Adding sugar to the diet equals not-so-sweet results in mouse study
Tuesday, August 20, 2013.
It's in everything from catsup to cornflakes. Americans have been stirring it into their coffee or gulping it down in oversized sodas for decades. We know it can cause cavities and lead to weight gain, but it can't be that bad . . . or can it?
In an article published on August 13, 2013 in the journal Nature Communications, researchers from the University of Utah reveal that a diet providing 25% of its calories from added sugar-- an amount equivalent in humans to three cans of soda per day--doubled the rate of death of female mice and impaired territoriality and reproduction in males.
University of Utah biology professor Wayne K. Potts and his associates fed mice a nutritious control diet or the same diet with 25% of its calories in the form of a mixture of half glucose and half fructose (which is similar to the composition of table sugar) for 26 weeks. Animals caged separately according to gender were given the diets prior to being housed together for 32 weeks in large pens that allowed them to more easily establish territories and compete for mates. Since mice often live in human habitations they "happen to be an excellent mammal to model human dietary issues because they've been living on the same diet as we have ever since the agricultural revolution 10,000 years ago," Dr Potts noted.
The researchers observed that females given the higher sugar diet died at a rate that was twice that of the control animals and had a lower reproductive rate by the end of the study. Male mice on the sugary diet controlled 26% less territories and produced 25% fewer offspring. The adverse effects observed in the animals given the sugar-enhanced diet were of the magnitude as that which occurs among the offspring of inbreeding.
The National Research Council recommends that no more than 25 percent of calories in the human diet should be from added sugar. "They don't count what's naturally in an apple, banana, potato or other nonprocessed food," Dr Potts explained. "The dose we selected is consumed by 13 percent to 25 percent of Americans."
"These findings represent the lowest level of sugar consumption shown to adversely affect mammalian health," the authors write. "Clinical defects of fructose/glucose-fed mice were decreased glucose clearance and increased fasting cholesterol."
"This demonstrates the adverse effects of added sugars at human-relevant levels," Dr Potts stated. "I have reduced refined sugar intake and encouraged my family to do the same."