Sugar-Sweetened Beverages Raise Risk of Diabetes, Obesity in Women, Study Finds
Women who drink at least one serving of non-diet soda or fruit punch per day gain "much more weight" and have a "sharply elevated risk" of developing type 2 diabetes than women who drink less than one serving per month, according to a study published in the Journal of the American Medical Association, the Washington Post reports (Stein, Washington Post, 8/25). The NIH-funded study, which was conducted by researchers from the Harvard School of Public Health, Brigham and Women's Hospital and Boston Children's Hospital, analyzed 52,000 female nurses' health records and dietary habits from 1991-1999 (Burton/McKay, Wall Street Journal, 8/25).
The nurses who were studied ranged in age from their 20s to their 40s (Lee, Atlanta Journal-Constitution, 8/25). The report is part of the ongoing Nurses' Health Study II project, which includes 91,249 women and is designed to examine a wide variety of health issues (Washington Post, 8/25). Sweetened soft drinks are the largest single food source of calories for U.S. residents, contributing 7% of total calorie consumption, the Journal-Constitution reports (Atlanta Journal-Constitution, 8/25). The study focused on risks associated with drinks sweetened with either sugar or high-fructose corn syrup.
Researchers said that overall, after adjusting for possible contributing factors, women who had one or more drinks containing sugar or corn syrup per day were 83% more likely to develop diabetes than those who drank less than one serving per month (Washington Post, 8/25). According to the study, sugar-sweetened fruit punch is linked to a doubled risk of diabetes, while 100% fruit juice was not (Wall Street Journal, 8/25). Among the research subjects, there were 741 new cases of diabetes during the research period. Researchers said the risk of diabetes may increase because the sugars in sweetened drinks are quickly absorbed by the body, rapidly raising blood sugar levels and leading to insulin resistance (Atlanta Journal-Constitution, 8/25). Harvard researcher Walter Willett said the increased risk of diabetes probably stemmed from the "high amounts of sugar in the bloodstream [that] put an increased demand for insulin on the pancreas" (Washington Post, 8/25).
Nathanial Clark, a doctor and the American Diabetes Association's vice president for clinical affairs, said ADA does not single out any food or beverage as causing the disease, although he added that extra weight, rather than sugar consumption, can trigger diabetes in women. However, Clark also noted that the study's researchers "could not account for the increase in diabetes solely on weight gain." JoAnn Manson, chief of preventive medicine at Brigham and Women's Hospital and contributing author of the study, said that extra weight accounted for half of the increased risk of diabetes (Atlanta Journal-Constitution, 8/25). Lawrence Chan, a diabetes researcher at Baylor College of Medicine, said that the finding that 100% fruit juice -- which has nearly as many calories as soft drinks and fruit punch -- is not associated with diabetes is "interesting." He added, "It suggests the quality of sugar is important" (Berger, Houston Chronicle, 8/25). Researchers found that diet sodas were linked to a "slight, nonsignificant increased risk" of diabetes (Wall Street Journal, 8/25).
Women who drank at least one serving of sweetened drinks per day gained an average of 17 pounds over the study period, compared with an increase of six pounds for women who drank less than one serving per month (Smith, Boston Globe, 8/25).
The women who gained the most weight increased their consumption of the drinks from one or fewer per week to one or more per day over an average of four years. This set of women gained an average of 10.3 pounds over that duration, compared with a weight gain of less than three pounds for women who drank one serving or less per week (Washington Post, 8/25). Researchers theorized that the weight gain occurred because sodas deliver a "bounty of calories" but do not sate drinkers' appetites and "may not cut down their consumption of calories from food" (Boston Globe, 8/25).
Although past studies have linked sugary drinks to obesity and diabetes, the new study is "by far the largest and best-designed and one of the first to examine the issue in adults," the Post reports. Although the study only involved women, researchers said they believed the increased risks would hold for men (Washington Post, 8/25).
The study's authors called for "public health strategies" that would decrease the level of sugar-sweetened beverage consumption, the Journal-Constitution reports. An editorial accompanying the study also called for the government to redefine guidelines for sugar consumption and support efforts to replace soda machines in schools (Atlanta Journal-Constitution, 8/25). Willett said, "The message is: Anyone who cares about their health or the health of their family would not consume these beverages. Parents who care about their children's health should not keep them at home" (Washington Post, 8/25).
Food and restaurant advocacy groups criticized the study's findings. Dan Mindus, a senior analyst with the Center for Consumer Freedom, said, "This is fizzy science to promote an anti-soda agenda that tries to scare Americans without the data to back it up. It's the typical hysterical rhetoric, without solid evidence, that indicates a biased agenda by nutritional Puritans" (Houston Chronicle, 8/25). Richard Adamson, vice president of the American Beverage Association, said, "It is inexplicable that the authors have chosen to focus solely on sugar-sweetened beverages in this way. Neither soft drinks nor fruit juice consumption nor sugar intake are listed by the National Institutes of Health, the American Diabetes Association or the majority of published medical literature as risk factors for type 2 diabetes." Adamson added, "This study provides no evidence to support the inflammatory allegation that sugar-sweetened beverages are a cause of type 2 diabetes" (Wall Street Journal, 8/25).
Adamson called the study's findings "scientifically unsound" and said researchers did not take into account other variables that could account for the heightened risk. He said women who drink a lot of sweetened drinks may just have generally unhealthy lifestyles. "If [researchers] would have adjusted for all the confounding factors, they would not have found any risk at all," Adamson said. Charles Baker, vice president for scientific affairs for the Sugar Association, added that the increased risk of diabetes found in the study was due to weight gain and not sugar intake. Baker said, "It's not about sugar. It's about calorie imbalance" (Washington Post, 8/25).
According to the Journal, the study did not "prove causation," but "the increase in diabetes risk was consistent across various categories of people." The researchers said they found heavy drinkers of sweetened soft drinks to be "less physically active, to smoke more and to have higher intake of total energy and lower intake of protein, alcohol, magnesium and cereal fiber." However, the researchers concluded that the "results remained similar" even when the effects of these and other such factors were removed (Wall Street Journal, 8/25). The study is available online.
ABCNews' "World News Tonight" on Tuesday reported on the study. The segment includes comments from Dr. Marion Nestle, chair of nutrition, food and public health studies at New York University, and Dr. Meir Stampher, chair of the Department of Epidemiology and Nutrition at the Harvard School of Public Health (McKenzie, "World News Tonight," ABCNews, 8/24).This is part of the California Healthline Daily Edition, a summary of health policy coverage from major news organizations. Sign up for an email subscription.