The mineral magnesium is important for every organ in the
body, particularly the heart, muscles, and kidneys. It also
contributes to the composition of teeth and bones. Most
importantly, magnesium activates enzymes, contributes to
energy production, and helps regulate calcium levels as well
as copper, zinc, potassium, vitamin D, and other important
nutrients in the body.
Rich sources of magnesium include tofu, legumes, whole
grains, green leafy vegetables, wheat bran, Brazil nuts,
soybean flour, almonds, cashews, blackstrap molasses,
pumpkin and squash seeds, pine nuts, and black walnuts.
Other good dietary sources of this mineral include peanuts,
whole wheat flour, oat flour, beet greens, spinach,
pistachio nuts, shredded wheat, bran cereals, oatmeal,
bananas, and baked potatoes (with skin), chocolate, and
deficiencies in developed countries are rare because table
salt is supplemented with iodine and crops in developed
countries are generally grown in iodine-rich soil. A
deficiency of iodine can lead to hypothyroidism (low thyroid
hormone levels); symptoms of this condition include
sluggishness, weight gain, and sensitivity to temperature
changes. In infants and children, hypothyroidism can impair
physical and mental development.