Some liver diseases are linked to obesity; 90% of morbidly obese individuals are thought to have fatty livers11. Obesity can also speed the damage associated with other conditions such as alcoholic liver disease12 and can decrease the effectiveness of treatments for hepatitis C 13,14.
It is important to maintain a healthy weight; to do this you need to balance the amount of food you eat with the energy you need. If you eat fewer calories than your body needs (especially if you are physically active) you will lose weight. If you eat more than you need, your weight will increase15.
Your BMI (body mass index) gives a guide as to whether you are a healthy weight for your height.
BMI = weight (kg) for example 95kg = 29.3
height (m) x height (m) 1.8m x 1.8m
Alternatively enter your details in the NHS Choices BMI calculator to get a BMI score:
- BMI below 18.5: under weight
- BMI 18.5-24.9: healthy weight
- BMI 25.0-29.9: overweight
- BMI above 30.0: obese.
People of South Asian origin may be at greater risk of ill-health at lower BMI ranges than those shown above, with a BMI of greater than 23 suggested as being overweight16.
The amount of energy we need differs according to our sex, age, weight and the amount of physical activity we take. For example, a small elderly woman will need less food than a young, active man5. As a basic rule of thumb, healthy adult men are advised to eat about 2,500kcal every day and women 2,000kcal a day. In general, patients with chronic liver disease need more energy and more protein than healthy people.
If you are trying to lose weight you should not ‘crash diet’. There is no quick and easy way to lose weight and ‘crash dieting’ may cause other health complications. Before attempting to lose weight you should consult your doctor so that they can advise you on the safest method of doing so. An increase in exercise and a decrease in calorie intake is usually the best route10.
If you have been diagnosed with advanced liver disease and are experiencing symptoms such as fluid retention in the abdomen, this will affect your weight and your BMI can be misleading. In this instance your diet will need to be managed very carefully by a dietitian, as it is possible to be overweight as a result of the fluid retention but to be malnourished17.
If you have been ill and have lost a lot of weight, you may not feel like eating, and keeping to a well-balanced diet may be difficult. Try to keep eating as much as you can, and ask your doctor or dietitian for advice on how to increase your calories and protein intake18.