Sugar-to-starch exchange diet decreases liver fat in pediatric obesity
Isocaloric fructose restriction in children with obesity showed a decrease in liver fat, visceral fat and de novo lipogenesis and improved insulin kinetics after a 9-day diet, according to recently published data.
“The improvements in these outcome measures occurred irrespective of baseline liver fat content or weight change,” Jean-Marc Schwarz, PhD, from the Touro University, California, and colleagues wrote. “These short-term data support an intervention focusing on fructose restriction as an approach to both combat [nonalcoholic fatty liver disease] and improve insulin kinetics.”
The study comprised 41 children (26 girls; mean age, 13 years) of Latino or African-American ethnicity who had obesity but did not have diabetes and reported a regular high sugar intake. Twenty-five of the participants had elevated liver fat fraction of 5% or higher and 15 had liver fat fraction below 5%. Thirty-eight were paired for liver fat measurements and 40 for visceral adipose tissue and subcutaneous adipose tissue measurements.
The 9-day diet featured an isocaloric substitution of starch for most sugar. Daily intake during the diet included an average of 28 kilocalories/kg with a macronutrient profile of 51% carbohydrate, 16% protein and 33% fat. This decreased dietary sugar intake from 28% to 10% and fructose intake from 12% to 4% among the participants.
At day 10, visceral adipose tissue decreased from 123 cm3 to 110 cm3 (P < .001). Liver fat decreased from a median of 7.1% to 3.8% (P < .001) in all but one of the 38 participants, which remained significant after adjustment for weight change (P = .004). Compared with baseline, de novo lipogenesis was significantly lower for 37 participants (area under the curve = 29.7 vs. 68.4; P < .001).
Among nine participants who did not lose weight, liver fat decrease was still significant, decreasing from 9.7% to 6.3% at day 10 (P = .02). Similarly, visceral adipose tissue decreased from 124 cm3 to 91 cm3. De novo lipogenesis decreased from 59.9 to 30.1 (P = .006).
Additional findings included significant increases in insulin sensitivity and oral glucose tolerance test clearance rate and decreases in fasting insulin secretion rate and insulin secretion rate during the oral glucose tolerance test (all P < .001)
“We document improvements in liver fat, [de novo lipogenesis], insulin kinetics, and to a lesser extent [visceral adipose tissue], in obese children when sugar in the diet is replaced with starch; that is, a glucose-for-fructose exchange. Liver and visceral fat are thought to play a prominent role in metabolic dysfunction,” the researchers wrote. “This study provides evidence that support public health efforts to reduce sugar consumption as a means to improve metabolic health.” – by Talitha Bennett
Disclosure: Schwarz reports no relevant financial disclosures. Please see the full study for the other researchers’ relevant financial disclosures.