Primary Outcomes:

1. To study cross-sectional associations between diet, physical activity, T2DM and weight in subjects 2 yrs after surgery.

2. To study if subjects receiving extra guidance in diet and physical activity experience less weight gain compared to a control group.

   Secondary Outcomes:

3. To study the association between vit.D levels and T2DM.

4. To study the association between weight change and QOL.

5. To validate the new guidance strategy by recording food intake, energy expenditure and physical activity level.

6. To study if subjects receiving extra guidance in diet and physical activity experience other health effects compared to a control group.

7. To search for biomarkers that can identify people at risk of increasing weight post surgery

Expected weight loss after GBP is 60-80% of the overweight. GBP is effective therapy against the obesity-related disorders, including T2DM. Some subjects start gaining weight within 12-18 months after surgery. Weight gain may again increase the risk for developing obesity-related disorders. Previous studies have found a link between vitamin D deficiencies and T2DM. Vitamin D levels will be monitored during the intervention. Studies have shown that patients who underwent GBP experienced a dramatic improvement in quality of life(QOL). After reaching maximum weight loss, many will slowly gain weight. For some people that means a decrease in QOL. In order to prevent weight gain it may be useful to provide additional follow-ups. Participants are randomised into two groups: Group A will receive extra guidance and follow-up, while Group B will continue with the existing scheme. Participants in Group A will over the next 2 yrs take part in frequent meetings. To assess dietary habits, physical activity patterns and QOL, food diaries, physical activity questionnaires and QOL questionnaires are used. Anthropometric and blood pressure measurements will be taken and blood samples will be collected at regular time intervals before and during the study. The results will be used to validate the effect of extra guidance, and to decide if this treatment shall be offered to all of our patients.

Inclusion Criteria:

• Patients undergoing gastric bypass surgery at OUH in the period January 2006 to June 2009 (recruited 24 ± 9 months following surgery)
• Willingness to participate at regular meetings at OUH

Exclusion Criteria:

• Patients who have experienced serious complications due to the bariatric surgery
• Patients who do not understand Norwegian
• Immobile patients