soft drinks and diabetes

Soft Drinks and Fruit Drinks Linked to Diabetes Risk in African American Women CME
News Author: Laurie Barclay, MD
CME Author: Charles Vega, MD
Disclosures
Release Date: July 30, 2008;
Charles Vega, MD
Disclosure: Charles Vega, MD, has disclosed an advisor/consultant relationship to Novartis, Inc.

Brande Nicole Martin
Disclosure: Brande Nicole Martin has disclosed no relevant financial information.


July 30, 2008 — Regular intake of sugar-sweetened soft drinks and fruit drinks is associated with an increased risk for type 2 diabetes in African American women, according to the results of a prospective follow-up study reported in the July 28 issue of the Archives of Internal Medicine.
"Type 2 diabetes mellitus is an increasingly serious health problem among African American women," write Julie R. Palmer, ScD, from Slone Epidemiology Center, Boston University in Massachusetts, and colleagues. "Consumption of sugar-sweetened drinks was associated with an increased risk of diabetes in 2 studies but not in a third; however, to our knowledge, no data are available on African Americans regarding this issue. Our objective was to examine the association between consumption of sugar-sweetened beverages, weight gain, and incidence of type 2 diabetes mellitus in African American women."
Since 1995, this study has observed 59,000 African American women, who reported on food and beverage consumption in 1995 and 2001 and completed biennial follow-up questionnaires to determine new diagnoses of type 2 diabetes. The present analyses involved data from 43,960 women who were free from diabetes at baseline and who provided complete dietary and weight information. The primary endpoint was the incidence of type 2 diabetes mellitus.
During 338,884 person-years of follow-up, 2713 incident cases of type 2 diabetes mellitus were identified. Higher intake of both sugar-sweetened soft drinks and fruit drinks was associated with a higher incidence of type 2 diabetes mellitus. The incidence rate ratio for 2 or more soft drinks per day was 1.24 (95% confidence interval [CI], 1.06 - 1.45), after adjustment for dietary factors and other confounding variables. The comparable incidence rate ratio for fruit drinks was 1.31 (95% CI, 1.13 - 1.52).
Although the association of diabetes with soft drink intake was almost entirely mediated by body mass index, the association with fruit drink consumption was independent of body mass index.
"Regular consumption of sugar-sweetened soft drinks and fruit drinks is associated with an increased risk of type 2 diabetes mellitus in African American women," the study authors write. "While there has been increasing public awareness of the adverse health effects of soft drinks, little attention has been given to fruit drinks, which are often marketed as a healthier alternative to soft drinks."
Limitations of this study include beverage consumption data collected at baseline, creating possible misclassification of exposure, and incident cases of type 2 diabetes based on self-report.
"Consumption of fruit drinks conveyed as high an increase in risk as did consumption of soft drinks," the study authors conclude. "The public should be made aware that these drinks are not a healthy alternative to soft drinks with regard to risk of type 2 diabetes."
In an accompanying editorial, Mark N. Feinglos, MD, CM, and Susan E. Totten, RD, from Duke University Medical Center in Durham, North Carolina, note that the greatest increase in weight was seen in those women who drank the most soft drinks.
"The critical issue in the development of diabetes is total caloric intake and subsequent weight gain rather than individual macronutrient composition, [but] modification of specific macronutrients might make it easier to decrease total calories," Drs. Feinglos and Totten write. "Until we have more information, we have to assume that calories trump everything else, and that our number 1 goal for the reduction of new cases of type 2 DM [diabetes mellitus] should be to reduce the intake of high-energy, low-benefit foods, particularly in young members of the most vulnerable populations."
The National Cancer Institute and the National Institute of Diabetes and Digestive and Kidney Diseases supported this study. Dr. Palmer has obtained funding. Another study author has received industry support from McNeil Consumer Healthcare and Boehringer Ingelheim.
Drs. Feinglos and Totten have disclosed no financial relationships.
Arch Intern Med. 2008;168:1485-1486, 1487-1492.
Clinical Context
High-fructose corn syrup is the main sweetener in sweetened soft drinks in the United States, and manufacturers may prefer this sweetener in a variety of foods because it is cheaper than sucrose while also offering a longer shelf life. An editorial by Feinglos and Totten reviews the effect of consumption of high-fructose corn syrup on health. Currently, high-fructose corn syrup accounts for 10% of the average total daily energy intake in the United States. Most consumption of high-fructose corn syrup is from soft drinks, and it appears that imbibing more soft drinks does not help to reduce appetite for more energy intake. However, there is conflicting evidence whether consumption of refined carbohydrates can contribute to an increased risk for type 2 diabetes when the total caloric intake remains stable.
The current study examines how consumption of both soft drinks and fruit drinks affects the risk for incident type 2 diabetes in African American women, a high-risk group for this disease.
Study Highlights
• Study data were drawn from an ongoing study of African American women, which began in 1995.
• 59,000 women between the ages of 21 and 69 years were included in the study cohort.
• A baseline questionnaire examined medical history and health habits. Only women who were at least 30 years old at the end of follow-up and did not report a history of diabetes, gestational diabetes, or cardiovascular disease were included in the current analysis.
• Incident type 2 diabetes was assessed via a participant self-report every 2 years during 5 cycles of follow-up. In a separate analysis, self-report of diabetes was found to be accurate in 94% of cases.
• The 68-item short-form Block-National Cancer Institute food frequency questionnaire was used to measure subjects' dietary habits.
• The main outcome of the study was the effect of soft drink (excluding diet soda) and juice drink (excluding orange juice and grapefruit juice) consumption on the risk for incident type 2 diabetes. This outcome was adjusted for potential confounders, including age, family history, physical activity, anthropometric factors, and other dietary habits.
• 43,960 women had data for analysis.
• 17% of participants reported drinking at least 1 sugar-sweetened soft drink per day, and 32% consumed at least 1 sweetened fruit drink per day.
• Intake of sugar-sweetened soft drinks was inversely related to age, physical activity, and years of education, and cereal fiber intake. Soft-drink consumption was positively related to body mass index, cigarette smoking, total energy intake, and consumption of processed meats. Consumption of fruit drinks was positively associated with physical activity and a low-glycemic index diet.
• 2713 cases of type 2 diabetes were diagnosed during 10 years of follow-up.
• Increased consumption of soft drinks was associated with higher weight gain during follow-up, whereas reduced consumption of soft drinks was associated with weight loss. The relationship between juice drink consumption and weight change was less robust.
• Consumption of 2 or more soft drinks per day was associated with an increased risk for incident diabetes (incidence rate ratio, 1.24).
• Consumption of 2 or more fruit drinks per day was also associated with an increased risk for incident diabetes (incidence rate ratio, 1.31).
• Consumption of orange or grapefruit juice was not associated with an increased risk for incident diabetes.
• The effect of soft drinks on the risk for diabetes appeared to be mediated by body mass index, but the effects of fruit juice in increasing the risk for diabetes were unrelated to body mass index.
• Soft drinks were associated with an increased risk for diabetes regardless of baseline age or body mass index.
Pearls for Practice
• High-fructose corn syrup is cheaper and has a longer shelf life vs sucrose. It accounts for 10% of the average daily energy intake in the United States, but it is unclear if consumption of refined carbohydrates independently increases the risk for type 2 diabetes.
• In the current study, both soft drink and fruit drink consumption were associated with a higher risk for incident type 2 diabetes in a cohort of African American women.