Obesity

Obesity is a long-term condition. If you have it, your body carries too much fat, and that can put your health at risk.

Obesity is a complex condition with more than one cause. Obesity and overweight happen when extra calories are stored in your body as fat.

Obesity is becoming more common. This is because the environment you live in makes it hard to make healthy food choices, and it makes physical activity difficult too. Some things that can contribute to obesity and overweight are:

• the cost of healthy food
• the cost of exercise
• time pressures
• where we live

Some underlying health conditions can also contribute to weight gain. These include:

• an underactive thyroid gland (hypothyroidism), where your thyroid gland doesn't produce enough hormones
• Cushing's syndrome, a rare condition that causes the body to produce too much steroid hormone

If conditions like these are diagnosed and treated, they won't be as much of a barrier to you losing weight.

Genetics can be a cause of obesity as well, because your genes can affect how your body stores and uses fat. Even so, there are still things you can do to try to maintain a healthy weight.

Doctors most often check your risk of obesity by working out your body mass index (BMI). Measuring your waist to height ratio can help as well.

BMI is a simple, widely used way to find out whether a person is a healthy weight for their height.

For most white adults, a BMI of 18.5 to 24.9 means your weight is in a healthy range. A BMI of 25 to 29.9 puts you in the overweight range. If your BMI is over 30, you are considered to have obesity.

For people from certain family backgrounds, health risks can begin at a BMI of 23, and the risk is higher from 27.5. These backgrounds are:

• Asian
• Chinese
• Middle Eastern
• Black African
• African-Caribbean

If your BMI is below 35, it can also help to measure your waist to height ratio. This shows if you're carrying too much weight around your tummy.

Ideally, your waist size should be less than half your height.

Diagnosing obesity in children and young people under 18 works a little differently. BMI measurements alone are not suitable, and they're difficult to measure at home too.

Your child's doctor may want to do other tests and check their overall health. If you're worried about your child's weight, speak to their doctor.

The most important ways of treating obesity are to:

• eat a healthy, reduced-calorie diet
• exercise regularly

To do this you can:

• eat a balanced, calorie-controlled diet, as your health professional recommends
• try to be more active (any increase in your current activity level will help you reach a healthy weight)

Your doctor may also recommend a weight management programme. These programmes help you move towards a healthy weight. They can also support you with weight-related health conditions like:

• type 2 diabetes
• cardiovascular disease (CVD)

More information on how to lose weight safely

You may also need medicines that can help with weight loss. There are a number of different types available:

• semaglutide
• liraglutide
• tirzepatide
• orlistat

Semaglutide, liraglutide and tirzepatide work in different ways to help you reach a healthy weight.

Orlistat works by reducing the amount of fat you absorb during digestion. Your doctor will know whether orlistat is right for you.

Doctors sometimes use weight loss surgery to treat people who are living with complex obesity. You may also hear it called metabolic and bariatric surgery.

If your child has obesity, treatment includes:

• making their diet healthier
• making sure they get more exercise

This can be hard to do, but there are things you can do to help.

The number of calories your child should eat each day depends on their age and height. Your doctor should be able to advise you on how many calories they should eat in a day.

Your child may be referred to a specialist in childhood obesity if:

• they develop an obesity-related complication
• there's an underlying condition which is causing their obesity

The specialist will recommend which treatment options would be right for them.

Several other conditions are linked with obesity and with extra weight around your belly. These include:

• type 2 diabetes
• cardiovascular disease
• fatty liver disease
• stroke
• obstructive sleep apnoea
• polycystic ovary syndrome (PCOS) and infertility
• some types of cancer, such as breast cancer and bowel cancer
• depression
• low self-esteem

People with obesity may also be more likely to have eating disorders like:

• binge eating disorder
• avoidant restrictive food intake disorder (ARFID)