High glycemic index diet raises hepatic fat, glycogen stores

(HealthDay)—A one-week high glycemic index (HGI) diet increases hepatic fat and glycogen stores in healthy adults compared with a low glycemic index (LGI) diet, according to a study published online Sept. 4 in Diabetes, Obesity and Metabolism.

Stephen Bawden, Ph.D., from the University of Nottingham in the United Kingdom, and colleagues examined the acute and long-term effects of LGI and HGI diets in healthy volunteers. Eight healthy males underwent testing before and after a seven-day macronutrient and energy matched HGI or LGI diet, followed by a minimum four-week washout period, and repetition of the intervention with the alternative diet.

The researchers found that following the HGI versus LGI test meal, there were significantly greater plasma glucose and insulin peak values and area under the curve. Following the HGI test meal, there was a greater increase in hepatic glycogen concentrations (P < 0.05); compared with the beginning of the intervention, peak levels were significantly greater after seven days of HGI dietary intervention (P < 0.05). There was a significant increase in liver fat fractions after the HGI versus LGI intervention.

"Compared to an LGI diet, a one-week HGI diet increased hepatic fat and glycogen stores," the authors write. "This may have important clinical relevance for dietary interventions in the prevention and management of non-alcoholic fatty liver disease."

Several authors disclosed financial ties to Unilever.