Of the many ways there are to eat, vegan diets may require a little more planning than most to make sure you’re meeting all your nutritional needs. “There are some vitamins and minerals that are more challenging to get from plants alone,” says Kalee Eichelberger, a registered dietitian with Orlando Health Orlando Regional Medical Center in Florida.
“This is in part due to the fact that vegetarians and vegans, by nature of their plant-based diets, consume more phytic acid, which is naturally an inhibitor of minerals like iron and zinc,” says Carly Knowles, pregnancy dietitian and doula based in Portland, Oregon.
Key Nutrients for Vegans
Key nutrients that vegans should pay attention to include:
When it comes to getting all your nutrients, vegans should be most concerned about their vitamin B12 intake. “A well planned vegan diet can meet all nutrient needs with the exception of vitamin B12,” says Dena Champion, a registered dietitian with the Ohio State University Wexner Medical Center in Columbus.
“Vegetarians and vegans are at a higher risk of developing a vitamin B12 deficiency as its most bioavailable form is found primarily in animal products,” Eichelberger says. B12 is important in energy production and formation of red blood cells.
The recommended dietary allowance for healthy adults is 2.4 micrograms of B12 per day.
Eichelberger recommends making sure you’re consuming plenty of B12-fortified foods, such as:
- Plant-based milks. Check the label to make sure the specific product is fortified with B12, as not all of them are. The U.S. Department of Agriculture reports that a cup of fortified soy milk contains more than 85% of the daily value of vitamin B12.
- Breakfast cereals. Fortified cereals vary in how much B12 they provide. Check the nutritional facts label on the box to see how much B12 your favorite cereal can offer.
- Nutritional yeast. Nutritional yeast is fortified with synthetic B12, just like some plant-based milks and breakfast cereals are. The USDA reports that a quarter cup (15 grams) of large flake nutritional yeast contains 730% of your daily value of vitamin B12.
- Plant-based meat alternative products. Meat and other animal products are rich sources of vitamin B12, so many manufacturers of plant-based meat alternatives add vitamin B12 to their products. Check the nutritional label to see whether your favorite veggie burger has added B12.
If you’re still not able to meet the daily recommended allowance of vitamin B12, it may be time to try a supplement. Eichelberger recommends taking cyanocobalamin of vitamin B12 or methylcobalamin, two synthetic forms of vitamin B12 that can be taken in pill or powder form, or in some cases can be administered as a monthly injection. Injections of B12 are typically only advised for people with a documented B12 deficiency.
Iron is another nutrient that vegans and vegetarians should pay attention to. Like vitamin B12, iron is critical in the formation of red blood cells and also helps ensure that your cells can adequately use the oxygen from your lungs.
Eichelberger says that while many vegan foods contain iron, this form of iron, called non-heme iron, isn’t absorbed as well by your body when compared to animal-based sources of iron, called heme sources.
The National Institutes of Health Office of Dietary Supplements reports the recommended daily allowance of iron for adults aged 19 to 50 years is 9 milligrams for men and 18 milligrams for women. Pregnant women should consume 27 milligrams of iron daily and 9 milligrams daily during lactation.
Vegans are at increased risk of becoming deficient in vitamin D, Eichelberger says, because “the best food sources of this nutrient are in fatty fish, dairy, seafood and eggs.”
Vitamin D is integral to calcium absorption and for nerve and muscle signaling. This fat-soluble vitamin is unique in that your body can actually make it in your skin when it’s exposed to UV light. Adults aged 19 to 70 need 15 micrograms or 600 IU of vitamin D daily, while adults over age 71 should get 20 micrograms or 800 IU of vitamin D daily.
If a combination of diet and sunlight still don’t have you meeting your daily intake of vitamin D, Eichelberger says it may be time for a supplement.
Calcium is a vitamin of concern for some vegetarians, Eichelberger says. Calcium helps keep bones strong and is important for electrical signaling of muscles, especially the heart. It’s found in dairy products, but also in leafy green veggies, tofu, almonds and seeds.
“Vegans consuming too little dietary calcium should also consider taking a daily supplement especially if they’re consuming less than 525 milligrams per day.” Adult men aged 19 to 70 should aim for 1,000 milligrams of calcium per day. Women should also aim for 1,000 milligrams daily until age 70, at which point they need 1,200 milligrams daily.
Iodine is important for the manufacture of thyroid hormones, which control metabolism and support bone and brain development during pregnancy and infancy. Adults should consume 150 micrograms of iodine per day, while pregnant women should aim for 220 micrograms. Breastfeeding women should get 290 micrograms per day.
Iodine is found in fish products, such as cod, tuna and shellfish and dairy products including milk, yogurt, eggs and cheese. But for vegans who don’t consume any of these products, it can be challenging to get enough. Iodized salt is a widely available form of salt that’s fortified with iodine, but fancy salts like sea salt, Himalayan salt or kosher salt, are not typically iodized. Check the label for the terms “iodized” or “iodide.”
Zinc is a key nutrient in supporting immune health and making proteins and DNA. During pregnancy and childhood specifically, adequate zinc supports proper growth and development. Men need 11 milligrams per day while women should consume 8 milligrams. However, pregnant and breastfeeding women need 12 milligrams daily.
Vegan Supplements During Pregnancy
Concerns about nutritional deficiencies in people following a vegan diet can become a little more challenging during pregnancy, Knowles says. Because phytic acid naturally inhibits absorption of some minerals – especially iron and zinc that are very important during pregnancy – it’s important for pregnant people following a vegan diet to pay close attention to their intake of all nutrients.
“Any plant-based diet while pregnant requires careful planning, consistent and adequate nutrient intake, and a serious supplement plan with compliance,” Knowles says. For some, she recommends making some exceptions to the no-animal product rule to help boost intake of important nutrients like iron and vitamin B12.
However, “if you’re unwilling to make exceptions to consume animal-based foods while pregnant, then I highly recommend you work with a pregnancy dietitian or a credentialed health practitioner who’s experienced with plant-based diets for pregnancy for close monitoring,” she says.
During pregnancy, Knowles says supplementation should be considered “a non-negotiable” for vegans. “Supplements provide a safety net to help fill in the gaps of your diet to ensure adequate levels of important pregnancy nutrients.”
If you are pregnant and following a vegan diet, Knowles recommends looking for a product that provides your recommended daily allowance of:
You may want to consider supplementing your protein intake as well, Knowles says. “In my clinical practice, I find that protein supplements are often needed to meet the high protein demands of pregnancy, even for those that eat animal protein. There are a lot of quality vegan protein supplements on the market, however, careful vetting is required to find one that contains quality ingredients and doesn’t include unnecessary ingredients like sugar or contaminants such as heavy metals.”
Choosing Vegan Supplements
It’s always best to consult with your health care provider before beginning to take any supplement. They can offer tailored advice and support to help you determine whether you need a supplement at all, and, if so, how to select the right supplement for your specific needs.
Champion recommends keeping a food journal for a few weeks to determine whether you’re meeting your nutrient needs. “Some people may be surprised about what they find. For example, you may assume that you meet your iron needs because you eat high-iron plant foods. However, after tracking, you may find that most days you’re not nearly meeting your needs for iron.”
If that’s the case, she recommends “speaking with a dietitian to determine ways to meet these needs by incorporating more high-iron foods or discussing how much and what kind of iron supplement to take daily.”
It’s also important to note that over-the-counter dietary supplements are not regulated the same way prescription supplements and medications are. Eichelberger recommends selecting brands that have a United States Pharmacopeia seal. “USP is a globally recognized, nongovernmental, nonprofit organization that sets standards for identity, strength, quality and purity of medicines, food ingredients and dietary supplements.”
Champion adds that NSF certification can also be a sign that the product is what it claims to be, but it’s always best to talk with an expert. “Unfortunately, I see patients who have spent astronomical amounts of money on supplements that, at best, aren’t helpful, but, at worst, may be harmful. Please seek out the help of a registered dietitian who specializes in vegan diets to help you sort this out.”
Knowles recommends “avoiding supplements that have been contaminated with other substances such as heavy metals or pharmaceutical drugs,” which is “another reason to make sure you’re only taking quality and reputable supplements.”
Before your buy any supplement, be sure to read the packaging carefully and specifically check that all the ingredients are plant-sourced versus animal derived.
Eichelberger notes that some non-vegan items could be hiding in some supplements, including:
“Some vitamins and minerals may be sourced from animal derivatives as well. To avoid these, make sure to buy exclusively vegan products and brands,” Eichelberger cautions.
Lastly, “talk to your health care provider before beginning any supplement regimen, especially if you are pregnant or breastfeeding,” Eichelberger says.
Champion notes that while you might need to consume fortified foods or take a supplement to meet all your nutritional needs, that doesn’t mean following a vegan diet is unhealthy.
“A vegan diet can absolutely be a healthy diet. Vegans often consume more fruits, vegetables, whole grains and fiber than the average American. And while you can meet nearly all nutrient needs on a vegan diet, a supplement can really help fill in the gaps when needed. There’s nothing wrong with using a supplement to help you meet nutrient needs and make life a little easier.”