The number of drug prescriptions to treat obesity has exceeded 1m in a year for the first time, government statistics showed today.

There has been an eightfold rise in the number of prescriptions in seven years, climbing to 1.06m in 2006, compared with 127,000 in 1999, according to the Health Survey for England 2006.

The two most commonly prescribed anti-obesity drugs were orlistat (marketed as Xenical), which prevents the absorption of some fat in the intestine, and sibutramine (Reductil), which affects the chemical messages that control how a person thinks about food.

One expert called the increasing use of such drugs "horrific", while opposition parties accused the government of resorting to short-term solutions to tackle obesity.

The report by the government's Information Centre for health and social care raised concern about obesity and heart disease.

Some 24% of adults were classified as obese in the health survey. Three times as many women as men were morbidly obese - 3% compared with 1%.

The study found more than one in 10 people aged 16 and over said they had been diagnosed with a cardiovascular disease, such as coronary heart disease or angina.

More than one-fifth of all men (21%) and nearly a quarter of all women (23%) were at very high risk of developing health problems such as heart disease.

The prevalence of diabetes, which is linked to obesity, was 5.6% among men and 4.2% among women.

The survey found poorer people were more likely to have cardiovascular disease, eat less fruit and vegetables and take less exercise. Men on high incomes were most likely to be overweight but not obese.

Increasing numbers of adults achieved the recommended levels of exercise in 2006. More than a quarter (28%) of women and two-fifths (40%) of men took part in at least 30 minutes of activity at least five days a week. This compared with 21% and 32% respectively in 1997.

The proportion of men eating five or more portions of fruit and vegetables a day rose from 23% to 28% between 2004 and 2006, and among women it rose from 27% to 32%.

In 2006, 19% of boys and 22% of girls aged five to 15 said they ate five or more portions of fruit and vegetables a day, compared with 13% and 12% in 2004.

Some 70% of boys and 59% of girls said they had taken part in 60 minutes or more of exercise on all seven days of the previous week, a similar level to 2002.

The report comes a week after the government launched a £372m strategy aimed at cutting levels of obesity in England. It includes £75m for a marketing campaign to promote healthy living to parents of young children.

Research is to be carried out into whether people should be given vouchers or other incentives to help them lose weight.

The shadow health secretary, Andrew Lansley, said: "The burden obesity is placing on our already overstretched NHS is becoming more and more unmanageable.

"Drug treatments are a short-term solution from a government that can't see beyond the short term. They've missed and scrapped obesity targets, slashed budgets for preventative measures and cut specialist staff. What we need to do is help people make healthy choices so they don't become obese in the first place."

The Liberal Democrat health spokesman, Norman Lamb, said: "This survey shows that our priorities in dealing with the spiraling obesity crisis are dangerously skewed. It should be easier for people to work exercise into their daily routines and it is vital that children know from an early age about the benefits of a healthy lifestyle."

Tam Fry, from the National Obesity Forum, said: "The percentage increase on the use of drugs is horrific. It shows the magnitude of the problem we have."

Denise Armstrong, a lifestyle manager at Heart Research UK, said: "Obesity is a complex condition that cannot always be reversed through diet and exercise alone. However, a healthy lifestyle programme including increased physical activity should go hand in hand with any drug therapy.

"It's important to remember that obesity patients may also benefit greatly from psychological support to help control appetite and address the root causes of weight gain."