Obesity and Overweight - A Summary

Are you obese or overweight?

Body mass index (BMI) is a measure of how much of your body is made up of fat. It relates your weight to your height. Your practive nurse can weigh and measure you and tell you your BMI. If your BMI is over 25, but below 30, you are 'overweight'. If it is 30 or above, you are 'obese'.

Waist size is another measure. Your increased health risk is greater when the extra fat is mainly around your waist ('apple shaped'), rather than mainly on your hips and thighs ('pear shaped'). As a rule, a waist measurement of 102 cm or above for men (92 cm for Asian men) and 88 cm or above for women (78 cm for Asian women) is a significant health risk.

What causes obesity and overweight, and who does it affect?

About 2 in 5 adults in the UK are overweight and a further 1 in 5 are obese. The main causes of obesity are: overeating and/or eating the wrong kinds of food; little physical activity; some people inherit a tendency to be obese; a combination of these reasons.

What are the benefits of losing weight?

Many diseases are more common in obese and overweight people, and you are less likely to develop them if you lose some weight. They include: diabetes, high blood pressure, stroke, heart problems, some types of cancer, arthritis of the back and legs, gallstones, menstrual problems, incontinence of urine, breathing problems, some complications of pregnancy, and depression.

What is more, in most cases, much of the health benefits come with losing the first 5-10% of your weight. This is often about 5-10 kg. (10 kg is about one and a half stone.) If you are obese, on average, if you reduce your weight by 10%:

• You are much less likely to develop the conditions listed above, such as diabetes.
• If you have high blood pressure, osteoarthritis, or diabetes, these conditions are likely to improve. If you are taking medication for these problems, you may need a reduced dose.
• Your chance of dying at any given age is reduced by about 20%. This is mainly because you are less likely to die from heart disease, stroke, diabetes, or obesity related cancers.

Also, it is difficult to measure how much 'quality of life' is improved if you lose some weight. Many people feel better in themselves, and have more energy.

How can I lose weight?

The best chance of losing weight, and keeping the weight off, is to be committed to a change in lifestyle. This includes eating a healthy diet and doing some regular physical activity. Another leaflet in this series called 'Weight Reduction - How to Lose Weight' gives more detail. Medicines to help with weight loss are an option in some cases. But, they are not 'wonder-drugs', and you still need to eat less. Doctors are given guidelines on when to prescribe these medicines.

© EMIS and PIP 2006   Updated: June 2006   PRODIGY Validated