Vitamin and Mineral Supplementation for a Whole-Food Plant-Based Diet

Citrus fruit with supplements on a white plate​You have no doubt read or been told a common misconception that you’ll need a variety of dietary supplements to ensure you won’t “waste away” on a plant-based diet! Okay, I’m being dramatic here – hopefully, you haven’t received that reaction; however, friends, family members, and/or healthcare professionals who may not understand the benefits of a plant-based approach may be reluctant to support you following a plant-based diet for fear you will be unable to meet your nutritional needs. To ensure their nutritional needs are being met, some will turn to dietary supplements. Take a walk into your local health food store and there are seemingly infinite supplements to choose from, not to mention a plethora of brand names. How does one choose?

More importantly, are they truly necessary? Are they safe?

From a range of micro and macronutrients, fiber, and a long list of highly protective phytonutrients (compounds that protect us from diseases like cancer and heart disease), not only are plant-based diets unbelievably nutrient-dense, they’re super colorful and flavorful, too! Below is a list of nutrients thought to be hard for plant-based eaters to obtain in sufficient amounts. Let’s go through these and determine whether one actually needs to supplement or not.

What you’ll need…

Vitamin B-12

B-12 is naturally made by bacterial organisms found in soil and in the digestive tract of animals. The bacteria present in a human digestive tract can also produce B-12, but it is such a small amount that it won’t meet nutritional requirements. Adults require 2.4 micrograms (mcg) of B-12 per day. Plant sources of B-12, such as chlorella algae and fermented foods, are not considered reliable sources for plant-based diets; reliable plant sources of B-12 are only found in fortified foods and supplements. The amount of B-12 in fortified foods varies greatly depending on the product and the brand name. For example, fortified almond milk might contain 3 mcg of B-12 while another brand of soymilk may only contain 1.5 mcg. Be sure to read the nutrition facts label to find the amount added per serving.

It should be noted, that B-12 deficiency can affect those who eat animal products, too, particularly older adults and those taking certain medications that inhibit proper B-12 absorption.

Take Away: Supplementation of this nutrient is non-negotiable while following any version of a plant-based diet. Those who consume animal products in their diet might need supplementation, but this would be an individualized recommendation determined by your doctor.

What you might need…

Essential Fatty Acids – EPA and DHA

Research has shown the increasingly important role of two omega-3 fats: EPA and DHA. EPA and DHA are important for brain & eye health, cell membranes, and important during pregnancy. The richest sources of EPA and DHA are found in seafood; however, this is because they have a diet rich in algae. Humans can turn a small amount of dietary ALA (from soy, walnuts, chia seeds, hemp seeds and/or flaxseed) into EPA and DHA, which, according to the Academy of Nutrition and Dietetics position paper on Vegetarian Diets, is sufficient for healthy individuals and those without an increased need.

Take Away: Although a recommended amount of EPA and DHA has not been established, individuals on a plant-based diet may want to consider supplementing with an algae-based omega-3 that contains these nutrients.


Even though many have grown up to think dairy is the best or only source of calcium, adequate calcium intake can be obtained in a well-planned WFPB diet. The trick is becoming familiar with the quantity of calcium per serving in your favorite plant foods and how well those foods can be absorbed in the body.

It’s easier than it sounds, really!

Oxalates are a compound found in plant foods that can decrease the amount of calcium our body is able to absorb from plant sources. The more oxalate in a plant, the less calcium we can absorb. High oxalate, high calcium foods include greens such as spinach and Swiss chard. You should still include these in your diet for many other reasons, but don’t rely on them for your main source of calcium. Use these other low oxalate, high-calcium plant options to keep your bones strong: kale, Chinese cabbage, bok choy, tofu made with calcium, tahini, almonds, white beans and figs. Calcium-fortified foods are also an option. Adults need 1,000-1,200 mg per day depending on age. One cup of firm tofu (made with calcium sulfate) contains 506 mg!

Take Away: It is 100% possible to meet your calcium needs through plant foods, but if you are still learning to like some of the calcium-rich leafy greens or can’t seem to eat large enough portions, talk with your doctor and a registered dietitian to see if a low-dose calcium supplement is necessary.

Vitamin D

Low levels of vitamin D in people are becoming more and more prevalent and the problem is not exclusive to those who follow a plant-based diet. Sunlight is the easiest way for us to obtain this nutrient, but some plant-based food sources include fortified foods, fortified juice & non-dairy milks, fortified cereal, and mushrooms that have been grown under ultraviolet light. The amount of vitamin D in fortified foods varies greatly depending on the product and the brand name. Be sure to read the nutrition facts label to find out the amount per serving.

Take Away: If you can’t get enough sunlight (if you live in areas with a limited number of sunny days per year) and/or fortified foods, a supplement might be needed. Talk with your doctor about monitoring the vitamin D levels in your blood.


Depending on age and gender, iron requirements range from 8-18 mg per day. There has been a long-held belief that plant-based eaters will become deficient because plant sources of iron (non-heme iron) are poorly absorbed compared to iron found in animal products (heme iron). A review of the research indicates iron from plant sources absorbs as well as animal sources. Absorption of plant sources of iron is influenced by how much a person has stored in their body (when someone has low stores, the body is better at absorbing the non-heme iron) and other foods in the meal. Eating foods rich in Vitamin C, like bell peppers or lemon juice, with foods high in non-heme iron will enhance absorption. Using cast iron cookware will add iron to the meal, too. Also, make sure to eat your beans or lentils on a daily basis! One cup of cooked lentils contains about 6 mg of iron and don’t forget to add a hit of Vitamin C to the meal, too.

Take Away: When eating a well-planned WFPB diet it is possible to meet iron needs. However, certain individuals, such as women with heavy menstrual cycles and pregnant women, may need to supplement based on individual circumstances.


This mineral is essential for healthy thyroid function and is found mainly in iodized salt, fish, dairy and sea vegetables such as seaweed and kelp. Inadequate intakes of iodine may be a concern across the board, not just for those following a plant-based diet. As more people have steered away from cooking with iodized salt in favor of other types of salt and many processed foods do not use iodized salt, iodine intake may be inadequate in the American diet. Adults need 150 micrograms (mcg) of iodine per day. Plant-based eaters can meet that need by including a variety of iodine-containing plant foods in their daily meal plan: ¼ teaspoon iodized salt contains 75 mcg, 1 package of roasted seaweed snacks has about 25 mcg, ½ cup navy beans contains 32 mcg and 1 medium baked potato (with skin) has about 60 mcg.

Take Away: Unless instructed to do so by your doctor, you do not need to supplement with iodine. Instead, it would be prudent for WFPB eaters to include iodized salt or a combination of potatoes and white beans in the diet to meet their needs.

What you can get plenty of on a plant-based diet (but are often told you won’t)…

Essential Fatty Acids – ALA and LA

Whether you are plant-based or include animal products in your diet, alpha-linolenic acid (ALA), an omega-3 fat and linolenic acid (LA), an omega-6 fat, are two essential fatty acids that must be obtained through food because our body can’t make them. Adult females need 1.1 grams ALA and 12 grams LA; adult males need 1.6 grams ALA and 17 grams LA per day. Supplementation is not needed since these are easy to obtain on a WFPB diet. Consuming adequate amounts of soy, walnuts, chia seeds, hemp seeds and/or flaxseed will ensure you’re meeting your ALA and LA needs. Just 1 tablespoon of ground flaxseed will meet (or exceed) your daily need with 1.6 grams ALA!

The overall ratio, or balance, of these two essential fatty acids in the diet is important as well. When ALA is consumed, its omega-3 fat has anti-inflammatory effects in the body; however, LA an omega-6 fat, has a pro-inflammatory effect. We need some omega-6 fat in our diet because they serve various functions in our body, but the typical Western diet contains far too much. Vegetable oils used during cooking and added to packaged foods (including most prepared sauces, dressings, crackers, chips, and oil-roasted nuts or seeds), are high in omega-6. Too much omega-6 is thought to be one of the major reasons why inflammatory conditions like obesity, diabetes, and heart disease are on the rise. By increasing our intake of whole plant foods that are rich in omega-3 like walnuts, chia, flax, and hemp and keeping our intake of refined vegetable oils low (or no added oils), we will have the proper balance.

Take Away: When eating sufficient amounts and in the correct ratio it is very easy to meet our essential fat needs with a WFPB diet.

Final Thoughts…

A well-planned plant-based diet can meet a person’s nutritional needs! With the exception of B-12, supplementing with vitamins is not as critical as once thought – if the person is eating sufficient quantities of foods containing “nutrients of concern” and a diversity of plant-based foods. It is always preferred that we obtain nutrients from whole foods rather than a supplemental form because it’s possible to get too much of a good thing – supplements can put us at risk for that. Furthermore, there can be concerns about the safety of dietary supplements related to contamination or product dosage. With that said, there are certain supplements that are needed and some that might be needed depending on individual circumstances. This need will depend on many factors and you should always talk with your health care provider to determine what your individual need is.

Learn more in Part 3 of this series: Transform Your Health with a Plant-Powered Plate – Macronutrients!

Missed Part 1? Check it out here: Part 1 – Transform Your Health with a Plant-Powered Plate: The Basics

Christina Archer is a registered dietitian with a master’s degree in Nutritional Science, board certification in Integrative and Functional Nutrition through the Integrative and Functional Nutrition Academy and currently works for Sansum Clinic where she provides individualized medical nutrition therapy as well as nutrition and lifestyle recommendations to optimize health.


Melina, Vesanto, et al. Position of the Academy of Nutrition and Dietetics: Vegetarian Diets. Journal of the Academy of Nutrition and Dietetics, 2016; 116 (12):1970–1980., doi:10.1016/j.jand.2016.09.025.

Palmer, Sharon. Nutrients of Concern for Individuals Following a Plant-based Diet. Today’s Dietitian, 2014 June 2014; 2–8.

U.S. Department of Health and Human Services and U.S. Department of Agriculture. 2015–2020 Dietary Guidelines for Americans. 8th Edition. 2015 December. Available at

Higdon J. Essential Fatty Acids. Linus Pauling Institute. 2003. Reviewed 2019 June. Accessed June 2020:

U.S. Department of Agriculture. Agricultural Research Service. FoodData Central. 2019. Accessed June 13, 2020.

Higdon, J. Vitamin B12. Linus Pauling Institute. 2000. Reviewed 2014 April. Accessed June 2020.

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