The essential minerals magnesium and selenium are often overlooked. Magnesium is vital for enzyme activity and energy production, and assists in nerve transmission. A deficiency can result in irritability, nervousness, depression, muscle weakness and worsened premenstrual syndrome. Selenium works as an antioxidant, protects the immune system by aiding in antibody production and helps maintain a healthy heart and liver. Selenium and magnesium can be taken as supplements, but are also available in many foods. The recommended daily intake is 320 to 420 milligrams for magnesium and 55 micrograms for selenium. As with all supplements, consult your doctor before beginning a dietary regimen with added magnesium and selenium.
Nuts and Grains
Nuts and grains may be the best dietary sources of magnesium and selenium. Peanuts and pumpkin seeds are particularly high in magnesium, with about 50 milligram per serving. Brazil nuts are especially high in selenium, containing 544 micrograms, and other tree nuts such as almonds and cashews have high amounts of both selenium and magnesium. Whole grains such as wheat and oats are also high in both minerals, with up to 160 milligrams magnesium and 60 micrograms selenium per serving. The mineral levels in the foods may vary depending upon mineral levels of the soil where the grain was raised. This is particularly true for selenium, which is deficient in areas such as the Ozark Mountains and places like New Zealand.
Animal protein products such as meat, fish and dairy are known to be high in selenium and magnesium. Herring, salmon and tuna and other fish may contain up to 60 micrograms selenium and 90 milligrams of magnesium per serving. Beef is particularly high in both minerals, with up to 50 micrograms selenium and 50 milligrams of magnesium, depending on serving size. Lamb, pork and dark meat poultry have lower amounts. Dairy products like cheese and yogurt are high in both minerals. Nondairy milks such as soy have up to 25 milligrams of magnesium per serving.
Green beans, lima beans and peas have as much as 180 milligrams of magnesium and 20 micrograms of selenium per serving. Other vegetables, like asparagus and Brussels sprouts, along with mushrooms, have 5 to 10 micrograms of selenium per serving, while vegetables such as artichokes, okra and leafy salad vegetables like Swiss chard have high levels of magnesium, with 50 to 60 milligrams per serving.
Most fruits are not high in selenium, but bananas, dates and pomegranates have the highest levels, and may contain up to 5 micrograms per serving. These fruits and others, such as blackberries, currants and raspberries, have up to 50 milligrams of magnesium per serving, depending upon the area where the fruit was grown.