The 5 Best Supplements for Vegetarians, According to a Dietitian

Following a vegetarian diet comes with a lot of health-related advantages, such as a reduced risk of chronic disease, according to August 2019 research in the ​Journal of the American Heart Association​.

But excluding eating meat and fish from your diet could also mean losing out on the nutrients they provide, says Mahmud Kara, MD, a doctor who spent his early career treating patients at the Cleveland Clinic and later founded KaraMD.

And with time, nutritional deficiencies can lead to certain health issues, Dr. Kara says. For example, meat proteins offer a lot of iron and vitamin B12, and if you're lacking in them, conditions like anemia may arise.

But that doesn't mean you should avoid this type of diet. "There are plenty of omnivorous dietary patterns that lack certain nutrients and also require supplementation," says Ryan Andrews, RD, principal nutritionist and adviser for Precision Nutrition.

That is, it's not just vegetarians who find themselves needing to be thoughtful about their dietary choices, or sometimes reaching for supplements.

If you do follow a meatless diet, it's helpful to know what vitamins vegetarians should take or get more of from food sources. This guide will help you make sure you're getting more of the nutrients you need.

"One of the most important nutrients that vegetarians may experience a shortfall with is vitamin B12," Dr. Kara says. This vitamin helps your body make red blood cells, create DNA and keeps your nervous system functioning.

Many foods high in vitamin B12, such as beef, chicken and tuna are off-limits for vegetarians. "This vitamin is not found in plant foods and the amount in dairy and eggs is quite low. If your diet is highly plant-based, adding a B12 supplement may be needed," Andrews says.

And science backs this up. Research shows that many vegetarians have low levels of B12, and it's advised that people who eat a meatless diet get more of it from fortified foods or supplements, according to the Harvard T.H. Chan School of Public Health.

Vitamin B12 is available in several forms — any of them can work as a vegetarian supplement, such as cyanocobalamin, methylcobalamin or hydroxocobalamin, Andrews says.

Adults should get 2.4 micrograms of vitamin B12 per day, according to the National Institutes of Health Office of Dietary Supplements (ODS). People who are pregnant or breastfeeding need a bit more.

According to the Harvard T.H. Chan School of Public Health, signs of a B12 deficiency include:

• Fatigue, weakness
• Nerve damage with numbness, tingling in the hands and legs
• Memory loss, confusion
• Depression
• Anemia
• Dementia

Along with dairy products, such as milk and eggs, there are many vegetarian foods, such as cereal and nutritional yeast that are fortified with this vitamin, per the ODS.

Iron helps to distribute oxygen from the lungs throughout your body, including to your muscles, per the ​​U.S. National Library of Medicine (NLM).

Meat contains heme iron, which your body absorbs easily. In contrast, non-heme iron, which is found in plant foods, doesn't absorb as well.

"Vegetarian eaters have iron requirements that are about 1.8 times higher (due to lower overall iron absorption)," Andrews says. Your iron needs will be higher if you're physically active, or if you're a vegetarian who menstruates or donates blood, he adds.

Adult vegetarians assigned male at birth should aim for around 14.4 milligrams of iron each day, while adult vegetarians assigned female at birth should take in 27 milligrams daily, per the ODS. If you're breastfeeding and pregnant, your iron needs will be higher.

Without enough of this vitamin, you can develop an iron deficiency, which in turn could lead to anemia. Anemia is a condition in which your body doesn't make enough red blood cells, per the Mayo Clinic.

Eating vitamin C-rich foods alongside foods with iron can improve your absorption of the nutrient, Andrews says. You can also try to avoid foods that inhibit iron absorption, such as milk or tea, within two hours of eating an iron-rich meal.

Some vegetarian-friendly foods high in iron include:

• Spinach
• Lentils
• Chickpeas
• Almonds
• Sunflower seeds
• Tempeh

Another option is to get your iron through supplements.

Zinc is key for a well-functioning immune system, per the Mayo Clinic.

"​​Not getting enough can result in lowered immunity, hair loss, loss of appetite, dry eyes and a lowered white blood cell count," Andrews says.

And, as with iron, vegetarians need more of this vitamin — up to 50 percent more — than their meat-eating peers. That's because a legume- and grain-filled vegetarian diet is rich in foods with phytic acid — a compound that prevents zinc absorption in the body, per the ODS.

Beans, nuts, whole grains and dairy products are food sources of zinc that are appropriate for vegetarians, according to the ODS.

"If getting enough zinc from food is difficult (best to assess this with a doctor or dietitian), finding a good supplement can help," Andrews says.

Adult vegetarians should aim for between 12 and 16 milligrams per day, depending on their assigned sex at birth, per the ODS. People who are pregnant or breastfeeding require more zinc.

Vegetarians are not alone in falling short on vitamin D. "This nutrient is difficult to get from food alone, no matter how someone eats," Andrew says.

The so-called sunshine vitamin is important for healthy bones, as well as immune health and muscle function, per the Mayo Clinic. Many foods — such as milk and a container of OJ — are fortified with this vitamin.

"Eggs are another good source of vitamin D and iron," says Antonette Hardie, a registered dietician at The Ohio State University Wexner Medical Center.

Plus, you can absorb vitamin D from sunlight — but this has its limitations. "If you're mostly indoors or outside with clothes on, it can be helpful to supplement. This is particularly true during the wintertime when daylight hours are brief," Andrews says.

Adults need 500 micrograms or 600 international units (IU) each day, according to the ODS.​ If you have a vitamin D deficiency, your needs may be higher in order to build reserves of the vitamin — check with your doctor to be sure.

To get omega-3 fatty acids, you'll need to eat foods or take supplements that contain them, per the ODS. Your body can't produce them on its own. And having omega-3s is important, as they support a healthy heart and brain, per the American Heart Association (AHA).

Foods rich in omega-3s include many types of seafood, but there are also vegetarian sources, including nuts, seed, plant oils and fortified foods, according to the ODS.

Vegetarians who want to up their omega-3s won't be able to turn to fish oil, a common supplement for this nutrient. Instead, opt for a supplement with algae oil, per the ODS.

There isn't a general guideline for how much omega-3 you need.

But there is a recommendation when it comes to alpha-linolenic acid (ALA), which is one of the three main acids in omega-3s, per the ODS. For ALA, the recommendation is for adults assigned female at birth to take in 1.1 grams of ALA per day. Adults assigned male at birth should get 1.6 grams a day, according to the ODS.

If you follow a vegetarian diet and have a deficiency in any of these vitamins, supplements could help, Hardie says. But before you pick up a bottle, consider these suggestions:

If you're a vegetarian, you may suspect you need a supplement, but you should always talk to your doctor or dietitian before adding one to your routine.

"Be sure to check with your primary care doctor before starting new supplements. You want to make sure it doesn't interact with any other vitamins or medications you take," Hardie says.

Your doctor might recommend you get a blood test done, too. "You won't know for sure if you're deficient or low in any vitamin without getting blood work done," Hardie says. Results from your blood test will indicate exactly how deficient you are, in which case your doctor will be better able to dictate how much of a supplement you should be taking, and for how long.

One thing that makes purchasing supplements challenging is that it's a largely unregulated market. The FDA does not check that supplement products meet safety standards prior, and manufacturers are often able to make bold — sometimes unsubstantiated — claims on the packaging.

Look for options that have a stamp of approval from GMP, USP, NSF or other third-party organizations that test supplements. "This suggests that the manufacturer has quality control measures in place," Andrews says.

If you're diligently adhering to a meat-free diet, the last thing you'll want to do is ingest an animal product in pill form. But along with checking the ingredient for fish or meat additives, you'll also want to make sure the supplement does not contain anything you're allergic to, such as soy or wheat.

While a vitamin can be beneficial if you have dietary restrictions, more isn't always better. Many vitamins have upper limits — aka, the max amount you should take in per day. For example, the upper limit for iron is 45 milligrams for adults, per the ODS. Taking more than that can be harmful and cause serious side effects.