Most diabetics can eat desserts and other sugary foods with their meals safely, according to a study that contradicts strict advice given diabetics for decades by doctors.

The main author of the striking new finding, Dr. John Bantle of the University of Minnesota, cautioned the nation's 10 million diabetics not to change their diets until his group's findings are confirmed by other researchers and not to overeat.

"During a meal, if the number of calories is kept constant, we don't think a pastry or dessert or candy is going to have any adverse effect on blood sugar levels," he said in an interview yesterday.

Bantle and five colleagues wrote, on the basis of test meals given 22 diabetics and the way they absorbed various sugars and starches:

"We see no reason for diabetics to be denied foods containing sucrose as long as weight reduction is not necessary and provided that sucrose is consumed in controlled amounts in nutritionally balanced meals that also contain protein and fat." Sucrose is ordinary table sugar.

The findings, being published in today's New England Journal of Medicine, are backed in an editorial in the journal praising the Minnesotans for helping to kill "old beliefs" about sugar and diabetes.

Ideas about shunning "simple sugars" such as sucrose "have been accepted so widely that few researchers have ever tested" them, according to the editorial by dietitian Phyllis Crapo and Dr. Jerrold Olefsky of the University of Colorado.

In recent years, they wrote, those ideas have begun to crumble. Now, they say, it is becoming clear that moderate amounts of sugar can be tolerated as part of a meal and that the belief that diabetics can tolerate only more complex carbohydrates, such as starches in rice, potatoes, peas and beans, is not necessarily accurate.

They said the effect of any sugars or starches on an individual are far from constant and may depend on the total diet or form of starch. For example, they reported that the wheat in pastas such as spaghetti and macaroni does not raise the blood sugar level as much as the wheat in bread.

Dr. Carl Sussmann, president-elect of the American Diabetes Association, said the group will review the findings.