Micronutrients in the Diet

No one food can provide all of the micronutrients, so you are encouraged to eat a variety of foods. Also, food preparation can affect the amount of nutrients that remain in the food, especially when cooking vegetables. To

 

increase the retention of vitamins while preparing a meal:

♦ Cook food in just enough water to prevent
burning, do not soak.

♦ Cook vegetables only until they are crisp and
tender.

♦ Steam or stir-fry foods to retain the most
vitamins.

♦ Use leftover cooking water for preparing

soups and sauces to use the water soluble vitamins that were leached out.

♦ Cut and cook vegetables shortly before serving or store them in
an airtight container.

The amount of minerals that will be absorbed from foods depends upon a number of factors, such as:

♦ The presence of other dietary constituents, such as dietary fiber
and other minerals.

♦ Medications.

♦ The body's need for the mineral and the mineral's chemical form.

♦ The integrity of the intestinal tract.

Many things can affect your body's ability to properly absorb vitamins and minerals. These include caffeine, tobacco, antibiotics, aspirin, alcohol and stress. For example, drinking coffee or tea with meals can decrease iron absorption and taking antibiotics can increase your Vitamin B needs.

Table 2-2. Requirements and Functions of Vitamins

Fat Soluble Vitamins	Some Important Functions	Food Sources
Vitamin A: Retinol, Retinoids, Carotene 800-1,000 µg. RE or 5,000 International Units (IU).	Growth and repair of body tissues, immune function, night vision. Carotene is the water soluble form with antioxidant properties.	Oatmeal, green and yellow fruits and vegetables, liver, milk.
Vitamin D: 5-10µg. or 200-400 IU.	Regulates calcium metabolism and bone mineralization.	Fortified milk, egg yolk, salmon, sunlight.
Vitamin E: alpha-Tocopherol, 8-10 mg.	Antioxidant, protects cell membranes, and enhances immune function.	Fortified cereals, nuts, wheat germ, shrimp, green vegetables.
Vitamin K: 60 - 80 µg.	Assists in blood clotting and calcium metabolism.	Green and leafy vegetables.
Water Soluble Vitamins	Some Important Functions	Food Sources
Vitamin B1: Thiamin, 1.0-1.5 mg.	Needed in energy production, CHO metabolism, and growth. Supports muscle, nerve, and cardiovascular function.	Fortified cereals, legumes, pork, nuts, organ meats, molasses, yeast.
Vitamin B2: Riboflavin, 1.2 -1.7 mg.	Essential for energy metabolism; growth and tissue repair.	Cereals, liver, milk, yogurt, green leafy vegetables, nuts, whole grain.
Vitamin B3: Niacin, Niacinamide, Nicotinic acid 13-19mg.	Essential for energy metabolism, blood circulation, nerve function, and appetite.	Lean meat, seafood, milk, yeast, fortified cereals, whole grain.
Vitamin B5: Pantothenic acid, 4 - 7 mg.	Essential for energy metabolism and nerve function.	Legumes, meat, fish, poultry, wheat germ, whole grain.
Vitamin B6: Pyridoxine HCl, 2 mg.	Essential for CHO and protein metabolism, immune function, red blood cell production, nerve function.	Oatmeal and cereals, banana, plantain, poultry, liver.
Folate: Folic acid, Folacin, 400 µg.	Vital for red blood cell synthesis. Essential for the proper division of cells. Maternal folate deficiency may result in an infant with birth defects.	Fortified cereals, green leafy vegetables, liver, lentils, black-eyed peas, orange juice.
Vitamin B12: Cobalamin, 2 µg.	Required for red blood cell production, energy metabolism, and nerve function.	Ground beef, liver, seafood, milk, cheese.
Biotin: 30- 100µg.	Participates in energy metabolism, fatty acid formation, and utilization of the B vitamins.	Legumes, whole grain, eggs, organ meats.
Vitamin C: Ascorbic acid, Ascorbate 60 mg.	Antioxidant, role in growth and repair of tissues, increases resistance to infection, and supports optimal immune function.	Cantaloupe, citrus fruit, strawberries, asparagus, cabbage, tomatoes, broccoli.
From the 1989 RDA and 1998 DRIs for healthy adults 19 to 50 years. CHO = carbohydrates. mg= milligrams, µg= micrograms.

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Table 2-3. Requirements and Functions of Minerals

Mineral	Some Important Functions	Food Sources
Boron Unknown	Important in bone retention.	Fruits, leafy vegetables, nuts, legumes, beans.
Calcium 1,000-1,300 mg.	Essential for growth and structural integrity of bones and teeth; nerve conduction; muscle contraction and relaxation.	Yogurt, milk, cheese, tofu, fortified juices, green leafy vegetables.
Chromium1 50 - 200 µg.	Participates in CHO and fat metabolism; muscle function; increases effectiveness of insulin.	Whole grains, cheese, yeast.
Copper1 1.5-3mg.	Essential for red blood cell production, pigmentation, and bone health.	Nuts, liver, lobster, cereals, legumes, dried fruit.
Iron2 10-15mg.	Essential for the production of hemoglobin in red blood cells and myoglobin in skeletal muscle, and enzymes that participate in metabolism.	Liver, clams, oatmeal, farina, fortified cereals, soybeans, apricot, green leafy vegetables.
Magnesium 280 - 350 mg.	Essential for nerve impulse conduction; muscle contraction and relaxation; enzyme activation.	Whole grains, artichoke, beans, green leafy vegetables, fish, nuts, fruit.
Manganese1 2 - 5 mg.	Essential for formation and integrity of connective tissue and bone, sex hormone production, and cell function.	Nuts, legumes, whole grains.
Phosphorous 800-1,200 mg.	Essential for metabolism and bone development. Involved in most biochemical reactions in the body.	Fish, milk, meats, poultry, legumes, nuts.
Potassium3 2,000 mg.	Essential for nerve impulse conduction, fluid balance, and for normal heart function.	Squash, potatoes, beans, fresh fruits (bananas, oranges) and vegetables (tomatoes).
Selenium 55 - 70 µg.	Antioxidant, works with vitamin E to reduce oxidation damage to tissues.	Meats, seafood, cereals.
Sodium4 500 - 2,400 mg.	Essential for nerve impulse conduction, muscle contraction, fluid balance, and acid-base balance.	Table salt, canned and processed foods.
Zinc 12-15mg.	Involved in metabolism, immune function, wound healing, and taste and smell sensitivity.	Seafood, beef, lamb, liver, eggs, whole grains, legumes, peanuts.

From the 1989 RDA and 1998 DRIs for healthy adults 19 to 50 years. CHO = carbohydrates. Estimated safe and adequate daily intake range - meets requirements of individuals and avoids the danger of toxicity (Food and Nutrition Board, 1989). ²Men should consult a physician before taking iron supplements. 3The minimum daily requirement for potassium is 2,000 mg. 4The minimum daily requirement for sodium is 500 mg. or 1,250 mg. of salt. Salt is 40% sodium and 60% chloride. One teaspoon of salt (5g sodium chloride) has 2g (2,000 mg) of sodium. mg= milligrams, µg= micrograms.