Q. Several years ago, I lost some weight using a combination of dieting and slimming pills.

To maintain my current weight, I continue to take about two pills a day. Will this produce any side-effects?

I follow a strict diet - soupy dishes, vegetables and fruits - every day with no carbohydrates. But for about two days every week, I allow myself to indulge in a lot more food which includes cakes, pastries and snacks. Will this erratic diet be harmful in the long term?

A. To lose weight, a person needs to take in fewer calories than he expends. Most slimming pills work by reducing energy intake - either by reducing appetite or blocking the absorption of dietary fat. Prolonged use of slimming pills is not recommended because, among other things, they may have an adverse effect on the heart.

Currently, most major professional bodies recommend a balanced nutrition diet in terms of calories consumed -

20 to 30 per cent from fat; 55 to 60 per cent from carbohydrates; and 15 to 20 per cent from protein.

Fruits are a good source of carbohydrates. Your diet for five days of the week looks good. The occasional indulgence is only human. Do try to keep the make-up of calories and the overall calories taken within the recommended range.

To maintain your weight, you should continue to monitor your food intake and embark on an exercise programme. Preventing weight gain after substantial weight loss probably requires about 60 to 90 minutes of moderate intensity physical activity per day. Adding resistance training to your exercise plan will help preserve muscle mass. Do consult your doctor before starting any exercise programme.

Dr Lee Chian Chau

This article was first published in Mind Your Body, The Straits Times on August 6, 2008.