For years the government and health experts have suggested that exercise and a calorie controlled diet is the single best way to lose weight and manage your weight.

This advice hasn't fallen on deaf ears. Between 1974 and 2004 the average calorie intake of people in the UK decreased by 20 percent and the amount of fruit eaten has increased by 20 percent. The UK population is also doing 27 percent more exercise than 1997. But the obesity levels and the number of people contracting Type 2 diabetes is still increasing.

So, if we are eating less and exercising more, how is this possible?

Well, there are a number of issues. Firstly, the government and health expert advice suggests a low fat diet which replaces fat with complex carbohydrates. Why? Dietary fat contains twice as many calories as complex carbs BUT crucially eating fats within your diet tricks the mind and body into feeling fulfilled rather than craving more calories, something that carbs tend to do.

Not all fats are bad fats. Many fats food in nuts, seeds and fruit actually help reduce the threat of heart disease and can help with weight management. However, the government still suggest that because fats contain twice as many calories as carbohydrates, eating more fat will lead to weight gain and an increased risk of contracting coronary heart disease (CHD).

Secondly, eating carbohydrates increases the level of insulin within the body, driving the energy from carbs (which are converted in sugar) quickly into the blood stream, which if it isn't used, is then converted rapidly into stored energy, i.e. body fat.

Of course with more and more people leading sedentary lifestyles it is likely that this rapid rises in insulin will lead to weight gain.

Finally, there is no solid scientific evidence to suggest that exercise makes us slimmer. In fact studies show that gym sessions etc can trick the exerciser into thinking that they can eat more calories to compensate for the energy used within their exercise sessions. Usually this calorie compensation either means the dieter eats the same number of calories burnt during exercise - meaning there is no calorie deficit, hence no weight loss, or the dieter actually over-compensates and actually eats more calories - meaning weight gain will actually occur.

The feeling is that UK government are basing their weight loss and dietary information on out of date studies and out of date dietary ideas.