Vitamins

Youngsters may be the ones urged to eat their vegetables and drink their milk, but experts say someone ought to be offering similar advice to adults. That’s because nutritional requirements change with age.

Older people may need more of vitamins such as B12 and folic acid, for example, because the ability to absorb these nutrients decreases over the years. And since aging reduces the skin’s capacity to synthesize vitamin D from sunlight, it’s essential that mature adults get enough.

It’s best to get all the necessary vitamins and minerals by eating well-balanced meals. But that can be difficult. If you’re unsure that you’re getting your share of nutrients, you may want to consider a daily multivitamin supplement, especially if your variety of foods is limited, you drink a lot of alcohol, or you have an impaired immune system. (Most experts hesitate to recommend individual vitamin supplements unless there’s a demonstrated need, because some vitamins are toxic in large doses.)

The chart on this page will tell you what the daily nutritional needs of mature adults are, and the role each nutrient plays.

Nutrient Needs
Vitamins		  RDA*
Vitamin A   	Women 800 IU 	Men 1,000 IU
Role: Aids new cell development; boosts the immune system; maintains bones, teeth, skin, eyes, mucous membranes. 
Selected sources: liver, carrots, sweet potatoes, fish, dairy products.

Thiamin (B1)	Women 1.1 mg  	Men 1.5 mg 
Role: Plays an important role in converting blood sugar into energy.
Selected sources: brewer's yeast, kidney beans, peas, lean meats.

Riboflavin (B2)	Women 1.3 mg 	Men 1.7 mg 
Role: Helps the body obtain energy from carbohydrates and proteins. Selected sources: milk, cheese, eggs, fish.

Niacin (B3)	Women 15 mg 	Men 19 mg
Role: Helps convert food into energy, synthesize DNA, and process fat. 
Selected sources: cottage cheese, lean meats.

Vitamin B6  	Women 1.6 mg	Men 2.0 mg
Role: Helps the body resist stress; may reduce symptoms of premenstrual syndrome. 
Selected sources: liver, whole-grain breads, potatoes.

Folic acid (B9) 	Women 180 mcg 	Men 200 mcg
(400 mcg for women of childbearing age) 
Role: Essential for production of red blood cells and proper nervous system development.
Selected sources: spinach, brewer's yeast, soybeans, orange juice.

Vitamin B12  	Women 2 mg	Men 2 mg
Role: Necessary for the nervous system to function; aids in red blood cell development.
Selected sources: fish, dairy foods, eggs.

Vitamin C 	Women 60 mg	Men 60 mg
Role: Maintains gums, teeth, bones, and connective tissue; helps the body absorb iron. 
Selected sources: orange juice, broccoli, green peppers, potatoes, strawberries.

Vitamin D  	Women 5 to10 mcg	Men 5 to10 mcg
Role: Maintains strong bones and teeth.
Selected sources: sunlight, fortified milk.

Vitamin E  	Women 8 mg	Men 10 mg
Role: Helps the body form red blood cells and use vitamin K; protects tissues from damage. 
Selected sources: vegetable oils, nuts, wheat germ. 

Vitamin K  	Women 65 mcg 	Men 65 to 80 mcg 
Role: Essential for blood clotting.
Selected sources: brussels sprouts, cabbage, liver. 

Major Minerals

Calcium 	Women  800 mg  	Men 800 to 1,200 mg 
Role: Essential for strong bones; enables muscles to relax and contract.
Selected sources: yogurt, cheese, tofu, broccoli.

Iodine:    	Women 150 mcg 	Men 120 to 150 mcg 
Role: Needed for proper thyroid function.
Selected sources: iodized salt, seafood, milk.

Iron   	Women 10 to 15 mg 	Men 10 to 12 mg 
Role: Delivers oxygen to cells via the blood. 
Selected sources: prune juice, chickpeas, spinach, cheddar cheese.

Magnesium  	Women 280 mg	Men 350 mg 
Role: Helps bones and teeth remain strong; keeps body's metabolism in balance.
Selected sources: soybeans, avocados.

Phosphorus  	Women 800 mg	Men 800 to 1,200 mg
Role: Participates in chemical reactions; aids growth, maintenance, and repair of tissues. 
Selected sources: red meat, fish, cheese, eggs.  

Zinc   	Women 12 mg  	Men 12 to 15 mg 
Role: Works with red blood cells to transport waste from tissues. 
Selected sources: meat, milk, wheat bran, yeast.

*RDA = recommended dietary allowance, which represents the daily amount the U.S. government believes is necessary to prevent deficiency. RDAs for pregnant and lactating women may be different.

Abbreviations: IU = international units; mcg = micrograms; mg = milligrams