If dandruff is the only thing standing between you and a nice black shirt or sweater, you're not alone. At any one time, millions of people have this chronic scalp disorder, which is marked by itching and excessive flaking of the scalp -- and embarrassment.

The good news is that dandruff can usually be controlled. Mild cases may need nothing more than daily shampooing with a gentle cleanser. And stubborn flakes often respond to medicated shampoos. What's more, researchers have identified a yeast-like fungus that may cause or aggravate dandruff, a discovery that may lead to better treatments and even to a whole new wardrobe.

You can't prevent dandruff, but the Mayo Clinic says you can take steps to reduce your risk of getting this surprisingly persistent condition:

Learn to manage stress. Stress affects your overall health, making you susceptible to a number of conditions and diseases. It can even help trigger dandruff or exacerbate existing symptoms.

Shampoo often. If you tend to have an oily scalp, daily shampooing to remove the excess oil may help prevent dandruff.

Cut back on styling products. Hair sprays, styling gels, mousses and hair waxes can all build up on your hair and scalp, making them oilier. Some people may even develop allergies to various hair-care products.

Eat a healthy diet. For overall good health, include plenty of fresh fruits and vegetables, whole grains, and small amounts of lean protein in your diet. Get a little sun. Sunlight may be good for dandruff.

But because exposure to ultraviolet light damages your skin and increases your risk of skin cancer, don�t sunbathe. Instead, just spend a little time outdoors. But wear sunscreen on your face and body.