Formerly, the investigators demonstrated in an uncontrolled proof-of principle study (NCT 01680926) that protein-rich meal replacement (PRMR) was successful in reducing daily insulin demand, HbA1c and weight in type 2 diabetes mellitus (T2DM) patients injecting >100 IE insulin/day. The aim of the present study was to investigate in a randomized-controlled trial if PRMR is also effective in T2DM patients treated with oral antidiabetic medication or insulin.

A second part of the study is an open-label registry for persons with type 2 diabetes, who will perform the lifestyle intervention with the stringent diet regime.

Type 2 diabetes mellitus (T2DM) patients had been randomized into two groups. During the 1st week the intervention group with stringent diet regime replaced 3 main meals by 50 g PRMR (Almased-Vitalkost, Almased Wellness GmbH, Bienenbüttel, Germany) each (=1100 kcal/day). In 2nd-4th week 2 meals were replaced and a protein-rich lunch was allowed. In 5th-12th week only dinner was replaced. The control group with moderate diet regime replaced breakfast and dinner for 4 weeks and then only dinner during the next 8 weeks. Clinical parameters were determined at the study center at baseline, after 4, 8 and 12 weeks. Primary endpoint was reduction of HbA1c, secondary endpoints reduction of weight and antidiabetic medication.

In the second part of the study type 2 diabetes patients are included in an open-label reistry and perform the lifestyle intervention with the stringent diet regime.

Inclusion Criteria:

• Type 2 diabetes mellitus
• HbA1c > 7,5%
• Body Mass Index (BMI) ≥ 27,5 kg/m2

Exclusion Criteria:

• acute infections
• severe diseased with hospital stay during the last 3 months
• chronic diseases
• chemotherapy or cortisone treatment
• weight loss of more than 2 kg per week during the last month
• smoking cessation during the last 3 months or planned
• weight-influencing medication
• pregnancy, breast-feeding or lack of contraception
• high-level physical activity of more than 1h per day
• incompatibility with components of the PRMR
• participation in an other study during the last 6 months

For the open-label registry, the only inclusion criterium is type 2 diabetes.

For the second part of the study, i.e. the open-label registry, 4000 subjects are anicipated.