Plain language summary
Cardiovascular disease, diabetes and obesity have increased in recent decades and some studies have established a direct link between insulin resistance (IR) and these conditions. Currently, the relationship between sugar intake and the risk of obesity and diabetes remains controversial. However, some studies involving overweight or obese participants without diabetes concluded that increasing fructose intake under certain conditions lead to the development of hepatic IR in adults. The primary objective of this randomised controlled study was to determine whether decreasing the consumption of foods with high amounts of fructose, independent of a reduction in calorie intake, led to a decrease in IR after 24 weeks. 438 adults who were obese or overweight but not diabetic, took part in the 24-week study, one group ate a low fructose diet and the other a standard diet. The low fructose diet did not reduce IR but it reduced waist circumference and fasting blood glucose. The authors conclude that in overweight and obese non-diabetic primary care patients, a small decrease in the consumption of added fructose in a sustained manner may be enough to achieve metabolic benefits. New studies with larger number of patients are needed.
Abstract
The relationship between fructose intake and insulin resistance remains controversial. Our purpose was to determine whether a reduction in dietary fructose is effective in decreasing insulin resistance (HOMA2-IR). This field trial was conducted on 438 adults with overweight and obese status, without diabetes. A total of 121 patients in a low fructose diet (LFD) group and 118 in a standard diet (SD) group completed the 24-week study. Both diets were prescribed with 30-40% of energy intake restriction. There were no between-group differences in HOMA2-IR. However, larger decreases were seen in the LFD group in waist circumference (-7.0 vs. -4.8 = -2.2 cms, 95% CI: -3.7, -0.7) and fasting blood glucose -0.25 vs. -0.11 = -0.14 mmol/L, 95% CI: -0.028, -0.02). The percentage of reduction in calorie intake was similar. Only were differences observed in the % energy intake for some nutrients: total fructose (-2 vs. -0.6 = -1.4, 95% CI: -2.6, -0.3), MUFA (-1.7 vs. -0.4 = -1.3, 95% CI: -2.4, -0.2), protein (5.1 vs. 3.6 = 1.4, 95% CI: 0.1, 2.7). The decrease in fructose consumption originated mainly from the reduction in added fructose (-2.8 vs. -1.9 = -0.9, 95% CI: -1.6, -0.03). These results were corroborated after multivariate adjustments. The low fructose diet did not reduce insulin resistance. However, it reduced waist circumference and fasting blood glucose concentration, which suggests a decrease in hepatic insulin resistance.
Methodological quality
Jadad score
:
2
Allocation concealment
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No
