"Our results provide evidence that added sugar consumed at concentrations currently considered safe exerts dramatic adverse impacts on mammalian health," researchers said. (Agencies)
"This demonstrates the adverse effects of added sugars at human-relevant levels," said Wayne Potts, the study's senior author.
Potts said that the new test showed that the 25 percent "added-sugar" diet - 12.5 percent dextrose (the industrial name for glucose) and 12.5 percent fructose - was just as harmful to the health of mice as being the inbred offspring of first cousins.
Even though the mice didn't become obese and showed few metabolic symptoms, the sensitive test showed "they died more often and tended to have fewer babies," said the study's first author, James Ruff.
"We have shown that levels of sugar that people typically consume - and that are considered safe by regulatory agencies - impair the health of mice," said Ruff.
The new toxicity test placed groups of mice in room-sized pens nicknamed "mouse barns" with multiple nest boxes - a much more realistic environment than small cages, allowing the mice to compete more naturally for mates and desirable territories, and thereby revealing subtle toxic effects on their performance, Potts said.
"This is a sensitive test for health and vigour declines. The mice tell us the level of health degradation is almost identical from added-sugar and from cousin-level inbreeding," said Potts.
The study says the need for a sensitive toxicity test exists not only for components of our diet, but "is particularly strong for both pharmaceutical science, where 73 percent of drugs that pass preclinical trials fail due to safety concerns, and for toxicology, where shockingly few compounds receive critical or long-term toxicity testing."
The experimental diet provided 25 percent of calories from added sugar - half fructose and half glucose - no matter how many calories the mice ate. Both high-fructose corn syrup and table sugar (sucrose) are half fructose and half glucose.
The diet fed to the mice with the 25 percent sugar-added diet is equivalent to the diet of a person who drinks three cans daily of sweetened soda pop "plus a perfectly healthy, no-sugar-added diet," Potts said.
"Our results provide evidence that added sugar consumed at concentrations currently considered safe exerts dramatic adverse impacts on mammalian health," researchers said.