Fasting and Future Generations
There are various types of fasting that have gained popularity over the past few years. These include intermittent fasting, the 5:2 diet, time restricted eating and calorie restriction. The possible benefits of these diets is widely discussed.
However, the impact of these diets on future generations has not been given much consideration. Recent research from the University of East Anglia found that fasting diets could impact the health of future generations (1).
The research team investigated the effect of time-limited fasting on lifespan and reproduction in roundworms and three generations of their descendants.
Roundworms are obviously physiologically different from humans but they are often used for studying ageing and longevity because they share many genes with humans and the molecular pathways involved in the fasting response are evolutionarily conserved, which means the same pathways exist across a multitude of species, including humans.
Roundworms also have a short life cycle of just two weeks, so their development, and that of their offspring, can be assessed in a relatively short amount of time. Doing a similar study across humans could take a century.
The Intergenerational Study
They studied more than 2,500 worms across four generations. The first generation of worms were placed in one of four environments, including being able to eat as much as they liked, or being on a fasting diet. Four generations of offspring from these parents were then put on either full-feeding or fasting diets.
The team found that fasting did increase the lifespan of the roundworms. It also improved offspring performance in terms of reproduction, when offspring themselves were fasting.
However, fasting reduced offspring performance when the offspring had access to unlimited food. This effect continued down to their grand children and great grandchildren.
The research shows that fasting may be costly for descendants and this effect may last for generations. The researchers stress the importance of carefully considering the long-term effects of fasting to improve one’s own health and longevity as it may have detrimental effects on future generations.
See also the blog post on Food Labelling Explained for information on what to look out for when buying food, and the blog post on Tell Children Benefits of Food for information about how to help your children make healthy food choices.
1. Ivimey-Cook ER et al. Transgenerational fitness effects of lifespan extension by dietary restriction in Caenorhabditis elegans. Proceedings of the Royal Society B, 2021