含糖运动饮料对健康无益

Children who practice healthy lifestyle habits such as eating fruits and vegetables and engaging in physical activity may be negatively impacting their health because they tend to consume large amounts of flavored and sports beverages（饮料） containing sugar, according to research at The Michael & Susan Dell Center for Healthy Living at The University of Texas Health Science Center at Houston (UTHealth). "Children and parents associate these drinks with a healthy lifestyle despite their increased amount of sugar and lack of nutritional value," said Nalini Ranjit, Ph.D., principal investigator and assistant professor of behavioral sciences at the UTHealth School of Public Health. The study will be published in the October issue of Pediatrics.

Researchers examined the association between sugar-sweetened beverage consumption, unhealthy and healthy foods and physical activity levels of 8th and 11th grade Texas students to determine the relationship between beverage consumption and other behaviors. Sugar-sweetened beverages are drinks that contain added caloric（热量的） sweeteners such as sugar or high-fructose（果糖） corn syrup（玉米糖浆） , including a large variety of carbonated and noncarbonated drinks but excluding 100 percent fruit juice.

Flavored or sports beverage drink consumption increased with levels of healthy food consumption and physical activity when compared to high soda consumption, which was associated with lower levels of these healthy behaviors.

"Sports drinks have been successfully marketed as beverages consistent with a healthy lifestyle, which has set them apart from sodas," said Ranjit, "However they have minimal fruit juice and contain unnecessary calories." Study results suggest there is a popular misperception（错误知觉） of flavored and sports beverages being consistent with a healthy lifestyle, despite their sugary content.

Researchers in the study found that 28 percent of Texas children are consuming sugar-sweetened beverages three or more times a day. Among boys, the average daily consumption of soda increased from 8th to 11th grade while consumption of non-carbonated flavored and sports beverages remained steady. Soda consumption in girls remained steady from 8th to 11th grade and consumption of non-carbonated flavored and sports beverages declined substantially. Of the ethnicities（种族划分） of the children involved in the study, researchers found black children had lower soda consumption but considerably higher flavored and sports beverage consumption compared to Hispanic or white children.

Nearly 17 percent of children and adolescents ages 2 to 19 in the United States are in the 95 percentile of the BMI-for-age growth charts, according to the Centers for Disease Control and Prevention. There is widespread consensus that the increasing consumption of sugar-sweetened beverages is associated with high levels of obesity（肥胖） nationwide, according to the study.

"High levels of consumption of these beverages has the potential to increase weight gain," said Ranjit, "Drinking just one can of soda or other sugary beverage a day could lead to more than a 10-pound weight gain in a year." Nutritionists at UTHealth also caution that children should have no more than one glass of fruit juice, even 100 percent fruit juice, a day, because of the high calories. Sports drinks should be reserved only for extreme exercise. Otherwise, children should drink water to replenish（补充） lost fluids, they say, and whole fruit is a better nutritional choice than fruit juice.

Ranjit recommends adolescents and their parents educate themselves on the sugar content of flavored and sports beverages. "Consuming large amounts of flavored and sports beverages could undo the effects of all that exercise," said Ranjit. "Recognizing these misperceptions is important to obesity prevention efforts."