This article is more than 5 years old. Information may no longer be current.
Short-term high-fructose diet may yield higher post-meal liver fat, de novo lipogenesis
Among healthy men on a weight maintenance diet, the short-term consumption of a high-fructose diet may yield increased levels of hepatic post-meal de novo lipogenesis and liver fat, according to recent findings.
In the study, Jean-Marc Schwarz, PhD, of Touro University, and colleagues evaluated eight healthy men aged 18 to 65 years, with BMI less than 30 kg/m2. The participants, who were recruited from the local community, were studied in a controlled inpatient environment at the University of California, San Francisco Clinical and Translational Science Institute Clinical Research Center for 18 days.
During the study, participants consumed weight-maintaining diets with fixed levels of protein (15% of total calories), fat (35%) and carbohydrates (50%). Over the consecutive 9 day period, the participants consumed diets high in fructose (20%-25% of energy intake through a fructose-containing drink) and a diet with the equivalent number of calories in the form of complex carbohydrates instead of fructose. The first four participants followed the complex carbohydrate diet for the first 9 days and then switched to the high-fructose diet; the second group consumed the diets in the reverse order.
The researchers used stable isotope tracers to assess fractional hepatic de novo lipogenesis and endogenous glucose production and its inhibition during a euglycemic-hyperinsulinemic clamp. Measurements of liver fat were taken using magnetic resonance spectroscopy.
Participants were weighed each morning, and the whole body fat and lean body mass were measured at baseline and at the conclusion of each diet period using DXA.
The researchers found that regardless of the sequence in which the participants followed the diets, the high-fructose diet was linked to higher average de novo lipogenesis (P = .001) and liver fat (P = .016) in all participants. There was no significant difference in fasting measurements of endogenous glucose production or insulin-mediated glucose disposal, but the high-fructose diet yielded higher endogenous glucose production during the hyperinsulinemic clamp (P = .013), indicating diminished inhibition of endogenous glucose production.
According to the researchers, these findings are the first to demonstrate that even when energy balance is neutral, the quality of carbohydrates consumed can have an impact on the metabolization of fat by the liver.
“On the other hand, we saw no significant effects of a high-fructose diet on fasting [de novo lipogenesis], lipids, glucose or insulin; or on insulin-mediated glucose uptake,” the researchers wrote. – by Jennifer Byrne
Disclosure: The researchers report no relevant financial disclosures.