Blondes may have more fun, but they also have more oily hair. And those with silky, baby-fine hair tend to have the worst problems with oiliness.
The reason is that those with finer hair have more hair per square inch of scalp. At the base of each hair shaft are sebaceous glands, which produce sebum, the fatty "oil" in oily hair. The more hair, the more oil glands. And the more oil glands, the more oil.
Blondes with fine hair have as many as 140,000 oil glands on their scalps, according to hair-care specialist Philip Kingsley. Compare that with redheads, who average 80,000 to 90,000 hairs per head. They rarely have oily hair, he says. Brunettes typically fall somewhere in the middle.
The texture of your hair also makes a difference, says Thomas Goodman Jr., M.D. Oil wicks onto fine, straight hair very easily. Wiry hair doesn't seem to get as oily.
Intense heat and humidity can also accelerate oil production. So can hormonal changes. For instance, androgen, a male hormone, can activate the sebaceous glands. Stress boosts bloodstream levels of androgen in women as well as in men.
Because they have more androgen than women, men tend to have oilier hair. Another reason is that men tend to have finer hair than women, says Kingsley. Men average 311 hairs per square centimeter of scalp, compared with 278 for the average woman. "That's a significant 10 to 15 percent difference," he says.
Since you're stuck with the type of hair Mother Nature gave you (if not the color), here's how to combat oily hair.
Lowell Goldsmith, M.D., is a professor of dermatology and chairman of the department of dermatology at the University of Rochester School of Medicine and Dentistry in New York. He specializes in hair disorders.
Thomas Goodman Jr., M.D., was formerly an assistant professor of dermatology at the University of Tennessee Health Science Center in Memphis. He is the author of Smart Face.
Philip Kingsley is the author of Hair: An Owner's Handbook.
This should be done right before the shampoo, never between shampoos, says Kingsley. That little bit of extra oil expressed during a scalp massage would make your hair feel even more oily.
Left on its own, oily hair tends to be limp and lank. To coax more fullness into it, be creative with your blow-drying technique, says Kingsley.
Squeeze the juice of two lemons into a quart of the best water you can find, says hairstylist David Daines. Distilled water is a great choice.