Short Science, December 30, 2012

PUBLISHED : Sunday, 30 December, 2012, 12:00am
UPDATED : Sunday, 30 December, 2012, 7:12am

Study casts doubt on green-tea weight loss

One of the key compounds in green tea is Epigallocatechin gallate, or EGCG, a potent antioxidant, which supporters say reduces fat gain and enhances fat-burning. But it is not found enough in a typical cup of green tea to have much effect, according to a report in The Cochrane Database of Systematic Reviews. The report analysed a dozen randomised controlled trials, each lasting at least three months, and found that regularly drinking green tea had no meaningful effect on weight loss in overweight adults. The researchers took blood samples and did extensive testing, all of which indicated that the green tea extract did not improve fat oxidation. NYT


BMI effective indicator of health problems

A study found that body mass index, a calculation involving the ratio of height to weight, works at least as well as other body measurements, and better than some, to predict health problems. Researchers said BMI and body fat percentage were the best predictors of raised blood pressure, while waist circumference and waist-to-height ratio were good predictors of elevated fasting glucose and reduced HDL cholesterol, otherwise known as "good cholesterol". Body fat percentage was a better marker for "bad cholesterol". NYT


2 cups of milk right balance for children

Cow's milk is the primary source of vitamin D for children, but dairy products can interfere with the absorption of iron. Now researchers have established that for most children, two cups a day achieves the right balance. A study by Canadian scientists, published online in the journal Pediatrics, found that two cups a day was enough to maintain sufficient vitamin D without affecting iron levels. NYT


Porpoise numbers down in Yangtze

A survey of endangered porpoises in the Yangtze River has yielded fewer sightings as intensive ship traffic threatens their existence. Based on sonar tracking results, researchers said a total of 91 finless porpoises, found only in China, were detected while travelling the 3,400 kilometres from Yichang to Shanghai, down sharply from 177 in 2006. The survey marked the most comprehensive study of the species since 2006. AFP