BEHIND THE BESTSELLERS : Write Book, Become Famous

That’s how it used to work. No more. Nowadays, you become famous first. You land a radio or television show or play a juicy role in a headline-grabbing scandal and then, and only then, do publishers come calling. Just check out the current Non-fiction Bestsellers list: Howard Stern, Jerry Seinfeld, Rush Limbaugh and Kathie Lee Gifford.

The latest author to join this self-promoting crew is Susan Powter, infomercial diva and fitness queen, with her book, “Stop the Insanity!” (Simon & Schuster: $22.). You know Powter. She’s that incredibly svelte, crew-cut blond--the first time you see her you think, hey, when did Annie Lennox start doing info-mercials?

Once a depressed, divorced, 260 pound fatty who couldn’t walk to the end of the block without stopping to catch her breath, Powter’s now a perfectly toned size 4. She lost the weight and she wants you to, too. How? It’s what you eat that counts, Powter contends, not how much. Scrutinize labels and multiply the number of fat grams per serving by 9 (there are nine calories in every gram of fat). Then divide that number by the calories per serving. If the answer is more than 30, that means the fat content exceeds 30 percent of the total calories and Powter advises passing the stuff up. Chow down instead, she says, on “high-volume, high quality (unprocessed), low-fat” foods, especially whole grains (brown rice, bulgar, kasha, etc.), legumes (beans, peas1, lentils, etc.) and vegetables. And exercise regularly. All this makes good sense. The haircut, though, is extreme.