Effects of Day-On-Day-Off Fasting on Telomere Length

Abstract

Aging has been studied in scientific literature for a long time. According to research, telomeres, the repetitive nucleotide sequence at the ends of chromosomes, naturally shorten with age, exposing the genetic material contained within the chromosome to damage and leading to impaired tissue regeneration. This damage leads to a variety of negative consequences, such as cellular and tissue dysfunction. Additionally, research indicates that shorter telomeres increase the risk for many of the diseases associated with aging, such as cancer, cardiovascular disease, Type 2 diabetes, and dementia. Given the link between fasting and these positive physiological changes, and the wide variation in fasting types and durations, research is needed to determine which fasting types and durations might increase TL. 

This study investigated a 68-year-old man using a crossover design in which he served as both the control and test subject over 140 days. During the 70-day control phase of the study, he ate his normal diet with no IF. During the 70-day test phase, he ate during a 12-hour period (a day on), followed by a 36-hour fast (a night, a day off, and another night). He repeated this two-day IF cycle 35 times. Blood was drawn and tested before the control phase, between the two phases, and following the test phase using the 6-Panel Flow Cytometry and Fluorescence in Situ Hybridization (Flow-FISH) TL test.

Prolonged fasting without other behavior interventions would lengthen telomeres, the results showed that during the test phase, the subject’s TL declined across all six blood-cell types tested. During the control phase, the subject’s telomeres lengthened in three of six blood-cell types tested, declined in two, and remained unchanged in one. Overall findings of this study suggest that a day-on-day-off IF over 70 days did not increase telomere length and resulted in a decline in TL.