Surgical treatment for type 2 diabetes has been taken note especially in less obese or non obese patients. In Asian, the nuber of less obses or non obese patients with T2DM is greater than that of the obese.

We are trying to do a prospective observational study for the evaluation of the effect of duidenojejunal bypass and gastric bypass on the glycemoc control in those patients.

The selection criteria are type 2 diabetess, 20-60 years old, BMI 23-34 or 21-22 with viceral obesity, insulin use less than 10 years and the patients understanding the hypothesis of this study, risks, expecting effects and agreeing this study.

We are checking oral GTT, insulin level, C-peptide level, HbA1C, etc. with some anthropometric measurs preoperatively, postoperatively, at 3 month and 12 month.

We will compare the clinical factors at each time.

Inclusion Criteria:

• type 2 diabetes
• HbA1C > 7.0%
• BMI 23 - 34 or BMI 21-22 with viceral obesity
• insulin use less than 10 years
• uncerstanding the risks, hypothesis, expecting effects

Exclusion Criteria:

• type 1 diabetes
• C-peptide < 1.0ng/ml
• BMI < 21
• severe cardiovascular diseases or their history
• malignancy or history
• alcoholics, pituitary failrue
• history of severe ketosis, diabetic coma or precoma
• abnormal liver enzyme, over 3 fold of normal level
• liver cirrhosis or hepatitis
• serum creatinine > 2.0mg/dL
• glucocorticoids user
• diabetes due to other endocrine diseases
• pancreatic disease
• anti-GAD Ab (+)
• the incongruity for surgery