In cold temperatures, brown adipose tissue (BAT) or brown fat generates heat to keep the body warm, and has significantly more mitochondria (subcellular organelles that help producing energy) than white adipose tissue. Thus, it can burn calories and produce heat by activating the mitochondrial uncoupling protein 1 (Ucp-1). The stimulation of the sympathetic nervous system (SNS) after exposure to cold, exercise, or calorie restriction induces white fat browning. BAT activation and fat browning are essential in the fight against cardiovascular conditions, as well as obesity.
A new study led by the Shibaura Institute of Technology, Japan, has discovered that the dietary administration of flavanols, chemical compounds with strong antioxidant and anti-inflammatory effects that can be found in cocoa, apples, grapeseed, and red wine, can also activate BAT and enhance browning of adipose tissue by activating the SNS. These findings show a direct connection between fat browning and flavanol consumption, which could help scientists develop new treatments for obesity-related disorders.
By administering both single and multiple doses of flavanols to mice, the researchers found that flavanols activate fat browning via the SNS, which secretes catecholamine neurotransmitters such as adrenaline and noradrenaline. The white fat cells of mice that were fed flavanols daily for two weeks eventually turned brown, exhibiting notable structural changes.
“Although the mechanism of adipose browning is not fully understood, it is possible that repeated administration of FLs may produce browning via catecholamines and its receptors,” explains study lead author Naomi Osakabe, a professor of Bioscience and Engineering at the Shibaura Institute. “Further studies will be required to understand how this process is induced by FL-rich foods.”
Previous findings have already proven the positive role of flavanols in improving glucose and insulin levels. According to Professor Osakabe and her colleagues, the results of this new study can significantly contribute to scientific advances in the prevention of lifestyle-related diseases, such as cardiovascular illness or obesity.
The study is published in the journal Nutrients.