Belly fat could be a sign that your health is at risk, with Type-2 diabetes and heart disease among the associated dangers.  We found that diet, rather than exercise, is the best way to rein in the belly.

Using our calculator below, you can work out how many calories you can consume to try to lose an inch in four weeks. It tells you how many calories you need each day to maintain your weight, and you should reduce that figure by 500 calories to start reducing your weight and belly fat quite quickly

 The volunteers reduced their waist sizes by an average of 1 inch for every 4lb (1.81kg) they lost.

 So if you lose 1lb (0.45kg) a week you could hope to reduce your waistline by an inch after four weeks.

Dieticians advise that if you eat 500 calories less than your daily requirement you will lose about 1lb every seven days (expect some variation from person to person).

 This chart shows you how many pounds you can hope to lose per week based on how many calories you cut out of your daily diet.

What can you eat?

Each volunteer was encouraged to measure portions based on the size of their hands.

Aim for a daily intake of:

 Three fist-sized servings of carbs   

 Two palm-sized servings of lean protein

 Two cupped handfuls of vegetables or salad

 Two fist-sized servings of fruit

 Two servings of fat or oil covering the tip of your thumb.

Generally, you can eat your usual foods, so long as you reduce the portion size. Avoid or limit sugary and high-fat foods, such as fast foods.

The speed of waist reduction varies from person to person, so even if you reduce your calorie intake by the suggested amount, your results may differ.

As time passes you will lose weight and you'll need to recalculate your calorie requirement. At your new weight you'll find your daily requirement has dropped. So you need to drop again to keep 500 calories below your daily requirement. By recalculating you will keep losing 1lb (0.45kg) a week.