Effects of Dietary Fructose Restriction on Liver Fat, De Novo Lipogenesis, and Insulin Kinetics in Children With Obesity.
Level 4 - case-series / case-control
Single-arm uncontrolled before-and-after interventional study
PubMed 28579536 · doi:10.1053/j.gastro.2017.05.043
What was done
A single-arm interventional study evaluated 41 Latino and African American children with obesity (aged 9–18 years) with habitual high sugar consumption (fructose >50 g/d). Participants were provided all meals for 9 days with an isocaloric diet matching baseline energy and macronutrient distribution, substituting starch for sugar to achieve a fructose content of 4% of total kilocalories. Liver fat, visceral adipose tissue (VAT), and subcutaneous fat were measured by magnetic resonance spectroscopy and imaging at baseline and day 10. Fractional de novo lipogenesis (DNL) area under the curve was measured using stable isotope tracers and gas chromatography/mass spectrometry. Insulin kinetics were calculated from oral glucose tolerance tests. Paired analyses compared within-subject changes from day 0 to day 10.
What was found
After 9 days of isocaloric fructose restriction: - Liver fat decreased from a median of 7.2% (IQR, 2.5%–14.8%) to 3.8% (IQR, 1.7%–15.5%) (P < .001). - VAT decreased from a median of 123 cm³ (IQR, 85–145 cm³) to 110 cm³ (IQR, 84–134 cm³) (P < .001). - Fractional DNL area under the curve decreased from 68% (IQR, 46%–83%) to 26% (IQR, 16%–37%) (P < .001). - Insulin kinetics improved (P < .001). - Changes occurred irrespective of baseline liver fat.
Why it matters
This study provides evidence that isocaloric substitution of starch for dietary fructose can rapidly reduce hepatic de novo lipogenesis, hepatic steatosis, and visceral fat in children with obesity without requiring weight loss or caloric restriction.
Limits
The study lacked a randomized control group receiving an unchanged or standard control diet. The intervention was very short (9 days), leaving long-term sustainability and outcomes unknown. The cohort was restricted to Latino and African American children with high baseline sugar intake, limiting generalizability to other populations.
Cited by
- supports Studies at UCSF showed that eating real food reduces insulin, fatty liver, uric acid, and ALT in nine days.