Abstract

Context: The American Heart Association Nutrition Committee recommends women and men consume no more than 100 and 150 kcal of added sugar per day, respectively, whereas the Dietary Guidelines for Americans, 2010, suggests a maximal added sugar intake of 25% or less of total energy. Objective: To address this discrepancy, we compared the effects of consuming glucose, fructose, or high-fructose corn syrup (HFCS) at 25% of energy requirements (E) on risk factors for cardiovascular disease. Participants, Design and Setting, and Intervention: Forty-eight adults (aged 18–40 yr; body mass index 18–35 kg/m2) resided at the Clinical Research Center for 3.5 d of baseline testing while consuming energy-balanced diets containing 55% E complex carbohydrate. For 12 outpatient days, they consumed usual ad libitum diets along with three servings per day of glucose, fructose, or HFCS-sweetened beverages (n = 16/group), which provided 25% E requirements. Subjects then consumed energy-balanced diets containing 25% E sugar-sweetened beverages/30% E complex carbohydrate during 3.5 d of inpatient intervention testing. Main Outcome Measures: Twenty-four-hour triglyceride area under the curve, fasting plasma low-density lipoprotein (LDL), and apolipoprotein B (apoB) concentrations were measured. Results: Twenty-four-hour triglyceride area under the curve was increased compared with baseline during consumption of fructose (+4.7 ± 1.2 mmol/liter × 24 h, P = 0.0032) and HFCS (+1.8 ± 1.4 mmol/liter × 24 h, P = 0.035) but not glucose (−1.9 ± 0.9 mmol/liter × 24 h, P = 0.14). Fasting LDL and apoB concentrations were increased during consumption of fructose (LDL: +0.29 ± 0.082 mmol/liter, P = 0.0023; apoB: +0.093 ± 0.022 g/liter, P = 0.0005) and HFCS (LDL: +0.42 ± 0.11 mmol/liter, P < 0.0001; apoB: +0.12 ± 0.031 g/liter, P < 0.0001) but not glucose (LDL: +0.012 ± 0.071 mmol/liter, P = 0.86; apoB: +0.0097 ± 0.019 g/liter, P = 0.90). Conclusions: Consumption of HFCS-sweetened beverages for 2 wk at 25% E increased risk factors for cardiovascular disease comparably with fructose and more than glucose in young adults.

In epidemiological studies, consumption of sugar and/or sugar-sweetened beverages has been linked to the presence of unfavorable lipid levels (1–5), insulin resistance (6, 7), fatty liver (8, 9), type 2 diabetes (10–12), cardiovascular disease (13), and metabolic syndrome (14). We have recently reported that consumption of fructose-sweetened beverages at 25% of energy requirements (E) increased visceral adipose deposition and de novo lipogenesis, produced dyslipidemia, and decreased glucose tolerance/insulin sensitivity in older, overweight/obese men and women, whereas consumption of glucose-sweetened beverages did not (15). Because the commonly consumed sugars, sucrose and high-fructose corn syrup (HFCS), are composed of 50–55% fructose, these results provide a potential mechanistic explanation for the associations between sugar consumption and metabolic disease. However, the adverse metabolic effects of fructose consumption observed in the older, overweight/obese population (15) may not occur in a younger, leaner population.

Authors of three recent reviews have concluded that long-term sugar intakes as high as 25–50% E have no adverse effects with respect to components of metabolic syndrome (16) and that fructose consumption up to 140 g/d does not result in biologically relevant increases of fasting or postprandial triglycerides (TG) in healthy, normal-weight (17), or overweight or obese (18) humans. These reviews (16, 17) are cited in the Report of the Dietary Guidelines Advisory Committee on the Dietary Guidelines for Americans 2010, released June of 2010, in which a maximal intake level of 25% or less of total energy from added sugars is suggested (19). However, in August of 2009, the American Heart Association Nutrition Committee recommended that women consume no more than 100 kcal/d and men consume no more than 150 kcal/d of added sugar (20). This equates to differences between the two guidelines of 400 kcal/d for women consuming 2000 kcal/d and 525 kcal/d for men consuming 2500 kcal/d. To address this discrepancy, we compared the effects of consuming 25%E as glucose, fructose or HFCS for 2 weeks