The study involving putting wild mice on a healthy diet plus a sugar mix meant to represent three sodas worth a day for humans. The scientists then unleashed the mice in a natural environment, where they had to compete against regular wild mice that hadn't been raised on the sugar water.

They found that the female mice who were loaded with sugar also had shorter lifespans, while their male counterparts had produced less offspring.  Wayne Potts, a biologist at the University of Utah and the study's lead scientist, interprets his findings as a warning.
"If it makes a mouse sick, then do you want it in your body? At least before we work out the mechanistic basis of that sickness and are able to evaluate whether it's also going on in humans or if it's an mouse-specific phenomenon."
The study is the first to examine the effects of added sugar intake in lab animals at levels that are equivalent to what some humans normally consume. 

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