If you are a ZX81 owner, and would like to lose weight, The Computerised Diet might be of interest to you. It is a 'personalised' program, so after asking for your name, it goes on to ask your current weight and height, and your sex. Incidently, it was at this stage that I made my first mistake, of the classic 'not reading the instructions' variety, and entered my weight in stones rather than pounds. Consequently, when I proceeded to select my 'ideal' weight - 150 lbs. - I was told that I needed a weight change of 140 lbs. which would require a calorie intake of 2,100 calories! This program needs error-trapping!!

Upon entering my correct weight in pounds, I was told that I needed a weight change of 10 lbs., and a calorie intake of 2,100 calories daily. The next step is to record the information onto a table in the booklet that accompanies the cassette.

The second part of the PSA (Present Service Assessment), asks twelve questions about current eating habits i.e. "Do you eat quickly?", "Do you eat when bored?", etc. Your bad habits are then listed on the screen and you are asked to enter them in the booklet.

Prior to using the program, the user must have kept a record of all food consumed over three to seven days. This is entered to build up your DEP (Daily Eating Pattern). For each meal you enter the calories consumed, and your mood at the time: anxious, bored, depressed, etc. Tables in the booklet give calorie values of foods, etc. Your daily eating habit pattern is summarised to give your average daily calorie intake, the calorie change required to give your desired weight, and predominant mood at snacks. Again, the data should be entered into the booklet.

The first side of the cassette ends with printouts in graphic and tabular format of your present, and ideal, calorie intake for each meal of the day. You can save your eating pattern to enable your progress to be monitored - a blank cassette is provided for this purpose.

The reverse side of the cassette contains a menu building program. Briefly, the computer assists the user in developing the food groups (there are eight) and the servings of each group for each meal. This results in a balanced diet containing the requisite number of calories.

The two programs work quite well. Screen displays and data entry are generally clear and are well thought-out. The printouts are good and the booklet is helpful.

Doctors generally agree that dieting should be coupled with exercise if a lasting weight loss is to be achieved. Also that correct food balance is, if anything, more important than pure calorie-counting. Perhaps a development of this program to include all these factors would be a worthwhile aim. As it stands, I am sceptical that it would be of real benefit to the overweight.

Strangely, whilst the computer hobbyists spend many hours hunched over their machines and have pale complexions as a result, few in my experience, are overweight. Perhaps their preoccupation with computing leaves insufficient time for other indulgences.

Softchoice Ltd are at 52 Platts Lane, London NW3 7NT.