Nutrient

Suggested Intake/Adults

Function

Description

Vitamin A
(preformed)

RDA: 1,000mcg or 5,000 IU

Used in the maintenance and growth of tissue, teeth and bones; vital for vision and mucous membranes.

Fat soluble. Women of childbearing age should not take more than 10,000 IU daily due to risk of birth defects, unless under the supervision of a physician.

Vitamin A
(beta-carotene)

No RDA set

Protects against cancer; important for eye health and immune function.

Fat soluble antioxidants. Main ones include beta-carotene, lutein and lycopene.

Vitamin D

DRI: 5 mcg (200 IU); 10 mcg (400 IU) for people over 50

Vital for healthy bones and proper utilization of calcium. Created by exposure to sunlight.

Fat soluble.

Vitamin E
(d-alpha tocopherol)

DRI: 22 IU natural vitamin E

Antioxidant that helps prevent heart disease, maintains cell membranes and protects lung, skin, liver and breast tissue.

Fat soluble. Natural vitamin E is absorbed and retained two times better than synthetic vitamin E.

Vitamin K
(phytonadione)

RDA: 65 mcg

Used in blood clotting and calcium binding.

Fat soluble. Gastrointestinal illness can impair absorption.

Vitamin C
(ascorbic acid)

DRI: 75 mg for women; 90 mg for men

Antioxidant used for blood vessel maintenance, wound healing, immune function and iron utilization.

Water soluble. Few toxicity concerns. People with kidney disease should consult with their medical practitioner.

Vitamin B1
(thiamine)

DRI: 1.1 mg
RDA: 1.1 mg

Used for muscles, nerve function, growth and utilization of carbohydrates.

Water soluble. Few toxicity concerns.

Vitamin B2
(riboflavin)

DRI: 1.1 mg
RDA: 1.3 mg

Necessary for the metabolism of amino acids and fatty acids and the formation of red blood cells and antibodies.

Water soluble. Few toxicity concerns.

Niacin

DRI: 14 mg
RDA: 15 mg

Maintains healthy cells, nervous system, skin and digestive function. Lowers cholesterol.

High doses of niacin can cause flushing and itching skin; the form niacinamide does not cause this reaction but has no effect on cholesterol.

Vitamin B6
(pyrodoxine)

DRI: 14 mg
RDA: 15 mg

Used to metabolize protein and to form antibodies, neurotransmitters and hormones.

Toxicity is relatively rare, but an excess of 500 mg daily can damage the nervous system.

Biotin

DRI: 30 mcg

Used in metabolism of fats, carbohydrates and proteins.

No toxicity concerns, as excess is easily eliminated through urine.

Pantothenic Acid

DRI: 5 mg

Used in synthesis of fatty acids and cholesterol, including byproducts such as bile, vitamin D and hormones.

No toxicity concerns. Pregnancy, lactation and stress may increase concerns.

Folic Acid

DRI: 400 mcg
RDA: 18 mcg

Necessary for red blood cell formation and cell division. Reduces homocysteine, a risk factor for heart disease.

Folic acid deficiency is widespread in women of childbearing age and can cause birth defects in infants.

Vitamin B12

DRI: 2.4 mcg
RDA: 2 mcg

Necessary in protein, fat and carbohydrate metabolism; blood cell formation; and maintenance of nervous system.

Many adults over 50 lose their ability to absorb B12 from food and require supplementation.

Choline

DRI: 10-100 mg

A building block of neurotransmitters necessary for brain function.

Important in the prevention of brain disorders, including Alzheimer's disease.

RDA: Recommended dietary allowance. A set of nutrient standards established by the United States Department of Agriculture (USDA).

DRI: Dietary reference intake. Currently being established by the National Academy of Sciences. DRIs provide an updated set of nutrient standards. In some cases, a tolerable upper intake level (TUIL) is listed. These upper levels are not intended as a recommended level of intake. Levels of nutrients for the suggested intake column are based on adult females, ages 19-50. This information is not intended as medical advice.