The aim of this study is to investigate weather gradual weight loss achieved with healthy lifestyle changes influence hormonal factors affecting appetite and blood glucose control in obese people without presence of diabetes.

Obesity is becoming a growing and significant public health problem. Evidence from various national surveys over the last 25 years show that the prevalence of obesity and overweight in adults in England has increased threefold. There is still no clear evidence available to explain the epidemic levels of obesity. A number of neuro-endocrine factors have a role in the regulation of food intake and in the control of insulin secretion. We are particularly interested in measuring levels of a hormone called Glucagon-like peptide 1 (GLP-1) which is released from the intestine when food is absorbed. This hormone in turn has an influence on the production of insulin and another hormone, glucagons, both of which are involved in controlling blood glucose ('blood sugar') levels and appetite control.

There is some evidence, that obese people with normal blood sugar control show attenuated GLP-1 levels, however the evidence is contradictive and statistical significance is unclear. There is an ample of evidence that in established diabetes GLP-1 levels are attenuated, however it still remains uncertain whether the lower GLP-1 levels contribute to the pathogenesis of the condition or are a consequence of chronic hyperglycaemia or other hormonal and metabolic changes, though the observation that GLP-1 levels are lower in obese subjects suggests the possibility that the former may be the case.

Recently Bournemouth Diabetes and Emdocrine Centre (BDEC) conducted a research trial on effect of weight loss on GLP-1 levels in subjects with new onset type 2 diabetes. After 8 months intensive lifestyle programme average weight loss was 7.8 kg with significant and sustained improvements in clinical and metabolic parameters. Despite this, the GLP-1 levels remained unchanged.

None of the previous studies looked how gradual healthy lifestyle changes with sensible weight loss goals and increased activity levels effect GLP-1 levels in obese non-diabetic population.

Inclusion criteria:

1. BMI between 30-39.9kg/m2
2. Family history of diabetes (self reported)
3. Normal and impaired glucose tolerance
4. Obtain informed consent

Exclusion criteria:

1. BMI less than 30kg/m2 or more than 39.9kg/m2
2. Presence of diabetes or any other chronic disease or disability that might interfere with the study results
3. Anti-obesity or any other prescription medications that may interfere with the study results
4. Pregnancy
5. Unable to converse competently in English as special arrangements would need to be made for such people and this would be impractical in a group setting
6. Attending another weight management programme
7. Patients who would be unable to attend at least 75% of the programme sessions for medical or other reasons
8. Unable to provide informed consent.