How do I know if micronutrients might be beneficial for me?

If you are healthy and eat a well-balanced, diverse diet, chances are you don’t need a micronutrient supplement. However, in special cases, micronutrient supplementation could make sense. People with deficiencies often benefit more from micronutrient supplementation. For example, vitamin D supplementation is most beneficial for people with low baseline levels.^[1] However, people with sufficient baseline levels showed only a slight risk reduction for acute respiratory infection. Another example is high-performing athletes, especially during periods of intensified training and/or competition. A Cochrane review^[2] showed that marathon runners, skiers, and soldiers performing subarctic exercises showed a substantial risk reduction (RR 0.48) of getting a cold when supplementing vitamin C. If you are a high-performing athlete, this could make a practical difference to your performance.

In general, beware of toxic overdosing and the potential side effects when supplementing minerals such as zinc^[3] and water-insoluble vitamins such as vitamin D^[4]. Overall, the usefulness of micronutrient supplementation most often requires individual consideration. Hence, it’s difficult to make any generalized recommendations.