Reference: Schwingshackl, L., et al., Olive oil in the prevention and management of type 2 diabetes mellitus: a systematic review and meta-analysis of cohort studies and intervention trials. Nutr Diabetes, 2017. 7(4): p. e262.
One-sentence summary: High olive oil intake was associated with a decreased risk of T2D and improved glucose metabolism in persons with T2D.
Study type: A systematic review and meta-analysis of 4 cohort studies and 29 RCTs on olive oil, T2D and glycemic control.
Diet: Diets containing olive oil (any type).
Outcomes measured: T2D risk and glycemic control (HbA1c and fasting plasma glucose).
Population: 22 studies in Europe, 8 studies in North America, 2 studies in Australia/New Zealand and 1 study in Asia. In the RCTs, only persons with T2D were included.
2. Glycemic control
b. Fasting plasma glucose
Quality assessment: The quality of the meta-analysis was rated using the Nutri-Grade system and was low for T2D risk and moderate for glycemic control (HbA1c and fasting glucose).
The bottom line: Olive oil reduced T2D risk and improved measures of glycemic control in people with T2D, at clinically significant levels. Since improvements in these outcomes have previously been described in individuals adhering to a Mediterranean diet, olive oil may be an important mediating factor in this dietary pattern.
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