Just days before everyone was talking about the Voracious [ex-] Vegan story, I received a severe scolding from a reader for my stance on supplements (this was in response to my post on omega-3s). She was adamant about the fact that “whole plant foods” can easily provide everything we need.
An effort to prove that a whole foods vegan diet is the ideal or foolproof diet of all humans gives rise to all kinds of potentially harmful myths. These include the unfounded position that vegans can meet vitamin B12 needs by consuming unwashed organic produce, or that we have lower calcium needs than omnivores, or that it’s been “proven” that no one needs long chain omega-3 fats in their diet.
If these claims make vegan diets look easy and ideal, but they jeopardize health—well, that just seems like a pretty poor trade-off. There are many reasons why people abandon vegan diets, and bad nutrition advice from within the vegan community is probably one of them.
Many ex-vegans claim that they supplemented with vitamin B12 and still developed a deficiency. I have no trouble believing it when I read the incorrect or inadequate advice that some vegan advocates provide. These include the suggestion that you may wish to take an “occasional” small B12 supplement after you’ve been vegan for three years. Some resources on vegan diets don’t even bother with any specifics about dosages or absorption issues regarding vitamin B12.
Here is how those who are supplementing with B12 could become deficient:
·They waited too long to start supplementing and then didn’t take a high enough dosage to rebuild stores.
·They think they are supplementing “faithfully,” but are really just taking a small dose of B12 a couple of times a week.
·They aren’t chewing their B12 tablet or using a sublingual pill and aren’t digesting the pills that are swallowed whole.
·They are using methylcobalamin instead of cyanocobalamin, not realizing that the dosage requirements for methylcobalamin could be much higher—maybe as high as 1,000 to 2,000 micrograms per day (as opposed to the 25 micrograms of cyanocobalamin that are probably sufficient.)
Any of these would be a good example of how a conscientious vegan could fail to get adequate B12 simply because the vegan nutrition information they read was inadequate.
This is where we are with vegan diets: We promote a way of eating that is well outside the mainstream and, therefore, are challenged to prove its safety every step of the way. The things at stake are the health of the people to whom we promote it, and the lives of the billions of animals who depend on us to make veganism a realistic and safe choice for everyone. So we’d be very wise to err on the side of caution in making recommendations about how to eat.
Vegans do need supplements or fortified foods, and admitting that a vegan diet is not automatically pure perfection is way better than getting sick.
Here, then, are supplements (or fortified foods) that vegans need:
All vegans:
Vitamin B12. You can’t get enough by eating unwashed organic produce or mushrooms grown in B12-rich soil. The recommended dose is 25 to 100 micrograms per day or 1,000 micrograms 2-3 times per week. If you have not been taking B12 for a while, start out with 2,000 micrograms daily for several weeks. Or get a blood test to see where you are and whether you might need a more therapeutic dose.
Most vegans:
Vitamin D. If you live where it’s sunny and warm all year and you spend time outdoors without sunscreen, you can make enough. The rest of us need a supplement or fortified foods (just like omnivores do) supplying 1,000 I.U.s of vitamin D. (This amount is well above the RDA for vitamin D but most experts think it’s warranted.
Iodine. Omnivores get most of their iodine from dairy products, which pick up iodine from solutions used to clean cows and equipment on dairy farms. Vegans who regularly eat sea vegetables may get enough, but the content varies a lot as it does for sea salt and other “natural” salts. Miso, which some vegans prefer to use in place of salt—because it’s a whole food—is not usually a good source of iodine. The only reliable sources are iodized salt or a supplement providing around 90 micrograms per day.

Some vegans:
Calcium. We don’t know if vegans have lower needs, but the old “low protein diets reduce calcium needs” theory has taken some real hits in the past years. Based on current understanding–which is admittedly pretty poor–we vegans should strive for the RDA. Our ancestors didn’t drink milk and got all the calcium they needed from wild greens. And even though modern cultivated greens have less, we could get enough calcium just from these foods, too. But the recommendation to eat four or more cups of cooked greens per day makes veganism a hard sell. Without fortified foods, many vegans fall short on calcium. (So do most omnivores; the food industry doesn’t fortify orange juice or instant oatmeal with calcium as a favor to vegans. Those foods are marketed to omnivore women.)

Iron. Young women with heavy periods may have a tough time keeping up with iron needs, and again, this is not a problem that is specific to vegans. Rates of iron deficiency anemia are actually very high among pre-menopausal omnivore women. It can help to take a low dose supplement (high doses can be hard on the stomach) with orange juice to boost absorption, or to include some fortified foods in the diet. There is some evidence that taking supplements of the amino acid L-lysine boosts absorption of supplemental iron.
Possible supplement requirements
DHA: 200 to 300 mg several times a week. It may be a good idea, but we don’t know for sure. I take this amount almost daily and would recommend it in particular for anyone who is prone to depression.
Sound like a lot of supplements? Well, here is some perspective: Omnivores get their vitamin D from fortified foods (cow’s milk is not a natural source of this nutrient) and their iodine from accidental contamination of dairy foods. Many omnivores—women especially—depend on supplements to meet calcium and iron needs. And the Institute of Medicine recommends that everyone over the age of 50 should add vitamin B12 supplements or fortified foods to their diet since it becomes increasingly difficult to digest and absorb the vitamin B12 in animal foods with aging.
Vegans may need to work a little bit harder to meet nutrient needs, but that’s a small trade-off for making choices based on compassion and justice for animals.