The metabolic effects of a high fructose versus a high glucose diet in healthy overweight men

Abstract

This study assessed the effects of high glucose and fructose intakes, both at energy balance and with overfeeding, on liver and muscle lipid contents and other metabolic parameters.32 healthy, centrally overweight men (age 34 yrs and BMI 29.4kg/m2) were randomised to 2 periods each of 2 weeks of either a high fructose or high glucose intake (25% energy). Groups were well matched at study entry. In the first 2 weeks, isoenergetic status was maintained by providing all foodstuffs, followed by a 6 week washout. The second 2 week period was an ad libitum overfeeding period. Period Fructose Glucose Sig between groups Mean SD Mean SD Weight (kg) Isoenergetic −0.26 0.9 −0.12 0.7 0.62 Overfeeding 1.03* 1.4 0.57 * 1.0 0.29 Hepatic lipid (%) Isoenergetic 0.30 2.2 −0.05 2.1 0.65 Overfeeding 1.70* 2.6 2.05* 2.9 0.73 ALT (U/L) Isoenergetic −4.0 7.9 −2.9 6.5 0.67 Overfeeding *5.8 8.7 4.1 9.8 0.62 Triglyceride (mg/dL) Isoenergetic −6.1 35.1 11.4 61.4 0.35 Overfeeding 31.6 70.2 28.9** 35.1 0.91 Absolute changes during each 2 week period =p<0.05, =p<0.01 compared to that group's baseline There were no changes during the isoenergetic period and similar changes in each group during overfeeding. There were no inter‐group differences in intramyocellular lipid, systemic or hepatic insulin resistance or haemodynamic parameters. Changes during the overfeeding period were strongly associated with weight changes. Hence these were an energy, as opposed to a nutrient, specific effect. There was no evidence for specific, potentially deleterious effects of fructose compared to glucose.Clinical trials registry: NCT01050140Financial support: CORE charity UK