Zurich. Until now, the main focus has been on consuming large amounts of sugar. Researchers at the University of Zurich are now reporting that even moderate amounts of fructose and table sugar in lemon juice doubled the body’s production of fat in the liver, as a study of 94 young adults showed. They consumed drinks sweetened with different types of sugar every day for seven weeks, while the control group did not.
The drinks contained fruit sugar (fructose), dextrose (glucose) or table sugar (sucrose, which is made up of fructose and glucose). The researchers used “tracer” to analyze the beverage’s effect on fat metabolism (J Hepatol 2021; March 5 online).
Table sugar had a particularly negative effect
Overall, participants consumed no more calories than they had before the study. Due to a certain satiety of the sweet drink, they even reduced the amount of other calories. However, fructose had a negative effect: “The body’s production of fat in the liver was twice as high in the fructose group as it was in the glucose or control group – and this is more than twelve hours after the last meal or last sugar consumption,” study lead Philip Gerber said of The Clinic for Endocrinology, Diabetes and Clinical Nutrition is in contact from the university.
Surprisingly, the most consumed table sugar boosted lipid synthesis more than the same amount of fructose. Because until now, fructose in particular has been suspected to cause such changes. “At least 80 grams of sugar a day – about 0.8 liters of soft drink – stimulates fat production in the liver. Hyperactivity continues for a long time, even if no more sugar is consumed,” Gerber says.
Increasing fat production in the liver is an important first step in the development of common diseases such as fatty liver or type 2 diabetes. The World Health Organization recommends limiting daily sugar consumption to 50 grams or even 25 grams. (eb / eis)