Thursday, January 31, 2008

Dietary Consideration: Vitamins & Minerals

Dietary Recommendations: Vitamins

Vitamins in the amounts equal to the RDAs should be included in the diet each day.

Dietary Implementation: Vitamins

A diet containing the food servings recommended for carbohydrates, proteins, and fats will more than meet the RDA standards.

Extra servings of green and yellow vegetables, citrus and other fruits, and other nonanimal food sources high in fiber, vitamins, and minerals is a wise substitute for high-fat foods.

Those who eat a sound diet as described in this chapter do not need a vitamin supplement. Those who insist on taking a daily vitamin supplement are advised not to take daily amounts larger than the RDA and only after following the guidelines for dietary supplements suggested later in this concept.

Adequate mineral intake is necessary for good health, but excessive mineral intake is NOT necessary and can be harmful to health.

Diet Start

Like vitamins, minerals have no calories and provide no energy for the body. They are important in regulating various bodily functions. Two of the ten key nutrients, calcium and iron, are minerals. Calcium is important to bone, muscle, nerve, and blood development and function. Iron is necessary for the blood to carry adequate oxygen. Other important minerals are phosphorus, which builds teeth and bones; sodium, which regulates water in the body; zinc, which aids in the healing process; and potassium, which is necessary for proper muscle function.

RDAs for minerals are established to determine the amounts of each necessary for healthy day-to-day functioning. Recently the National Research Council made slight adjustments in the RDAs. There is evidence that lower than recommended daily intake of calcium is associated with a higher than normal incidence of bone fractures among adults. However, the value of an intake of calcium greater than the RDA in the prevention of osteoporosis has yet to be clearly established. There is limited evidence of an association between high calcium intake and high blood pressure. A few long-term studies have suggested that high calcium intake is associated with a lower incidence of colon cancer, but to date the evidence is considered preliminary and inconclusive. Fluoride is a mineral often added to water supplies. There is clear evidence that fluoridation of public water systems reduces the incidence of dental caries.

Salt is another dietary mineral. There is strong evidence that excess table salt (sodium chloride) is associated with high blood pressure. People who consume excess salt have an increase in blood pressure with age that is much greater than for those who do not consume excess amounts of salt. Further, once high blood pressure develops it cannot be fully reversed by salt restriction though reduction in salt in the diet is effective in some reduction in blood pressure. Adults over fifty-five and blacks are especially susceptible to hypertension. Intake of adequate potassium in the diet combined with low sodium intake seems to be important in the prevention of hypertension. Excess salt from consumption of salt-cured foods has been associated with some gastrointestinal problems.

Dietary Recommendations: Minerals

Minerals in amounts equal to the RDAs should be taken in the diet each day.

While a dietary supplement of calcium is not recommended, it is especially important for women, adolescents, and anyone who restricts calorie intake to make careful food choices to assure adequate calcium in the diet.

Salt should be limited in the diet to no more than 4 grams per day, even less would be desirable (3 grams). Three grams equals one teaspoon of table salt.

Dietary Implementation: Minerals

A diet containing the food servings recommended for carbohydrates, proteins, and fats will more than meet the RDA standards.

Extra servings of green and yellow vegetables, citrus and other fruits, and other nonanimal source of foods high in fiber, vitamins, and minerals are recommended as a substitute for high-fat foods.

People who eat a sound diet as described in this chapter do not need a mineral supplement. Those who insist on taking a daily mineral supplement are advised not to take daily amounts larger than the RDA and only after following the guidelines for dietary supplements suggested later in this concept.

Water is a critical component in the healthy diet.

Though water is not on the list of the ten "key nutrients" because it contains no calories, provides no energy, and typically provides none of the ten key nutrients, it is very important to health and survival. Water is a major component of most of the foods you eat, and more than half of all body tissues are comprised of it. Regular water intake maintains water balance and is critical to many important bodily functions.

... andjoyohoxing