The next time your teenager asks for a pair of Air Nikes or Guess jeans, consider this before you cringe at the cost: In a real sense, teenagers are what they wear.

Clothing plays a significant role in an adolescent's social acceptance, participation in school activities, leadership potential and positive self-esteem, say researchers who have studied adolescents and clothing."The teenage years tend to be years of uncertainty and, to a degree, lack of self-confidence," said Charlene Lind, an associate professor of clothing and textiles at Brigham Young University. "Clothing is used as a social support system. It makes a difference in the way (teenagers) judge each other and the way they judge themselves."

Lind cites research that found teenagers, particularly between the ages of 13 to 15, based their own self-esteem on how much they dressed like their friends. Some teenagers told researchers they would participate in more types of activities if they had the right type of clothes.

Others admitted they sometimes refused to go places because they were embarrassed because of their clothing.

In another study, researchers found girls new to a high school wore the same clothes popular girls were wearing as a means of winning acceptance.

But not all teens consider clothing important or even want to dress like their peers, Lind said. In fact, research has shown that while clothing plays an important part in teenage boys' achieving leadership positions, it is of little importance once they've reached them.

"This is why parents need to look at each child's situation differently," Lind said. "One child may have a strong social support network and not place much emphasis on clothing. But another child may feel quite insecure and need that extra reinforcement."

Lind is not advocating that parents mortgage their homes to fill their teenagers' closets. But she does say parents need to allow their children some choice in what they wear - even if it means purchasing one piece of clothing instead of several.

"No child should be allowed to spend an inordinate amount on his or her appearance," Lind said. "But parents need to realize just how important having the right clothes is to teenagers."

There are bound to be conflicts over teenagers' clothing choices. Lind suggests parents remember their own teenage years and maintain a sense of humor.

"Adults sometimes get very uptight about what the neighbors will think," Lind said. "I think the probability is the neighbors are going through the very same thing."

While some adolescent clothing choices can bear real consequences - dressing in gang colors, for instance - parents need to realize teens don't attach the same meanings to clothing that they often do, Lind said.

And meanings associated with clothing changes. Beards and denim jeans were once a symbol of protest; dressing in black and having pierced ears no longer carry the negative connotations they once did.

Teenagers, Lind said, have been challenging dress standards for generations. When the hobble skirt of 1908 and the flapper styles of the 1920s came out, parents were aghast and even sought to control these fads through dress codes and legislation.

"Even then, experts on adolescence saw such rebellious behavior more as a reaction to the pressures of impending adulthood and counseled tolerance for a behavior that might be annoying but not dangerous," Lind said.

It helps to keep in mind: teenage years are temporary and so are clothing fads.