It may be possible to live longer and increase fertility by manipulating diet, according to world-first research in mice from the University of Sydney’s Charles Perkins Centre.
Researchers showed for the first time in mammals that there is an ideal balance of macronutrients (protein, carbohydrates and fat) for reproduction and another, different ideal balance for increasing lifespan.
The research, published in the Proceedings of the National Academy of Sciences (PNAS), calls into question the long-standing theory that animals are forced to trade-off between reproduction and longevity when resources are limited. According to the researchers, it is possible to manage diet at different life stages to both optimise fertility and extend lifespan, rather than sacrificing either.
“This study takes a very big step in explaining why trade-offs between reproduction and longevity are not inevitable in mammals,” said Dr Samantha Solon-Biet from the Charles Perkins Centre, who co-led the research with Dr Kirsty Walters from the Charles Perkins Centre and ANZAC Research Institute.
“Rather than a trade-off, we now know that each evolutionary function has different nutrient requirements. That means that as our nutrient requirements change with our life stage, we can change our diet to suit our current requirements, for example by increasing our protein to carbohydrate ratio when in our reproductive prime and lifting our carbohydrate to protein ratio in later life.
“Animals don’t have to choose between high fertility and a long life. By managing diet throughout our life cycle, we can have both.”
The findings open the door for the development of dietary treatments for infertility in humans.