Olive oil may help reduce type 2 diabetes risk
A study published in Nutrition & Diabetes suggests that for healthy adults olive oil consumption may lower their risk for developing type 2 diabetes.
A study published in Nutrition & Diabetes suggests that for healthy adults olive oil consumption may lower their risk for developing type 2 diabetes. In addition, daily olive oil ingestion may improve glucose metabolism in adults who already have type 2 diabetes.
The researchers analyzed data from four cohort studies and 29 randomized controlled trials conducted in Europe, North America, Australia/New Zealand, and Asia. Study duration varied between 5.7 and 22 years for cohort studies and between 2 weeks and 4.1 years for randomized controlled trials; mean ages ranged between 33 and 67. Randomized controlled trials were stratified by three types: olive oil vs. low-fat diet; olive oil vs. polyunsaturated fatty acid-rich oils, and olive oil vs. fish oil.
The researchers performed three types of meta-analyses to investigate any association between olive oil consumption and type 2 diabetes risk: high vs. low-intake meta-analysis, dose-response meta-analysis, and restricted cubic spline calculation for each study with more than three categories of exposure to examine for possible nonlinear associations.
In random-effects meta-analysis, the researchers found the combined association of the use of olive oil was inversely associated with a lower risk for type 2 diabetes. Compared with the lowest olive oil intake category, those in the highest olive oil intake category saw a 16% reduced risk for developing type 2 diabetes; however, researchers observed evidence of a nonlinear relationship. In the dose-response meta-analysis, researchers found that each 10-g daily increase in olive oil intake was associated with a 9% reduced risk. Risk for developing type 2 diabetes decreased by 13% with increasing olive oil consumption to 15–20 g per day; however, there was no observed benefit beyond this value, according to researchers.
In participants with type 2 diabetes, olive oil interventions resulted in a greater reduction in glycated hemoglobin (HbA1c) vs. controls. In subgroup analyses, the effect persisted only when compared with low-fat diets, according to researchers. There were no between-group differences for olive oil interventions vs. fish oil or polyunsaturated fatty acid-rich oils. In sensitivity analyses, olive oil consumption was associated with improvements in HbA1c and fasting plasma glucose in trials with a low risk for bias.
The researchers concluded that “in light of other benefits, especially reported for extra virgin olive oil as an integral part of a Mediterranean diet, this vegetable oil represents a suitable component of a balanced diet.”