The bigger the star, the shorter the lifespan, that's what astronomers say. It's a phenomenon that likewise applies to movie luminaries, as the painful self-sabotage of Lindsay Lohan and Mel Gibson testify. Lohan, 24, and Gibson, 54, at their best charismatic and personable actors, are at their worst in this week's sequels to past bad behavior. Are both deliberately committing staricide, trying to end their careers?

Gibson's a big boy (although acting like a little one), and has been a star for almost 30 years. That's a century in Hollywood years. If he can't rebound, he'll be missed on screen, but he's had a good ride.

Lohan, however, is a symptom of a much more troubling syndrome: Teen-Star Disorder (TSD) -- the challenge of transitioning into adult life and adult roles.TSD effectively killed the careers of Shirley Temple and Mickey Rooney and Macaulay Culkin. It may have been a precipitating factor in the deaths of River Phoenix and Corey Haim. Somehow, Elizabeth Taylor, Natalie Wood, Jodie Foster and Leonardo DiCaprio passed through the awkward age and emerged relatively intact. Foster had the good sense (and grades) to go to college, taking herself off the Hollywood meat market until she had matured. (Natalie Portman and Claire Danes followed her excellent example).

Handled by handlers and also by parents for whom they are meal tickets, teen stars are rebels with a cause, rebels who often dump their guides at the time when they most need guidance.Should Hollywood be like the NBA and not draft teen stars straight out of high school, insisting that they take a gap year to mature?

Many teen stars hoping to graduate their adolescent fanbase and attract an adult  following do so by leaving PG behind for R-rated material, engaging in a kind of self-exploitation. Female teen stars court sex (as Dakota Fanning in Hounddog and The Runaways, and Lohan in Georgia Rule) and male teen stars court violence (as Leonardo DiCaprio did with The Basketball Diaries and Daniel Radcliffe did with the stage version of Equus). But what's rated R -- sex, violence, profanity and drugs -- although limited for adult consumption, is not necessarily adult.

From Annette Funicello to Lindsay Lohan to Miley Cyrus the company best known for manufacturing  and junking  teen stars is Disney. While I'm not willing to go quite as far as Danger Guerrero in this Disney-bashing piece where he accuses the corporation of creating "a perpetual whoredom machine," manufacturing jailbait cuties who appeal to males of all ages, I have to admit that he has a point.

Is there a cure for Teen-Star Disorder? Should Disney and Nickelodeon be obligated to send their teen stars to finishing school and prepare them for real adult life? Your thoughts?