Recent studies have found that up to 45 % of patients with type 1 diabetes have metabolic syndrome, a cluster of conditions (abdominal obesity, hypertension, dyslipidemia, insulin resistance) that increase the cardiovascular risk. The investigators have observed in previous studies a strong association between the adherence to a Mediterranean diet and the prevalence of metabolic syndrome on patients with metabolic syndrome. However, no intervention has been realized on this population and the current recommendations (low fat diet) differ from the Mediterranean diet. A nutritional intervention on the principles of the Mediterranean diet could therefore play a role in the treatment of the metabolic syndrome in Type 1 diabetes patients. The main objective of this study is to examine the impact of a nutritional intervention on the waist circumference after 6 months of an intervention group (Mediterranean diet) versus a control group (low fat diet).

Inclusion Criteria:

• Type 1 Diabetes for at least 12 months

• On intensive insulin therapy with multiple daily injections or on insulin pump

• Be overweight or obese (BMI≥25 kg/m2)

• Stable weight for at least 3 months

• If on medication for thyroid, hypertension or dislipidemia: stable doses in the last 3 months

• Presenting at least 3 of the 5 following criteria for metabolic syndrome:

  1. Waist circumference >102cm ♂ or >88cm ♀
  2. Triglycerides >1.7mmol/L or medication
  3. Cholesterol-HDL <1.0mmol/L ♂ or <1.3mmol/L ♀ or medication
  4. Blood pressure ≥130/85 mmHg or medication
  5. Estimated insulin resistance (eGDR <6.29)

Exclusion Criteria:

• Mental incapacity, refusal or linguistic barrier that could affect comprehension or cooperation with the study
• Ongoing pregnancy
• Diet corresponding to the criteria of a mediterranean diet (score≥27)
• Vegetarianism
• Major diabetes complications