Although virtually no two dieters may be alike either in energy expenditures or what it takes to get weight off, there are some general rules that can apply to anyone who wants to lose five pounds or 50 or more.

These are from Aaron Altschul, director of the Georgetown University Diet Management Clinic:

* Rule No. 1: The diet must be nutritionally balanced. Most people who are dieting get less than 2,000 or 1,500 calories a day. If you're very smart and work at it, you can get all your vitamins and minerals. If not, make sure you get them -- especially calcium -- from supplemental sources.

* Rule No. 2: People should rearrange their caloric density. This means reduce fat in the diet to less than 30 percent of total calories. In the normal American diet it is too high -- around 40 percent. Cut out pastry, butter, cheeses, nuts, sauces, mayonnaise, fatty meats and any but the most skimmed milk. Following this rule can reduce risks of cancer and cardiovascular disease even in people with no special weight problem.

* Rule No. 3: Alternate diet days or weeks. Very-low-calorie diets are dangerous when used day after day, without constant medical monitoring, but a fortified diet drink such as Sego Light (150 calories) may be used two or three days a week to give 600 calories a day. Or outline a week of 1,200 calories and alternate with a week of 2,000. A day or two a week of 600 calories is a good way to maintain an ideal weight in someone at risk of regaining.

* Rule No. 4: Examine your physical activity very critically and understand that if you are sedentary, you will find weight loss an almost hopeless endeavor.