Guidance in Diet and Physical Activity for Prevention of Weight Gain After Gastric Bypass Surgery

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