Vitamins & Minerals
Vitamins and minerals are nutrients necessary to sustain human life. Some are needed in minuscule amounts and others are necessary in larger amounts and amounts needed vary during a person’s lifespan.
Vitamins A, D, E and K are fat-soluble and can be stored in the body. Betacarotene – a precursor of vitamin A found in foods with red, yellow and orange pigment like carrots, sweet potato, and cantaloupe – is converted to vitamin A in the body. B vitamins include B1 (thiamine), B2(riboflavin), B3 (niacin), B6, folic acid and B12. Vitamin C is another water-soluble vitamin. These vitamins are not stored in the body but are flushed out in the urine.
Vitamins are required in the diet for many important reasons, such as to prevent certain diseases, such as rickets, anemia, scurvy, xeropthalmia, (an eye condition leading to blindness), to allow blood to clot, to extract energy from food, to contribute to bone metabolism and to maintain epithelial integrity.
Minerals include calcium, phosphorus, sodium, potassium, magnesium, manganese, sulfur, chloride, iron, iodine, fluoride, zinc, copper, selenium, chromium and cobalt (which is part of the vitamin B12/cobalamine).
Minerals are found in blood, bones, tissues and in the case of some, such as iron, in every living cell. They carry oxygen and carbon dioxide, and are part of DNA and RNA; they are a necessary component of metabolism, like vitamins. They also help maintain acid base balance, are part of bones and teeth, are required for normal growth, are part of glands, and are needed for the heart to pump normally. They also are needed to prevent certain diseases.
In addition, some vitamins and minerals have antioxidant properties, which work to prevent oxidation in the body, lowering the risk of cancers and inflammation. Eating a good diet supplies all of these vitamins and minerals, but strict vegetarians must take a supplemental intake in a pill form. Good foods include seafood, dark green leafy vegetables (such as kale, spinach and chard), citrus fruits, unrefined grains, such as whole wheat or oat cereals and bread, brown rice, eggs, milk, yogurt, cheese, nuts, legumes, root vegetables (such as potatoes, but not highly processed potatoes, like chips) and a variety of other fruits and vegetables.
Multivitamins and minerals are available to purchase over the counter, but they should not be considered a substitute for choosing as good a diet as possible. The American diet can be low in calcium, iron and vitamin D. Americans living in the less sunny parts of the U.S. will not be able to make vitamin D from sunshine in the winter months. Although it can be stored in the body, it is a good idea to pay attention to eating more foods with vitamin D and allowing skin to be exposed to sunlight in the summer months. Few foods have large amounts of vitamin D. Some fish, such as mackerel, sardines and salmon contain vitamin D. Milk is fortified with vitamin D and so are foods such as yogurt made from fortified milk.
To find out how much vitamin and mineral intake is recommended for your age group and gender, the United States Recommended Dietary Allowances is published on the USDA website.
Kathryn D. Clark, M.S.Â Registered dietician, retired
Updated October 2022