetables each day will provide plenty of vitamin A.
One nutrient that can be elusive in vegan diets is an essential fat called alpha-linolenic acid (usually abbreviated as ALA). This is an essential omega-3 fat that is found in just a handful of plant foods. To meet your body’s needs, it’s important to include any of the following in your diet every day:
- 1 tablespoon of ground flaxseed (note that it has to be ground; otherwise you won’t absorb the ALA)
- 1 teaspoon of flaxseed oil
- 4 walnuts
- 1 tablespoon of walnut, hempseed, soy or canola oil
- 2 teaspoons of chia seeds
Two other omega-3 fats, called DHA and EPA, aren’t considered essential in the diet because the human body can synthesize them (but only if it receives the necessary ALA first). Unfortunately, the conversion of these fats is fairly inefficient. Since DHA and EPA may be linked to heart and brain health, many health experts recommend including them in your diet. Although most people get DHA and EPA from fatty fish or fish oil supplements, vegan options are available. The omega-3 fats in vegan DHA/EPA capsules come from microalgae, which happens to be the same place that fish get their omega-3 fats.
Don’t hesitate to include other fat-rich foods in your diet, too, if you like them. Low-fat diets are based on an outdated understanding of nutrition that’s been largely discredited. Current recommendations support a wide range of fat intakes for good health, anywhere from 20 to 35 percent of daily calories. (This translates to 22 to 39 grams of fat for every 1,000 calories you eat.) What matters most isn’t how much fat you consume, but rather the type of fat you choose.
For example, tree nuts like almonds, cashews, walnuts, and pecans are linked to reduced risk for heart disease. Soyfoods, which are higher in fat than other legumes, are rich in isoflavones, compounds that may reduce cancer risk and might improve artery health. Extra-virgin olive oil is a unique source of certain compounds with anti-inflammatory properties. Seeds and avocados can help vegans meet their zinc requirement. With these things in mind, replacing animal fats with fats sourced from plant foods will tend to make your diet healthier.
Calcium intake is important for everyone, including vegans. Older research suggested that vegans might not need as much calcium as omnivores. The theory asserted that animal protein pulled calcium out of bones, raising requirements for those who ate lots of meat, milk and eggs. These claims have not held up under scrutiny, and it turns out that protein of any sort is probably good for bones, not bad.
While it’s important to consume adequate calcium, it’s doubly important to choose your calcium from sources where absorbability is high. Calcium absorption is good from fortified plant milks and tofu made with calcium sulfate. Absorption is also good from certain leafy green vegetables like kale, bok choy and turnip greens. Unfortunately, absorption from beans, nuts and seeds is quite a bit lower and it’s especially poor from some oxalate-rich vegetables like spinach and Swiss chard.
A good rule of thumb for getting sufficient calcium on a vegan diet is to consume at least two cups per day of foods rich in well-absorbed calcium. These include cooked Chinese cabbage, turnip greens, mustard greens, collards, tofu made with calcium sulfate, fortified plant milks, and fortified juices. Then aim to eat at least a few servings of other foods that provide more moderate amounts of calcium like beans, almond butter, soaked almonds, broccoli, kale, okra, sweet potatoes, figs, navel oranges, corn tortillas, and blackstrap molasses.
If you are over 50, try to eat at least three cups per day of foods that are rich in well-absorbed calcium since older people are often less efficient at absorbing calcium. If you don’t eat these foods regularly or are otherwise worried about meeting your needs, it’s wise to take a small daily supplement of 300 mg or so. Calcium pills should be taken with meals in order to reduce the risk of kidney stones.
The internet abounds in resources sharing misleading information about vitamin B12, namely unfounded claims that vegans don’t need to worry about it. But nutrition experts are in clear agreement that there are only two reliable sources of vitamin B12 for vegans. These are foods fortified with this nutrient and supplements.
Contrary to popular belief, sea vegetables, fermented foods and organic vegetables don’t provide vitamin B12. Nutritional yeast often contains significant B12, but only if it’s grown on a B12-rich medium. And while people can store significant amounts of vitamin B12 in their livers, this is not a reliable source of the vitamin for anyone.
When you go vegan or become nearly vegan you should start taking B12. There is no persuasive reason to wait, and every reason to start right away. Vitamin B12 deficiency results in anemia and can also lead to nerve damage—irreversible in some cases—so it’s essential to make sure you get enough.
Figuring out appropriate dosages of B12 is tricky because of the way the vitamin is absorbed. It’s absorbed best in small frequent doses which means you need larger and larger amounts of B12 the less often you consume it.
Here are three ways to meet vitamin B12 needs. They all refer to the cyanocobalamin form of the vitamin, which is the only one proven reliable as a supplement.
- Take a daily supplement providing 25 to 100 mcg of vitamin B12.
- Take a supplement providing 1,000 mcg of vitamin B12 twice per week. Opt for chewable or “sub-lingual” tablets (which you allow to dissolve under your tongue), since they may allow for greater absorption.
- Eat two servings per day of foods fortified with at least 2 to 3.5 mcg of vitamin B12 each. You’ll need to eat these servings at least 4 hours apart to allow for optimal absorption.
Humans evolved to make vitamin D when bare skin is exposed to strong summer sunlight. But smog, clouds and sunscreen all block vitamin D synthesis. Older people and people with darker skin need more sun exposure to make vitamin D. In temperate climates, winter sunlight is often too weak for adequate vitamin D synthesis. Exposing your face and arms (without sunscreen) to midday summer sunlight for 10 to 20 minutes per day, or 30 minutes if you’re over 70, should provide you with enough vitamin D. If you aren’t regularly getting this amount of sun exposure, you’ll need a dietary source.
Vitamin D occurs naturally in eggs and some types of fish, but the amounts are too low to meet daily needs. This means that many people, vegan or not, need vitamin D supplements or fortified foods to avoid deficiency.
The most common form of vitamin D in foods and supplements is vitamin D3, which is almost always derived from animals. Vitamin D2 usually comes from yeast and until recently was the only vegan form of the vitamin. Although it’s a little harder to find, vegan D3 supplements are now increasingly available. Recommended intake of vitamin D is 600 IUs per day.
The body needs iodine for a healthy thyroid gland. Although plant foods provide varying (and generally small) amounts of iodine, the most common sources for many people are iodized salt and dairy products. The iodine in cow’s milk comes primarily from cleaning solutions applied to udders prior to milking.
Although sea vegetables can be rich in iodine, their levels vary considerably. The amount of iodine in land plants varies, too, depending on where they grow.
A small amount of additional iodine, from either ¼ teaspoon of iodized salt per day or a supplement providing 75 micrograms of iodine three or four times per week can help you meet your needs.
Five Simple Guidelines for a Healthy Vegan Diet
If you find wading through all of this detail a little overwhelming, don’t worry. Instead of focusing on individual nutrients, consider a few easy big-picture things you can do to improve the quality of your diet. The following five guidelines pull the above information into simple steps for eating a healthy, well-balanced vegan diet.
- Eat at least three servings per day of beans, tofu, tempeh, soymilk, veggie meats, peanuts or peanut butter.
- Consume a wide variety of fruits and vegetables, including leafy greens and dark orange vegetables plus good sources of vitamin C like peppers, citrus fruit, and strawberries.
- Get most of your fat from healthy sources, like olive oil, nut butters, avocados, and seeds. Be sure to eat a good source of the essential omega-3 fat found in flaxseed, hempseed, canola oil, and walnuts. If you like them, include nuts, extra-virgin olive oil, and avocado as condiments in your meals.
- Eat two to three cups of calcium-rich foods every day including fortified plant milks, and cooked kale, collards, bok choy, turnip greens, or tofu made with calcium sulfate.
- Don’t shun supplements. All vegans need vitamin B12 from supplements or fortified foods. Most also need a supplement of vitamin D, at least in the winter months. Vegan DHA and EPA supplements can be good insurance. If you don’t regularly use iodized salt, an iodine supplement is a good idea. Vegan.com maintains a supplements page that provides current and helpful information.
Avoid Needless Dietary Restrictions
Placing needless restrictions on food choices can make it harder to meet nutrient needs and also harder to stick with your vegan diet. Unfortunately, the vegan and raw foods literature is full of advice that, despite being presented in forceful terms, doesn’t have a leg to stand on in terms of of being evidence-based. More restrictive versions of vegan diets, like raw foods or very low-fat patterns, have no advantages over diets that include cooked foods and higher fat foods. While it’s smart to eat plenty of vegetables, fruits, whole grains, beans, nuts and seeds, there is no reason to avoid vegan meats, plant milks, oils, or vegan treats in your meals. These foods not only make vegan diets more practical, but some contribute important nutrients. There is no evidence that vegans who shun these foods are any healthier than those who include them in meals.
And finally remember that a vegan diet provides no guarantee that you’ll never experience health problems. While plant-based diets are associated with lower risks for cancer, heart disease, and diabetes, vegans can still be struck by these diseases. No diet, whether vegan or otherwise, can guarantee robust health and a long life. But by paying attention to the guidance I’ve offered in this article, you can absolutely follow a compassionate and environmentally-friendly diet that will give you an edge against chronic disease.
Ginny Messina MPH, RD publishes TheVeganRD.com. She has co-authored a number of vegan-oriented books including Vegan For Life, Vegan For Her, Never Too Late to Go Vegan, Even Vegans Die, and The Dietitian’s Guide to Vegetarian Diets.