FROM NEW YORK comes the news that a vitamin company has failed to renew the contract of Billie Jean King in the wake of her admission that she once had a homosexual affair. King endorsed the vitamins on television, which suggested to the gullible that if they pop these particular pills they can rush the net the way she does. The question is whether the public will now think that by taking the vitamins they will become homosexual.

The question, of course, is ridiculous, but why then would the company not want to renew the contract? It would do so, presumably, because it thinks that King's value to them has been diminished ever since her affair became public knowledge. This is precisely what King must have feared, but it has become Billie Jean King's unenviable duty to have to reconcile fantasy with reality and in the process demolish some stereotypes about homosexuality.

No one could blame King for being hesitant to do what she has done. Homosexuals are hardly rewarded for announcing their sexual preference in this country -- maybe any country. There are some fields where it hardly matters, but it is no help to an actor, for instance, to be labeled a homosexual. Actors who have been have had a hard time sustaining their careers. The public does not want its fantasies messed with and it is hard to fantasize about some lover-boy movie star when the gossip columns are full of stuff about how the people he loves are of the same sex.

But Billie Jean King does not deal in fantasy. She deals totally in reality. She is, or was, one hell of a tennis player and it should matter not at all whether she rushed the net as a heterosexual, homosexual, bisexual or asexual. (I think that about covers it.) What matters is that she plays a swell game of tennis and is now one of the game's chief organizers. She has been instrumental in taking women's tennis to where it is today, which is more or less on a par with men's tennis. Billie Jean King's feminism is as sound as the dollar used to be.

Success, though, has come at a price. Like male athletes before them, women athletes have hitched their starts to commerce -- to endorsements and sponsors and big gates and television. They have allowed the sport, all sports, to become part of the entertainment busines. In this way, it has been disassociated from reality, from what the athletes really do, which is play a game.

It's unfair to blame this play-acting solely on the athletes themsleves. They do what they have to do to make a living -- sometimes a very good living. It's hard to imagine that any athlete who announced himself or herself as gay would not be punished economically for that sort of honesty, although it is a sure thing that some athletes, like some non-athletes, are homosexuals. And it is hard to fault the companies, aware as they are of strong feelings against homosexuals. What they want to do, after all, is sell products, not inform the public and lead some sort of crusade in favor of gay rights.

But together, all of them -- the athletes, the networks and the sponsors -- have concocted this fantasy land of athletics in which everyone is clean and heterosexual and a member of the Fellowship of Christian Athletes. They have taken our sexual prejudices and hung them around the neck or organized sports, insisting for the sake of the dollar that athletes adhere to a certain standard of behavior.

But now Billie Jean King's little secret -- lesbianism -- is a secret not more and that is a healty thing. It is as healthy as the revelations a while back that some male athletes are gay and the reason it is healthy is not just because it diminishes the pressures on the athletes themselves, but because it demolishes the stereotypes about hmosexuality -- that gay males are feminine, gay women victims of hormone disorders or that there is no place for them in sports. Nothing contradicts this more than the facts.

If the tragedy and pain of the Billie Jean King affiar does nothing more than put a human face on homosexuality, she will have accomplished quite a bit. If she does no more than shatter some stereotypes, she will have contributed mightily to at least a tolerance of homosexuals and homosexuality.

That would be quite a feat.