Very low-calorie diets (VLCDs)
Very low-calorie diets, also known as VLCD, involve eating 1,000 calories a day or fewer for a limited time of up to 12 weeks.
Very low-calorie diets may be appropriate if other approaches to weight loss have not been effective.
Always seek medical advice before starting a very low calorie diet, as they are not suitable for some people, including those with eating disorders and epilepsy and women who are pregnant or breastfeeding.
VLCDs may be available through private weight loss organisations, including those offering special meal replacements.
Drawbacks of very low-calorie diets
To be healthy, we need a balance of foods from different food groups. It can be difficult to get good nutrition when calories are very restricted, or with diets where the same foods are eaten day after day.
Potential adverse effects of a very low calorie diet may include hair loss, fatigue and constipation, as well as some potentially more serious effects such as irregular heart rhythms and osteoporosis.
Also, once you go off the diet, you will be likely to put the weight back on unless you change your lifestyle and commit to healthy eating and regular physical activity.
By sticking to a long-term commitment, you can prevent your weight from drifting back up the scales.