4. Which food has the most magnesium?
Answer: One ounce of almonds has the most, with 80 milligrams. A potato is second, with 48 milligrams. Next is the banana, at 32 milligrams, and finally the raisins, at 26 milligrams.
Daily Need: Men should get 400 to 420 milligrams and women 310 to 320 milligrams daily.
Why It Matters: Magnesium helps maintain normal muscle and nerve function, keeps heart rhythm steady, supports a healthy immune system and keeps bones strong. Magnesium also helps regulate blood sugar levels, promotes normal blood pressure and is involved in energy metabolism and protein synthesis.
5. Which food has the most calcium?
Answer: Collards are the highest, at 266 milligrams, then the spinach, at 245 milligrams, broccoli, at 106 milligrams, and kale, at 94 milligrams.
Daily Need: Men and women ages 19 to 50 need 1,000 milligrams per day, and people ages 51 and up need 1,200 milligrams.
Why It Matters: Calcium is famous for building and maintaining strong bones, but it also plays a role in blood clotting, blood pressure regulation and muscle and nerve functioning. Inadequate calcium can result in bone deformities, muscle cramps, hypertension and osteoporosis, which is characterized by fragile bones and increased risk of bone fractures.
More: Avoiding Nutrient Deficiencies
6. Which food has the most vitamin D?
Answer: Believe it or not, milk has little or no vitamin D—5 IU (international units) per cup. The shiitake mushrooms have about 45 IU and the egg has 27 IU, but the sockeye salmon has the most, at 447 IU—keep in mind that only sockeye salmon has vitamin D.
Daily Need: Men and women ages 14 through 70 need about 600 IU or 15 micrograms (mcg) per day. Also, see: www.ajcn.org/content/88/2/570S.full
Why It Matters: Vitamin D is unique in that it's found in food but can also be made in your body after exposure to ultraviolet (UV) rays from sunlight. The major biologic function of vitamin D is to maintain normal blood levels of calcium and phosphorus. By promoting calcium absorption, vitamin D helps to form and maintain strong bones. It also works in concert with a number of other vitamins, minerals and hormones to promote bone mineralization. Vitamin D is associated with decreased occurrence of fractures when taken with calcium. It was previously thought that many of us were not getting enough vitamin D; however, recent research has not supported that notion. Typically, 15 minutes in the sunlight will be just fine, but during the winter months (or if you don't get out much), you should consider food sources (not supplements, unless a physician advises you to do so).
More: Vitamin 101 for Runners
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