One common concern about vegan diets is whether they provide your body with all the vitamins and minerals it needs.
Many claim that a whole-food, plant-based diet easily meets all the daily nutrient requirements. Some even encourage vegans to avoid all supplements. Despite being well intended, this type of advice can do more harm than good.
Here are 7 nutrients that you may need to supplement with while on a vegan diet.
1. Vitamin B12 - Several studies show that while anyone can have low vitamin B12 levels, vegetarians and vegans have a higher risk of deficiency. This seems especially true for vegans who are not taking any supplements.
Vitamin B12 is important for many bodily processes, including protein metabolism and the formation of oxygen-transporting red blood cells. It also plays a crucial role in the health of your nervous system. Too little vitamin B12 can lead to anemia and nervous system damage, as well as infertility and bone and heart disease.
The daily recommended intake is 2.4 mcg per day for adults, 2.6 mcg per day during pregnancy, and 2.8 mcg per day while breastfeeding. It’s important to keep in mind that vitamin B12 is best absorbed in small doses. Thus, the less frequently you ingest vitamin B12, the more you need to take.
Finally, your ability to absorb vitamin B12 decreases with age. Therefore, the Institute of Medicine recommends that everyone over the age of 51 — vegan or not — consider fortified foods or a vitamin B12 supplement.
2. Vitamin D - is a fat-soluble vitamin that helps enhance the absorption of calcium and phosphorus from your gut. This vitamin also influences many other bodily processes, including immune function, mood, memory, and muscle recovery.
The recommended daily allowance (RDA) for vitamin D for children and adults is 600 IU (15 mcg) per day. The elderly, as well as pregnant or lactating women, should aim for 800 IU (20 mcg) per day (22). That said, some evidence suggests that your daily requirements are far greater than the current RDA.
The best way vegans can ensure they’re getting enough vitamin D is to have their blood levels tested. Those unable to get enough from fortified foods and sunshine should consider taking a daily vitamin D2 or vegan vitamin D3 supplement.
Although vitamin D2 is probably adequate for most people, some studies suggest that vitamin D3 is more effective at raising blood levels of vitamin D.
3. Long-chain omega-3 fatty acids can be split into two categories:
• Essential omega-3 fatty acids: Alpha-linolenic acid (ALA) is the only essential omega-3 fatty acid, meaning you can only get it from your diet.
• Long-chain omega-3 fatty acids: This category includes eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). They are not considered essential, because your body can make them from ALA.
Long-chain omega-3 fatty acids play a structural role in your brain and eyes. Adequate dietary levels also seem important for brain development and reducing the risk of inflammation, depression, breast cancer, and attention deficit hyperactivity disorder (ADHD).
Vegans tend to have lower blood and tissue levels of long-chain omega-3 fatty acids. Therefore, they may benefit from supplementing with EPA and DHA. Most health professionals agree that 200 300 mg per day should be sufficient.
4. Iron - is a nutrient used to make new DNA and red blood cells, as well as carry oxygen in the blood. It’s also needed for energy metabolism.
Too little iron can lead to anemia and symptoms like fatigue and decreased immune function.
The RDA is 8 mg for adult men and post-menopausal women. It increases to 18 mg per day for adult women, and pregnant women should aim for 27 mg per day.
The best way to determine whether supplements are necessary is to get your hemoglobin and ferritin levels checked by your health practitioner.
Unnecessary intake of supplements like iron can do more harm than good by damaging cells or blocking the absorption of other minerals.
5. Calcium - is a mineral that’s necessary for good bone and teeth health. It also plays a role in muscle function, nerve signaling, and heart health.
The RDA for calcium is set at 1,000 mg per day for most adults and increases to 1,200 mg per day for adults over the age of 50.
Plant sources of calcium include bok choy, kale, mustard greens, turnip greens, watercress, broccoli, chickpeas, calcium-set tofu, and fortified plant milks or juices. However, studies tend to agree that most vegans don’t get enough calcium.
For this reason, all vegans are encouraged to aim for the RDA, making sure they consume at least 525 mg of calcium per day. Supplements should be used if this can’t be achieved through diet or fortified foods alone.
6. Zinc - is a mineral that’s crucial for metabolism, immune function, and the repair of body cells. An insufficient intake of zinc can lead to developmental problems, hair loss, diarrhea, and delayed wound healing.
The RDA for zinc is currently set at 8–11 mg per day for adults. It increases to 11–12 mg for pregnant women and 12–13 mg for lactating women.
Few plant foods contain high amounts of zinc. Moreover, zinc absorption from some plant foods is limited due to their phytate content. Thus, vegetarians are encouraged to aim for 1.5 times the RDA.
Vegans concerned about their zinc intake or those with symptoms of a deficiency may consider taking a daily zinc gluconate or zinc citrate supplement that provides 50–100% of the RDA.
7. Iodine - Getting enough iodine is crucial for healthy thyroid function, which controls your metabolism. An iodine deficiency during pregnancy and early infancy can result in irreversible intellectual disability.
In adults, insufficient iodine intake can lead to hypothyroidism. This can cause various symptoms, such as low energy levels, dry skin, tingling in your hands and feet, forgetfulness, depression, and weight gain.
The RDA for adults is 150 mcg of iodine per day. Pregnant women should aim for 220 mcg per day, while those who are breastfeeding are recommended to further increase their daily intake to 290 mcg per day. Half a teaspoon (2.5 ml) of iodized salt is sufficient to meet your daily needs.
Vegans who do not want to consume iodized salt or eat seaweed several times per week should consider taking an iodine supplement.
The bottom line
Well-planned vegan diets can fulfill your nutritional needs. That said, certain nutrient requirements may be difficult to achieve through diet and fortified foods alone.
This is especially true for vitamin B12, vitamin D, and long-chain omega-3s.
All vegans who are unable to meet their dietary recommendations through diet alone should consider taking supplements. Still, it’s best to speak with your healthcare provider before beginning a new supplement regime.