The effects of a Mediterranean diet on people with type 2 diabetes Original paper

In this meta-analysis of randomized controlled trials, consuming a Mediterranean diet improved blood pressure and glycemic control in people with type 2 diabetes.

The effects of a Mediterranean diet in the context of type 2 diabetes (T2D).

The outcomes assessed were BMI, weight, waist circumference, blood lipids (total cholesterol, HDL-C, LDL-C, and triglycerides), blood pressure, fasting glucose, and HbA1c.

A total of 1,371 participants (ages 25–75) with T2D.

A meta-analysis of 7 randomized controlled trials was performed. Three studies were conducted in the United States and 1 study each was conducted in Israel, Italy, Iran, and Spain.

In 4 studies, the participants in the control group consumed their usual diet. In the other 3 studies, the participants consumed a high-carbohydrate, low-fat diet (50%–60% of calories from carbohydrate, ≤30% fat, 15%–20% protein). The duration of the intervention ranged from 6 months to 8.1 years.

Compared to the control diet, a Mediterranean diet reduced systolic blood pressure (−4.17 mmHg), diastolic blood pressure (−1.20 mmHg), HbA1c (−0.39%), fasting glucose (−15.12 mg/dL), BMI (−0.71), and waist circumference (−1.69 cm).

The reduction in systolic blood pressure was clinically significant, and the reduction in HbA1c was comparable to that of some antidiabetic drugs.

Two studies had a high risk of bias, and the rest had some concerns, which reduces our confidence in the results.