Two thirds of adults say they have improved their diet or exercise over the past year in a sign that the Government may be starting to win the war on obesity.

A poll of 2,000 adults for the National Consumer Council found that 63 per cent had changed their behaviour in the past 12 months with the deliberate intention of becoming healthier.

In an indication that the healthy eating message is finally getting through, the respondents were eating more fruit and vegetables, shunning salty food and cutting down on convenience meals.

If applied to the population of the UK, the findings suggest that about 30 million adults have tried to become healthier.

However, some groups of society - the poor, the old and people living on their own - do not yet seem to be changing their diets.

The survey found that more women (66 per cent) than men (61 per cent) were likely to have changed.

Women under 34 were more likely to have sought out healthier ways while men over 55 were least likely to have made changes.

Almost half (45 per cent) of the people on lower income groups D and E had not changed their lifestyles.