Q: I am 65 years old and, according to my doctor, in excellent physical condition. But I have a hard time controlling my weight. Besides being less active than when I was younger, is there any additional reason for the difficulty?

A: Yes. As we get older, body composition changes. The amount of adipose tissue, or fat, increases and the amount of lean tissue drops. This happens even in individuals who weigh not a pound more at 65 than they did 30 years earlier.

Adipose tissue is metabolically less active than lean tissue, and therefore burns fewer calories. This change in body composition can account for as much as a 15 percent decline in basal metabolic rate (the energy required to maintain normal body functions) over the four decades between 40 and 80 years of age. The rate of decline varies considerably from one individual to another. Some people in their 80s have BMRs as high as the typical 40-year-old.

Q: In a recent column you said there was no good evidence linking sugar and hyperactivity. But is there any support for the claim that a high sugar intake promotes criminal behavior?

A: No. Not only sugar, but white flour and several other foods have been libeled as causing criminal behavior. Even such basic foods as milk and oranges have been accused of triggering "brain allergies" that can lead to violent actions. While these and other equally bizarre claims and treatment proposals have been rejected by health professionals, they have been accepted as fact by some probation officers, social workers and criminologists, as well as a number of educators and legislators. Pressure has been put on some correctional institutions and even schools to limit the foods available.

At its annual meeting last fall, the House of Delegates of the American Dietetic Association voted to support the Position Paper on Diet and Criminal Behavior published six months earlier by the California Council Against Health Fraud, Inc. It called for an end to the use of unfounded, unscientific beliefs as a basis for dietary claims and procedures. Most appropriately, the first of seven direct statements in that paper asserts that nutritionally adequate and acceptable diets, determined on the basis of accepted dietary principles, must be available for all individuals in institutions.

Among other points, the paper stated there is no valid evidence showing that diet is an important factor in violence and criminal behavior, or that reactive hypoglycemia is a common cause of violent behavior. On the contrary, inappropriate dietary treatment, based on unsupported claims, can hinder efforts to identify, treat and prevent the true causes of aberrant behavior, and can lead to the dangerous belief that diets, not individuals, have control over and responsibility for behavior.

Q: I read that the FDA is developing an educational program on food safety for people involved in commercial food production. Can you tell me more?

A: The Food Protection Certification Program, scheduled to get under way this month, is designed to test and certify the thousands of people who supervise retail food operations.

The test includes 60 multiple-choice questions chosen from an original 1,200 and was developed by a 40-member committee composed of food industry experts, educators and government regulatory officials. A 17-member advisory and policy board, which will function as a permanent overseer of the program, then approved it.

The first objective was to design an examination for all candidates on what they should know about food management and protection. The test had to be acceptable to state and local regulatory agencies, and had to be geared to a level appropriate for people from many different backgrounds.

Those who pass will be listed in a national registry. Those who fail will be given a chance for additional study and training.

The testing will be conducted by the Center for Occupational and Professional Associations of the Educational Testing Service (ETS) in Princeton, N.J., at thousands of centers across the country. A $25 fee will go toward tuition when it is part of the training program. ETS will inform candidates who do not pass why they failed, and will be responsible for maintaining the registry.

The new testing program is voluntary. How much it will be used is unclear, but a survey conducted last year indicated that such a program would have widespread support. Its major impact is expected to be on food service and retail food stores, which account for about 750,000 establishments employing 10 million people.