A February 2020 study by the University of Sheffield said,
“Dietary restriction [defined as “a reduction of particular or total nutrient intake without causing malnutrition”] is an unusual paradox which has attracted a great deal of interest within the field of ageing. Our results have now pointed us towards a more refined explanation of why it occurs, and have the potential to wholly shift the focus of future research.”
"Our most surprising finding was that under certain circumstances, restricted diets can also be the origin of particular types of damage to the individual. This enhanced understanding of the penalties and benefits of certain types of diets, will expedite the quest to identify pharmaceutical interventions which mimic dietary restriction."
"The effects of diet on health are huge, but we understand little of the exact mechanisms. Our work has now uncovered a surprising property of dietary restriction, in that it makes flies ill-prepared for rich diets. This was contrary to our expectations and contrary to current evolutionary theory. In the biology of ageing field evolutionary biology has been highly influential in guiding interpretation of more mechanistic research. Our work thereby contributes to the broader understanding of dietary restriction and the efforts to translate its benefits to humans."