If you are obese, you weigh much more than is healthy for you. This is because your diet contains more calories than your body uses up. The extra calories are stored as fat.

To lose weight you need to take in fewer calories each day than you use. You can do this by following a weight loss programme that includes a diet and exercise. You may also have behaviour therapy to help you change the way you eat and exercise. Your weight loss programme may also include drugs.

Original Text: guardian.co.uk 09/02/2010

BMJ Group, Tuesday 9 February 2010 00.00 GMT

Your weight has probably crept up over many years. It's best to lose weight the same way you gained it: slowly and steadily. You should aim to lose 0.5 kilograms to 1 kilogram (1 to 2 pounds) each week. Work with your GP or practice nurse to set yourself short-term goals that you know you can achieve.

Key points about treating obesity

• You have the best chance of losing weight if you combine diet and exercise with behaviour therapy to help change the way you eat and exercise.
• A low-calorie diet and regular exercise can help you lose 5 percent to 10 percent of your weight in about six months. If you weigh 100 kilograms (220 pounds) this means you may lose 5 to 10 kilograms (11 to 22 pounds).
• Losing 5 percent to 10 percent of your weight (and keeping it off) may not sound like a lot but it lowers your risk of health problems and will help you feel better.
• Diet pills such as orlistat (brand names Xenical and Alli) and sibutramine (Reductil) may help you lose weight. But they have side effects. And you will still need to stay on a diet and exercise.
• Once you've lost weight it can be difficult to keep it off. You still need to be in a weight loss programme, with regular support from a health professional.
• If you're very overweight or your weight is an immediate threat to your health, you may need weight loss surgery to help you lose weight quickly. This type of surgery is called bariatric surgery. There are several different operations.
• People who have surgery usually lose about 27 kilograms (about 60 pounds) in the two years after their operation. And most people keep their weight off. But there are serious risks with surgery. There are several different types of operation.

The National Institute for Health and Clinical Excellence (NICE), the body that decides which treatments should be available on the NHS, has published guidance for doctors and the general public on the diagnosis, care and treatment of people with obesity.[1] This includes information about people who may need weight loss surgery. To find out more, read Who has weight loss surgery for obesity?

To find out more about helping children keep to a healthy weight, see Weight problems in children.

Treatments for obesity

Which treatments work best? We've carefully weighed up the research and divided the treatments into categories.

You can find out more about each treatment by clicking on the links below.

For help in deciding which treatment is best for you, see .

Treatments that work

• Diet, exercise and behaviour therapy: If you follow a diet, get more exercise and take advice from a health professional, you'll lose weight. More...

Treatments that are likely to work

• Gastric bypass: This operation is a type of bariatric surgery. The surgeon uses staples to make a small pouch in your stomach. More...
• Gastroplasty: This operation is similar to a gastric bypass. More...
• Gastric banding: This operation is another type of bariatric surgery, but it's reversible. An adjustable band makes a small pouch in the top part of your stomach. More...
• Biliopancreatic diversion: This operation is another type of bariatric surgery. The bottom part of your stomach is removed. More...

Treatments that work, but whose harms may outweigh benefits

• Orlistat: This drug reduces the amount of fat you absorb from food. Its brand name is Xenical. There's also an over-the-counter version that contains a lower dose, called Alli.More...
• Rimonabant: This drug is not available anymore because of safety concerns. More...
• Sibutramine: This is a type of drug called an appetite suppressant. Its brand name is Reductil. More...

Treatments that need further study

• Sleeve gastrectomy: This operation closes off three-quarters of the stomach, leaving a narrow tube. More...

Other treatments

• Other diet pills: These pills are either not available in the UK or are not recommended for use. But we have included them in case you have some questions about them. They include fenfluramine, phenylpropanolamine and phentermine. More...

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