- U.S. researchers gave mice sugary diet and found female animals died twice as fast as those eating healthy snacks
- Scientists from the University of Utah found male mice consuming the sugary diet were less able to hold territory and reproduce
- Strangely the animals showed no signs of ill-health including obesity or raised blood sugar levels
Scientists said 'safe' levels of dietary sugar - found in a can of fizzy drink, for example - could be having invisible adverse effects on people's health
Even 'safe' levels of sugar could be having invisible adverse effects on our health, American researchers.
Researchers gave mice the equivalent of a healthy human diet plus three cans of fizzy drink a day and found the female animals died twice as fast as those whose food was not largely composed of sugar.
Male mice consuming the sugary diet were less able to hold territory and reproduce, leading scientists to speculate that sugar has a damaging effect on the health of mammals, including humans.
Scientists from the University of Utah said the mice showed no sign of suffering serious physical changes in their bodies.
Writing in the online edition of the journal Nature Communications, the researchers said: 'Our results provide evidence that added sugar consumed at concentrations currently considered safe exerts dramatic adverse impacts on mammalian health.'
Mice on the experimental diet received 25 percent of their energy intake in the form of added sugar, no matter how many calories they ate.
In human terms this was equivalent to a person eating a normal healthy diet plus three cans of sugar-sweetened fizzy drinks a day.
After 32 weeks, more than a third of the female mice fed extra sugar died - twice the number fed a non-sugary diet.
The death rate of males was not affected, but their survival behaviour was.
Males on the sugary diet acquired and held on to 26 percent fewer territories than their normal diet nest-mates and produced 25 percent fewer offspring.
Researchers gave mice the equivalent of a healthy human diet plus three fizzy drink cans a day and found the female animals died twice as fast as those whose food was not largely composed of sugar. Male mice consuming the sugary diet were less able to hold territory and reproduce
Study leader Professor Wayne Potts,at the university, said: 'This demonstrates the adverse effects of added sugars at human-relevant levels.'
To observe the mice in a more realistic setting, the researchers kept them in room-sized pens rather than cages.
This allowed them to compete more naturally for mates and desirable territories.
Despite the effects on the mice, the sugar-fed animals showed only minor metabolic changes, including raised cholesterol.
The study found nothing unusual in terms of obesity or insulin and blood sugar levels.
'Our test shows an adverse outcome from the added-sugar diet that couldn't be detected by conventional tests,' said Professor Potts.
The study found nothing unusual in terms of obesity or insulin and blood sugar levels. Professor Potts believes the test shows an adverse outcome from the added-sugar diet that couldn't be detected by conventional tests
