I often get the question, “Should I take a multivitamin?” The answer is, it depends! It’s best to only take a vitamin or mineral supplement if you have a known deficiency. You can get tested at your doctor to see if you are deficient, and get recommendations on if you need to take anything, what to take, what form to take it in, and how much to take. Taking a vitamin or mineral supplement as “insurance” or “just in case” is not recommended. At best, it can result in wasted money and really “expensive pee,” because your body will just excrete out water-soluble vitamins it doesn’t need. At worst, you could end up with a toxicity or negative health outcomes.
Also consider if someone is recommending that you take a supplement, vitamin, or mineral—do they have an incentive for you to take it? Are they selling it? Or do they get a percentage of the sale? If so, don’t do it. If you truly need a supplement, you can get it from neutral third-parties. Multi-level marketing often sells questionable products and there is nothing you can only get from MLM that you couldn’t get at a normal store that you would actually NEED.
Also be sure your supplement is clean from contaminants by looking for the NSF Certified for Sport, Informed Choice, or USP labels.
Micronutrients do not provide energy but play an important role in health and the way your body functions. There are many micronutrients, but we picked out the most common ones and made this reference chart for you. Keep in mind, it doesn’t list every single function, nor every single food source (that would be impossible!).
Recommended intake is set for most adults age 18 and up based on guidelines from the United States. You may need a different amount based on your health history. Always check with your doctor before taking any vitamin, mineral, or supplement.
| Micronutrient | What it does | Food sources | Recommended intake per day | Implications for sports performance |
| Iron | Carries oxygen to tissues, helps with metabolism and cell function | Meat, seafood, nuts, beans, dark leafy vegetables, fortified cereals and breads | Males 8 mg, Females 18 mg | If deficient, may feel weak, fatigued |
| Calcium | Bone health and strength, nerve conduction, enzyme and hormone function, muscle contraction | Dairy products, fish with edible bones (sardines), kale, broccoli, fortified soy and cereal products | 1000 mg, | Supports bone health and may help prevent injury |
| Zinc | Helps with numerous cell functions, immunity, growth in children | Fortified cereals, meat, poultry, beans, nuts, seafood, dairy products | Males 8 mg, Females 11 mg | Is lost in sweat; needs to be replaced with diet after heavy sweating |
| Magnesium | Enzyme reactions, muscle contraction, blood pressure regulation, bone health | Meat, poultry, eggs, fruit, leafy green vegetables, fortified cereals | Males 420 mg, Females 320 mg | Is lost in sweat; needs to be replaced with diet after heavy sweating. If deficient, may affect ability to metabolize food for energy in the cell. |
| Potassium | Heart beat, nerve conduction, blood pressure regulation | Meat, milk, fruits, vegetables, legumes, whole grains | 4.7 g | Is lost in sweat; needs to be replaced with diet after heavy sweating. If low, affects heart rate. |
| Vitamin A | Immunity, vision, eye health, skin health, bone growth | Liver, milk, eggs, leafy vegetables, carrots, sweet potatoes, broccoli, squash, cantaloupe | Males 900 mcg Retinal Activity Equivalents (RAE), Females 700 mcg RAE | May help with skin healing when wounded. |
| Vitamin E | Antioxidant, immunity, cell function | Vegetable oils, nuts, spinach, broccoli, fortified foods (often used as a preservative) | 15 mg | None known |
| Vitamin D | Nerve function, muscle function, bone health, immunity | Fortified foods, fatty fish, egg yolks, mushrooms. Also synthesized in your skin when in the sun | 15 mcg | Adequate status may help with muscle contraction, mood, and bone health |
| Vitamin K | Blood clotting, bone health | Green leafy vegetables, vegetable oil, meat, cheese, eggs, soybeans | Males 120 mcg, Females 90 mcg | None known |
| Vitamin C | Antioxidant, iron absorption, immunity, skin health | Citrus fruits, bell peppers, kiwi, broccoli, berries, potatoes, tomatoes, cantaloupe | Males 90 mg, Females 75 mg | May help with wound healing. May help reduce or prevent respiratory tract infections in a physiologically stressed athlete. |
| Vitamin B 6 | Enzyme reactions, metabolism, immunity, fetal brain development | Poultry, fish, potatoes, fruit, legumes, soy products, bananas, watermelon | 1.3 mg | None known. |
| Vitamin B 12 | Nerve and cell function, DNA production | Liver, clams, fish, meat, poultry, nutritional yeast, fortified cereal | 2.4 mcg | None known. |
| Riboflavin | Cell function, energy metabolism | Eggs, meat, milk, asparagus, broccoli, spinach, fortified cereal | Males 1.3 mg, Females 1.1 mg | None known. |
| Thiamine | Energy metabolism, nerve function | Meat, fish, pork, whole grains, fortified cereal | Males 1.2 mg, Females 1.1 mg | None known. |
| Niacin | Energy metabolism, cell function | Meat, fish, poultry, nuts, legumes, whole grains, fortified cereal | Males 16 mg Niacin Equivalents (NE), Females 14 mg NE | None known. |
| Biotin | Energy metabolism, skin/hair/nail health | Meat, fish, eggs, nuts and seeds, sweet potatoes, spinach, broccoli | 30 mcg | None known. |
| Folate | Cell metabolism, DNA production | Liver, fortified cereal, leafy green vegetables, fruit, nuts, legumes, peas | 400 mcg | None known. |
Want to learn more? Check out our on-demand masterclass Nutrition for Climbers, or our book Nutrition for Climbers: Fuel for the Send.