Intermittent fasting and calorie restriction are two dietary strategies that have been shown to prevent age-related illness and increase longevity. Despite their popularity, it’s still unclear how anti-aging diets might have such dramatic health benefits.
A team of scientists lead by Mitchell Lee set out to research anti-aging dietary strategies in a new AAAS study. Beyond distinguishing fact from fiction, the researchers wanted to see if the therapies used the same mechanism to prolong life.
Dietary interventions appear to postpone or reverse the molecular pathways of aging in model species such as mice, flies, and yeast. It is now impossible to tell whether such diets effect biological aging in people, according to the study’s authors.
The researchers noted, “We investigated some of the most prominent antiaging diets, including calorie restriction, intermittent fasting, fasting-mimicking diets, ketogenic diets, time-restricted feeding, protein restriction, and essential amino acid restriction.”
“We learned a lot about these nutritional therapies by comparing them to traditional calorie restriction (CR).” Many studies fail to account for the diet group’s lower calorie consumption, making it impossible to separate their effects from CR.”
“Although commonly portrayed as universally advantageous, the effects of CR on life span are extremely dependent on genotype and, in certain situations, result in decreased survival.” These investigations have substantially enhanced our understanding of the cellular response to decreased nutrition availability, despite their limitations.”
“A picture of a complex network comprising of various signaling pathways that converge on important molecular hubs is beginning to emerge; chief among these is the mechanistic target of rapamycin (mTOR).”
Because mTOR and its components are well-studied therapeutic targets, the researchers added, there is still a lot of interest in pharmacologically targeting this network to extend life and improve health.
“Human studies, both correlative and controlled, are consistent with health benefits conferred by a CR diet. However, it remains unresolved whether these benefits are a consequence of modulating the aging process itself or are simply the result of avoiding obesity,” explained the researchers.
Future study should focus on a deeper understanding of the cellular and molecular mediators of anti-aging diets, according to the researchers.
The research was published in the scientific journal Science.