According to data from lab mice, supplementing a high fat diet with resveratrol reduced weight gain by about 40% compared with control mice fed the high fat diet only.
Professor Min Du and his co-workers demonstrated that mice fed a diet containing 0.1% resveratrol were able to change their excess white fat into the active, energy-burning ‘beige’ fat.
The researchers also showed that an enzyme called AMPK, which regulates the body’s energy metabolism, stimulates this transition of white fat into the brown-like fat.
“We provide evidence that resveratrol induces the formation of brown-like adipocytes in mouse [white adipose tissue in the groin] by increasing the expression of genes specific to brown adipocytes and stimulating fatty acid oxidation, which appeared to be primarily mediated by AMPK-alpha1,” wrote the researchers in the International Journal of Obesity.
“These data demonstrate, in addition to the inhibition of adipogenesis and stimulation of lipolysis, a novel browning role of resveratrol in white adipose tissue, which contributes to the beneficial effects of resveratrol in metabolism.
“Moreover, it extends our knowledge on dietary polyphenols and beige adipogenesis and provides new strategies for the prevention and treatment of obesity and related diseases.”
Types of fat
Until recently, researchers had always assumed there were only two types of fat; white fat where lipids are stored as energy and brown fat that burns lipids to produce heat, said Dr Du. But then scientists discovered so-called beige fat, which is in between white and brown fat.
“Resveratrol can enhance this conversion of white fat to beige fat and, when you have high rates of browning, it can partially prevent obesity,” he said.
Du said white fat is protective when it’s healthy. But too much leads to imbalance and disease.
“The current theory is that when we eat excessively, the extra lipids are stored in white fat. With obesity, the fat cells enlarge to a point where they’re saturated and can’t uptake more lipids,” he said. “As the fat cells become overloaded and die, they release toxins and cause inflammation leading to health problems like insulin resistance and diabetes.
“Polyphenols like resveratrol are good as they enhance the oxidation of fat so it won’t be overloaded. The excess is burned off as heat,” he said.
Resveratrol or other polyphenols, too?
Dr Du said that they used resveratrol as a representative for all polyphenols, and that while many researchers are using the pure compound itis the total polyphenolic content of fruit like blueberries, strawberries, and grapes that is more important.
“Polyphenols in fruit, including resveratrol, increase gene expression that enhances the oxidation of dietary fats so the body won’t be overloaded,” explained Dr Du. “They convert white fat into beige fat that burns lipids off as heat – helping to keep the body in balance and prevent obesity and metabolic dysfunction.”
The dose used in the mouse study was equivalent to about 12 ounces of fruit, or two to three servings per day.
The study was funded by the National Institutes of Health, the National Natural Science Foundation of China and an Emerging Research Issues Internal Competitive Grant from the WSU College of Agriculture, Human and Natural Resource Sciences.
Resveratrol
The study adds to an ever growing body of science supporting the potential benefits of resveratrol.
Interest in the polyphenol exploded in 2003 when research from David Sinclair and his team from Harvard reported that resveratrol was able to increase the lifespan of yeast cells. The research, published in Nature, was greeted with international media fanfare and ignited flames of hope for an anti-ageing pill.
According to Sinclair’s findings, resveratrol could activate a gene called sirtuin1 (Sirt1 – the yeast equivalent was Sir2), which is also activated during calorie restriction in various species, including monkeys.
Other studies with only resveratrol have reported anti-cancer effects, anti-inflammatory effects, cardiovascular benefits, anti-diabetes potential, energy endurance enhancement, and protection against Alzheimer’s.
Source: International Journal of Obesity
Volume 39, Pages 967–976; doi:10.1038/ijo.2015.23
“Resveratrol induces brown-like adipocyte formation in white fat through activation of AMP-activated protein kinase (AMPK) α1”
Authors: S. Wang, X. Liang, Q. Yang, et al.