人竟然有这么多的头发问题.docVIP

人竟然有这么多的头发问题！We tend to regard hair only as a reflection of our personal style, but as a living, growing part of our body, its also tied in to our physiology. Hair reflects internal changes -- things like sickness, nutrition and stress,?says dermatologist Paradi Mirmirani, M.D., a faculty member of the American Academy of Dermatology and staff dermatologist with Kaiser Permanente. There are three parts to your hair: the hair shaft (the fiber), the hair bulb (the root) and the hair cycle (the period of rest and regeneration). Most problems are related to one of these three things, says Mirmirani. Issue: Excessive hair shedding Each individual strand of hair has its own cycle, growing for six to eight years, resting for a few months, and then shedding. About 10 percent of your hair is shedding at any one given time,?Mirmirani says, pointing out that many things can interrupt the cycle and cause more hairs to shed earlier, including stress, fever, weight loss (even 10 pounds) or low iron levels. If youre noticing more shedding than usual, examine your lifestyle to see what might have changed or consult your dermatologist for tests. Issue: Hair that is dry and has lost its luster Oh, the things we do to our hair in the name of beauty, like daily blow-drying and using the flat iron. Hair becomes dry when the cuticle starts to break down and the inner fiber is exposed,?Dr. Mirmirani says. Excessive heat can cause this -- especially heat applied to wet hair. She recommends air-drying your hair partially before blow drying, only using the flat iron on dry hair, and using a daily conditioner. Remember that hair fiber with color is more prone to damage, so be extra cautious if you color-treat your hair. Issue: Brittle or easily breaking hair Some hairstyles can actually affect the health of your hairs bulb, Dr. Mirmirani says. She sees this a lot with hair extensions or ponytails pulled too tight, day after day. Think of it this way, if you keep pulling on the bulb of a plan