Polyphenols may strengthen bones and inhibit fat tissue formation

According to new findings presented at Experimental Biology 2011, a gathering of six scientific societies, green tea polyphenols may work synergistically with tai chi to enhance bone strength.

Green tea polyphenols at a daily dose equivalent to 4 to 6 cups of green tea, combined with tai chi was associated with a significant reduction in levels of markers of oxidative stress, according to findings presented at the EB2011 event in Washington DC yesterday by Dr Chwan-Li (Leslie) Shen from Laura W. Bush Institute for Women's Health at the Texas Tech University Health Sciences Center.

When green tea (500 milligrams per day) was consumed independently (no tai chi) the Texas-based researcher said that green tea polyphenols were associated with ‘enhanced markers of bone health by 3 and 6 months, and a similar effect was found for muscle strength at the 6-month time point’​.

The study involved 171 postmenopausal women with an average age of 57 and weak bones but no osteoporosis receiving placebo, green tea polyphenols, tai chi, or a combination of green tea and tai chi for six months.

The data indicates a "favorable effect of modest green tea consumption on bone remodeling in this pre-osteoporotic population"​, said the researchers.

Green tea benefits​

The results add to an ever-growing body of science linking consumption to a wide range of health benefits, including lower risk of certain cancers, weight loss, heart health, and protection against Alzheimer's. It is not the first time that green tea consumption has been linked to bone health.

Green tea contains between 30 and 40 per cent of water-extractable polyphenols, while black tea (green tea that has been oxidized by fermentation) contains between 3 and 10 per cent.

The four primary polyphenols found in fresh tealeaves are epigallocatechin gallate (EGCG), epigallocatechin, epicatechin gallate, and epicatechin.

The study lasted for 6 months, during which time blood and urine samples were collected and muscle strength assessed.

Blueberries vs fat tissue​

Also presented at this year’s meeting were preliminary data from Shiwani Moghe, MS, a graduate student from Texas Woman's University (TWU), which indicated that polyphenols from blueberry may suppress the differentiation of adipocytes – a process key to the formation of fat cells (adipocytes) that specialize in the synthesis and storage of fat.

According to her findings, also presented at EB2011 yesterday, Moghe’s results suggest that polyphenols from blueberries may inhibit obesity at a molecular stage.

Using tissue cultures taken from mice, the Texas-based researcher reported that blueberry compounds showed a dose-dependent suppression of adipocyte differentiation.

Specifically, the highest dose of blueberry polyphenols yielded a 73 percent decrease in lipids; the lowest dose showed a 27 percent decrease, she said.

"We still need to test this dose in humans, to make sure there are no adverse effects, and to see if the doses are as effective,”​ said Moghe. “This is a burgeoning area of research. Determining the best dose for humans will be important. The promise is there for blueberries to help reduce adipose tissue from forming in the body."​