Submitted to: Journal of Clinical Endocrinology and Metabolism
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/25/2008
Publication Date: 4/3/2008
Citation: Swarbrick, M.M., Stanhope, K.L., Elliott, S.S., Graham, J.L., Krauss, R.M., Christiansen, M.P., Griffen, S.C., Keim, N.L., Havel, P.J. 2008. Consumption of Fructose- But not Glucose-Sweetened Beverages for 10 Weeks Increases Postprandial Triglyceride and Apolipoprotein B Concentrations in Overweight/Obese Women. Journal of Clinical Endocrinology and Metabolism. 100:947-952, 2008. Interpretive Summary: Fructose is a simple sugar that is a component part of common sweeteners such as table sugar and syrups, including high fructose corn syrup. The amount of fructose consumed in the United States has increased in recent years, along with the increase in obesity and other diseases associated with obesity. We studied the effect of consuming a large quantity of fructose, in the form of a sweetened beverage for 10 weeks on blood glucose and blood lipid levels in older, post-menopausal women who were also overweight. We found that high levels of dietary fructose were associated with increases in fasting blood glucose, decreases in leptin (a hormone that affects hunger and energy metabolism), and marked increases in the circulating levels of blood lipids, particularly the triglycerides and the protein that is commonly associated with cholesterol. These changes suggest that consuming fructose-sweetened beverages in large amounts on a regular basis may increase the risk of cardiovascular disease.
Technical Abstract: Fructose consumption in the U.S. has increased over the past three decades. During this time, obesity, insulin resistance and the metabolic syndrome have increased in prevalence. While fructose- rich diets promote insulin resistance and hypertriglyceridemia in animals, there are insufficient data regarding the long-term effects of fructose consumption in humans. The objective of this study was to investigate and compare the metabolic/endocrine effects of long-term (10 week) consumption of fructose- or glucose-sweetened beverages in humans. Following a four-week weight-maintaining complex carbohydrate diet, subjects were fed an isocaloric diet, which included a fructose- or glucose-sweetened beverage with each meal, for ten weeks. Intervention diets provided 15% of energy from protein, 30% from fat, and 55% from carbohydrate (30% complex carbohydrate, 25% glucose or fructose). Eleven overweight to obese (BMI range 26-35 kg/m2) post-menopausal women were studied in a controlled metabolic setting. Main outcome measures included fasting and postprandial glucose, insulin, leptin, triglyceride, and apolipoprotein-B concentrations. Fructose consumption increased fasting glucose concentrations (4.6 ± 0.1 mmol/l at baseline vs. 4.9 ± 0.1 at 2 and 10 weeks, p<0.001) and decreased meal-associated glucose and insulin, and diurnal leptin excursions. At 10 weeks, subjects consuming fructose-, but not glucose-sweetened beverages, exhibited marked and prolonged postprandial hypertriglyceridemia and increased fasting apolipoprotein-B concentrations (p<0.05). The area under the curve for triglycerides was increased by 141% at 10 weeks (p<0.05). Consuming fructose- but not glucose-sweetened beverages increases circulating postprandial triglyceride and apolipoprotein-B concentrations in humans, suggesting that long-term consumption of diets high in fructose may increase the risk of cardiovascular disease.