A March 2020 study by the MRC London Institute of Medical Sciences and Kiel University said,
"Just like humans, flies fed a high-sugar diet show many hallmarks of metabolic disease - for instance, they become fat and insulin resistant."
"Obesity and diabetes are known to increase mortality in humans, and so people always assumed that this was how excess sugar is damaging for survival in flies".
"Water is vital for our health, yet its importance is often overlooked in metabolic studies. Therefore, we were surprised that flies fed a high-sugar diet did not show a reduced lifespan, simply by providing them with an extra source of water to drink. Unexpectedly, we found that these flies still exhibited the typical metabolic defects associated with high dietary sugar".
The researchers found that the excess sugar is related to a build up of uric acid but that,
"the sugar-fed flies may live longer when we give them access to water, but they are still unhealthy. And in humans, for instance, obesity increases the risk of heart disease. But our study suggests that disruption of the purine pathway is the limiting factor for survival in high-sugar-fed flies. This means that early death by sugar is not necessarily a direct consequence of obesity itself".
"Strikingly, just like flies, we found that dietary sugar intake in humans was associated with worse kidney function and higher purine levels in the blood."
"It will be very interesting to explore how our results from the fly translate to humans, and whether the purine pathway also contributes to regulating human survival."
"There is substantial evidence that what we eat influences our life expectancy and our risk for age-related diseases. By focusing on the purine pathway, our group hopes to find new therapeutic targets and strategies that promote healthy ageing".