A new simple test can help people work how much fat they are carrying - and all you need is a piece of string.
It takes just a few minutes to complete and it can be done pretty much anywhere.
Writing for the Mail on Sunday , Dr Michael Mosley explained that while BMI is often used as an indicator when working out how many people are overweight, the system has several flaws.
For example, as muscle is heavier than fat it can sometimes skew the results.
Instead he recommends the string test.
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All you need to do is get a ball of string and cut a piece which is as tall as you are.
Take the newly cut piece and fold it in half.
Wrap the folded string around your middle by your belly button and see if you can makes the ends meet.
Dr Mosley writes: "The build-up of visceral fat is normally the result of a number of different factors, which include eating too much sugary, starchy food, drinking too much alcohol (particularly beer), not doing enough exercise, feeling stressed and sleeping badly, and, of course, genetics.
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"Some people, when they put on weight, immediately put it on around the gut. I’m one of them. The good news is that studies show visceral fat responds well to weight-loss regimes and exercise.
"Any decent diet and exercise regime will help, but a rapid weight-loss regime that includes an element of intermittent fasting and fast exercise – high-intensity interval training, or HIIT – of the sort I recommend in my latest book, The Fast 800, seems to be particularly effective."
