Magnesium is vital to both hard and soft body tissues. It is essential for metabo-lism and regulates nerve and muscle function, including the heart, and plays a role in the blood-clotting process.
Sources.Like phosphorus, magnesium is widely distributed in foods, butit is found primarily in plant foods. The nutrient-dense foods are green leafy vegetables, legumes, nuts, whole grains, and some fruits such as avocados and bananas. Milk is also a good source if taken in sufficient quantity. For example, 2 cups of fat-free milk provide about 60 mg of magnesium.
Magnesium is lost during commercial food processing and in cooking water, so it is preferable to eat vegetables and fruits raw rather than cooked.
Requirements.The requirement for magnesium is provided as AIs(Table 8-6). Magnesium is measured in milligrams.
Deficiency.Because of the wide availability of magnesium, its deficiencyamong people on normal diets is unknown. When deficiency was experimen-tally induced, the symptoms included nausea and mental, emotional, and muscular disorders.