Having sufficient brown fat could help protect against obesity and diabetes, new research shows.

Brown fat acts as an energy store in the body, but easily releases the energy to generate heat when exposed to cool temperatures. Recent research has revealed that brown fat can also remove branched chain amino acids (BCAAs) from the blood. In small quantities BCAAs can increase muscle mass and maintain good health, but in large quantities they are linked to obesity and diabetes.

The study identified that participants with a smaller proportion of brown fat were less able to clear excess BCAAs from their bloodstream, which could lead to the development of diabetes and obesity. It also revealed that a newly discovered protein, SLC25A44, was responsible for controlling the uptake rate of BCAAs into the mitochondria of brown fat cells. This enables the BCAAs to be converted into energy and heat.

The study explains how BCAA supplements can be beneficial to people with sufficient brown fat, but detrimental to people who lack brown fat. The discovery of the SLC25A44 protein gives a possible therapeutic target for preventing diabetes and obesity. Peoples stores of brown fat decline as they age, which could provide an explanation to age related weight gain. Slim people and people with lower blood sugar levels have higher levels of brown fat.

The researchers next aim to investigate if factors such as temperature, drugs or spicy food can influence the uptake rate of BCAAs. There is evidence that this could reduce high blood sugar levels observed in both obese and diabetic patients.