Q: My mother is a diabetic and regularly uses sugar free tablets containing aspartame. Are they healthy and safe for her? What care should she take to keep her sugar level in control?

A:Scientists have found that aspartame is generally safe for most people to consume. In the United States, the FDA recommends no more than 50 milligrams of aspartame per 1 kg of body weight per day for adults but the average person consumes less than 2% of this amount each day. Certain people with the genetic disease phenylketonuria (PKU) have a problem with aspartame because they do not effectively metabolise the amino acid phenylalanine, one of aspartames components. High levels of this amino acid in body fluids can cause brain damage. Aspartame is safe for diabetics because it sweetens without the calories or rise in blood sugar levels.