Vitamin D provides a host of benefits—it builds strong bones, assists with protein synthesis and improves immune response, among other things. Surprisingly, the majority of athletes are deficient in this essential vitamin. Deficiencies can cause decreased bone density, muscle weakness, reduced immune system function and respiratory problems.

Although it can be produced via absorption of ultraviolet rays from the sun, the main cause of those deficiencies stems from poor nutrition. Here are some recommendations on how to get more of this important vitamin to improve your performance.

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Sunlight

Our bodies actually produce vitamin D when our skin is exposed to the sun’s ultraviolet rays, specifically ultraviolet B (UVB) radiation. When UVB rays hit the skin, a chemical reaction occurs, beginning the process that converts prohormones in the skin into this essential vitamin. Translation: get out and train in the sunlight.

Supplementation

It can be difficult for athletes to get their recommended daily amount of vitamin D from food alone, so many dietitians recommend taking a supplement. Choose a supplement that provides 400 to 600 IU of vitamin D. Dietitians also suggest taking the supplement with your largest meal to increase its absorption into your body. However, many people are also deficient in magnesium, which plays an important role in how your body activates vitamin D. Therefore, pairing your vitamin D supplement with a magnesium supplement can be a good idea.

Food

It is always best for athletes to get the recommended amount of vitamin D from the food they eat. Here are some healthy foods high in vitamin D.

Fish Canned

1. Salmon (4 oz): 520 IU
2. Sardines (4 oz): 304.8 IU
3. Tuna (4 oz): 205.33 IU

Vegetables

1. Spinach (1 cup): 31 IU
2. Mushrooms (1 cup): 634 IU
3. Sweet Potatoes (1 cup): 41 IU

Fruits

1. Fortified Orange Juice (1 cup): 137 IU

Grains/Beans

1. Tofu (4 oz): 106.67 IU
2. Oats (1 cup): 150 IU
3. Bran Fortified Cereal (1 cup): 174 IU

Dairy

1. Egg Yolks (1 egg): 41 IU
2. 2% Milk (1 cup): 124 IU
3. Greek Yogurt (6 oz): 80 IU
4. 2% American Cheese(1 slice): 85 IU

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