Increased levels of blood caffeine might curb body fat amount and type 2 diabetes risk: Study

A high blood caffeine level might curb the amount of body fat a person carries and their risk of type 2 diabetes, suggests research published in the open access journal BMJ Medicine. The researchers used Mendelian randomisation to find out what effect higher blood caffeine levels have on body fat and the long term risks of type 2 diabetes and major cardiovascular diseases-coronary artery disease, stroke, heart failure, and irregular heart rhythm (atrial fibrillation).

The researchers looked at the role of two common genetic variants of the CYP1A2 and AHR genes in nearly 10,000 people of predominantly European ancestry, who were taking part in 6 long term studies. The CYP1A2 and AHR genes are associated with the speed of caffeine metabolism in the body.

People who carry genetic variants associated with slower caffeine metabolism drink, on average, less coffee, yet have higher levels of caffeine in their blood than people who metabolise it quickly to reach or retain the levels required for its stimulant effects.

The results of the analysis showed that higher genetically predicted blood caffeine levels were associated with lower weight (BMI) and body fat. Higher genetically predicted blood caffeine levels were also associated with a lower risk of type 2 diabetes. The researchers then used Mendelian randomisation to further explore the extent to which any effect of caffeine on type 2 diabetes risk might principally be driven by the concurrent weight loss. The results showed that weight loss drove nearly half (43%) of the effect of caffeine on type 2 diabetes risk.

Reference:

Appraisal of the causal effect of plasma caffeine on adiposity, type 2 diabetes, and cardiovascular disease: two sample mendelian randomisation study,BMJ Medicine,doi 10.1136/bmjmed-2022-000335