SINGAPORE: Drinking beverages with high fructose content first thing in the morning can overwhelm the digestive system and may disrupt beneficial gut bacteria, according to a study by Princeton University that was published on Tuesday (Feb 6).
In mice tests, a mixture of equal parts of fructose and glucose was fed to mice. Researchers then traced how the sugars were digested in the rodents’ digestive tracts.
After a period of fasting, such as sleep, the researchers found that the stomach is unable to process large amounts of fructose, which is present in drinks such as orange juice and soda.
When this happens, the fructose spills over into the large intestine. This is where the sugar comes into contact with the colon’s microbiome.
"The microbiome is designed to never see sugar," said Professor Joshua Rabinowitz of the Lewis-Sigler Institute for Integrative Genomics at Princeton University.
"One can eat an infinite amount of carbohydrates, and there will be nary a molecule of glucose that enters the microbiome. But as soon as you drink the soda or juice, the microbiome is seeing an extremely powerful nutrient that it was designed to never see,” said
While the study did not show how fructose influences the microbiome, the researchers found that fructose is better digested by the small intestine after the mice have been fed. The findings, published in the journal Cell Metabolism, showed that more than 90 per cent of fructose is digested in the small intestine.
“We saw that feeding mice prior to sugar exposure enhanced the small intestine's ability to process fructose and that protected the microbiome from sugar exposure,” said Prof Rabinowitz.