''It was a real breakthrough'' he said. ''I also put myself on a strict diet, no fruit or juice and no carbohydrates, which were replaced by protein, which is converted to blood glucose much less rapidly. And after a year of following my own regimen, my diabetic complications, including night blindness, exhaustion and fatty tumors on the eyelids, started to reverse. At last I was feeling good.''

However, Dr. Bernstein related that when he tried to get doctors interested in his regimens, they were unimpressed. ''Only three doctors in 50 were willing to change the way they treated diabetics; no medical journals would publish my articles. I knew I was crying in the wilderness,'' he recalled.

''I remember trying to convince a drug company I knew to manufacture special tapes that you use for measuring blood sugar,'' he said. ''But their answer was that it was a useless market that had no volume. Today that 'useless market' generates over $600 million in annual sales of the tapes in the United States alone. And blood-sugar measuring machines have undergone a metamorphosis. They're now the size of ballpoint pens.''

Frustrated and unable to get doctors interested in his methods for controlling diabetes, Dr. Bernstein decided to leave the job he enjoyed and become a doctor. ''It was the only way to gain credibility,'' he said.

During his first year in medical school, he wrote a book explaining his method - entitled ''Diabetes: The Glucograph Method for Normalizing Blood Sugar.'' More than 25,000 copies have been sold.

Dr. Bernstein conceded, however, that he has detractors. ''There are doctors who think I have a messianic complex,'' he remarked. ''But the National Institutes of Health is testing my regimen at medical schools around the country. And when patients say they feel they have been reborn after they follow my regimen, I feel pretty good.''

Dr. Bernstein speaks at medical schools and on talk shows, and he publishes articles explaining his treatment. He said he literally trained his patents to become their own doctors and manage their own illnesses. For patients confused by the calculations required to find how much insulin to take and when to take it, Dr. Bernstein, the former industrial-management engineer, is working out a program that can be run on a pocket computer.