Getting enough vitamin D appears to be especially important for older people, since many are low in the nutrient and research suggests that it may strengthen immunity against respiratory and skin-wound infections as well as bolster the bones.
Vitamin E might also help older people maintain an adequate arsenal of T cells, virus-fighting immune cells that typically decline with age. A recent study found that older people who consume relatively large amounts of vitamin E have improved immune-system response and a reduced risk of developing colds, perhaps by improving the function of those protective cells.
While taking a lot of vitamin and mineral pills might seem like the best solution, that's usually not the case.
Unlike foods, pills can deliver toxic doses of certain nutrients, resulting in side effects, drug interactions, and compromised immunity. Indeed, clinical trials have found either no benefit or increased risk in people who take certain nutrients in supplemental form.
"The key is to get the right amount—not too much and not too little," says Kevin High, M.D., an expert in immunology at Wake Forest University. For most people and most nutrients, that's doable if you eat a balanced diet, rich in fruits and vegetables, whole grains, low-fat dairy products, and modest amounts of fish, low-fat meat, nuts, and vegetable oils.
But even with that diet, some people—especially those over age 50 or so—may not get enough vitamin D.
They should consider a multivitamin. Other people who may also need one to plug nutritional gaps include:
- Dieters or picky eaters.
- Strict vegetarians.
- Women who are pregnant, likely to become pregnant, or breast-feeding.
- People who have a chronic gastrointestinal disorder, such as colitis or pancreatitis, that impairs absorption or digestion.
- People with chronic illnesses like diabetes and cancer, which can deplete nutrients.
