Vitamin & Mineral Supplementation

I recommend taking a multivitamin/mineral supplement, such as Centrum, on a daily basis. For most people, this is not likely to cause any change or improvement in health. But I’d like to discuss why I recommend a supplement anyway.

U.S. survey data show that about 30% of the population has at least one vitamin deficiency or anemia. Risk of deficiency is higher in groups with lower income and lower dietary quality. Prevalences of deficiency for iron, Vitamin B12, C, B6, or D are about 5-10%, while prevalences for other vitamin deficiencies are around 1%.

There are particular groups who will benefit more from supplementation. People with depression often have poor appetite, low motivation, isolation, reduced shopping and cooking, and neglect of self-care. Poverty and food insecurity worsen diet quality. Northern winters and indoor life worsen vitamin D status. Many people wisely avoid sun exposure to improve skin health, but this practice also reduces Vitamin D levels. Alcohol use is associated with inadequate thiamine, folate, and other nutrients. Vegan diets require B12 attention. Bariatric surgery and inflammatory bowel disease can alter absorption.

While almost all large studies of vitamin/mineral supplementation in the general adult population have shown no significant benefit, the recent COSMOS cognition findings in older adults are a very important exception. In that 2024 study, daily multivitamin/mineral supplementation showed a modest benefit for global cognition and episodic memory in adults aged 60 and older. The authors estimated the global cognition effect as roughly equivalent to reducing cognitive aging by about two years, with the effect size around 0.1 standard deviation units.

By way of analogy, let’s consider adult height or weight. A 0.1 standard deviation difference corresponds to a difference in adult height of about 1 cm (half an inch), or a difference in weight of about 2 kg (4 pounds). So the effect of supplementation on cognition is very small, but just enough to be noticeable and significant.

The history of deficiency disease is a reminder that small molecules can have large consequences: scurvy in sailors deprived of fresh produce; beriberi associated with thiamine deficiency and polished rice; pellagra associated with niacin deficiency and poverty; rickets in children deprived of sunlight and vitamin D; Wernicke-Korsakoff syndrome in severe alcohol-related malnutrition; iodine deficiency causing goitre and severe developmental abnormalities; iron deficiency causing fatigue and anemia; B12 deficiency causing neuropathy and cognitive symptoms. It should be noted that a daily supplement is insufficient to treat these severe deficiency diseases—these can be medical emergencies and need professional interventions.

Excess states are important too. Vitamin A toxicity, iron overload, B6 neuropathy, hypercalcemia from excessive vitamin D, copper deficiency from excessive zinc, and iodine-related thyroid disturbance remind us that “natural” does not mean harmless. Oxygen, water, iron, and sunlight are all natural; too little or too much can injure you.

So there is enough of an evidence base to justify daily multivitamin/mineral supplementation with a standard commercial product. One should choose products containing amounts of each ingredient that are similar to the daily Recommended Daily Allowance (RDA) or “Daily Value,” and avoid products that claim to have “megadoses” as this could lead to toxicity.

In the next posts, I’m going to discuss individual vitamins and minerals separately, because some may have slight beneficial effects as augmentations to help treat mental health problems, and I think they are not emphasized enough in modern psychiatry, especially given the very low risk of side effects or toxicity with standard doses.


Annotated bibliography

Vyas, C. M., Manson, J. E., Sesso, H. D., Cook, N. R., Rist, P. M., Weinberg, A., Moorthy, M. V., Baker, L. D., Espeland, M. A., Yeung, L.-K., Brickman, A. M., & Okereke, O. I. (2024). Effect of multivitamin-mineral supplementation versus placebo on cognitive function: Results from the clinic subcohort of the COcoa Supplement and Multivitamin Outcomes Study (COSMOS) randomized clinical trial and meta-analysis of 3 cognitive studies within COSMOS. The American Journal of Clinical Nutrition, 119(3), 692–701. https://doi.org/10.1016/j.ajcnut.2023.12.011

This is the key paper showing modest cognitive benefits resulting from multivitamin-mineral supplementation in older adults.



Bird, J. K., Murphy, R. A., Ciappio, E. D., & McBurney, M. I. (2017). Risk of deficiency in multiple concurrent micronutrients in children and adults in the United States. Nutrients, 9(7), Article 655. https://doi.org/10.3390/nu9070655

An estimate of the risk of micronutrient deficiency in the U.S. population. The paper reports that about 31% of the U.S. population was at risk of at least one vitamin deficiency or anemia, with higher risk in women, low-income households, people without a high-school diploma, and underweight or obese individuals.



O’Connor, E. A., Evans, C. V., Ivlev, I., Rushkin, M. C., Thomas, R. G., Martin, A., & Lin, J. S. (2022). Vitamin and mineral supplements for the primary prevention of cardiovascular disease and cancer: Updated evidence report and systematic review for the US Preventive Services Task Force. JAMA, 327(23), 2334–2347. https://doi.org/10.1001/jama.2021.15650

The evidence shows that supplementation in generally healthy adults without known deficiencies produces little or no benefit in preventing cardiovascular disease, cancer, or death, with the exception of a small and limited finding for cancer incidence with multivitamin use. Beta-carotene was associated with increased lung cancer risk in higher-risk groups.



Blampied, M., Tylianakis, J. M., Bell, C., Gilbert, C., & Rucklidge, J. J. (2023). Efficacy and safety of a vitamin-mineral intervention for symptoms of anxiety and depression in adults: A randomised placebo-controlled trial “NoMAD.” Journal of Affective Disorders, 339, 954–964. https://doi.org/10.1016/j.jad.2023.05.077

While supplements overall did not perform better than placebo in terms of endpoint response rates, there was some evidence that depression and anxiety symptoms improved more quickly in the micronutrient group.



Loftfield, E., O’Connell, C. P., Abnet, C. C., Graubard, B. I., Liao, L. M., Beane Freeman, L. E., Hofmann, J. N., Freedman, N. D., & Sinha, R. (2024). Multivitamin use and mortality risk in 3 prospective US cohorts. JAMA Network Open, 7(6), Article e2418729. https://doi.org/10.1001/jamanetworkopen.2024.18729

This cohort study of almost 400 000 healthy adults over more than 20 years of follow-up, found no lower risk of all-cause mortality among daily multivitamin users in three large prospective U.S. cohorts. It also found no mortality advantage for heart disease, cancer, or cerebrovascular disease.