Slim body may still have dangerously high levels of fat, according to the British Medical Research Council. Even super-slim people could have high levels of internal fat collected around their vital organs like heart, liver, kidneys and pancreas, doctors demonstrated by using MRI body scanners

    "The fat we can see on overweight people is subcutaneous fat," The Daily Telegraph quoted Dr Ron McCoy, Melbourne-based spokesperson for the Royal College of Australian GPs, as saying. However, what could be more dangerous is visceral fat or the fat we can't see but which surrounds vital organs.

    Dr McCoy said: "Visceral fat is metabolised by the liver, which transforms it into cholesterol. Cholesterol circulates in the blood and can collect in your arteries, creating heart disease and high blood pressure."

    Visceral fat is also believed to produce harmful hormones and proteins than subcutaneous fat, affecting glucose levels and leading to the onset of type 2 diabetes and other health problems.

    A sedentary life style and fat diet are the main culprits in fat accumulation inside the body.