Intermittent fasting could improve nerve regeneration

Intermittent fasting is more than the latest diet fad, it has proven benefits –at least in animal models– against longevity, and it appears that it could even improve nerve regeneration, according to new research.

The problems with axons in the peripheral nervous system is that their regenerative capacity is not very high. There are certain external factors that can increase this capacity, like exercise or environmental enrichment, and according to this new study ¹, intermittent fasting might be another one.

3-Indolepropionic acid (IPA), a gut metabolite produced by the bacteria Clostridium sporogenesis, seems to be key in this process. IPA had been previously shown to promote axonal –nerve– regeneration, so the researchers decided to test whether intermittent fasting could have an effect on the gut microbiome that might affect IPA levels and, in turn, nerve regeneration.

To this end, mice got their longest nerve, the sciatic nerve, crushed and were split in two groups: one could eat as much as they wanted whenever they wanted, whereas the other could eat normally one day and fast the next. After 10 and 30 days, nerve growth was measured in both mice groups. In the intermittent fasting groups, the nerve had regrown about 50% more than in the group with normal feeding.

Moreover, the blood levels of IPA in the food-restricted group were higher than in the other group. And to clarify whether IPA was responsible for this increased regrowth, the researchers administered IPA directly to some mice after injury, and observed that these mice healed faster than those who didn’t receive any extra IPA.

This study demonstrates the potential of intermittent fasting to improve nerve regeneration, but exactly how much IPA is required to achieve these effects, whether direct administration would be more effective, and the optimal fasting parameters to achieve the greatest effects are still unknown. Further, whether the results translate to humans requires further research. However, it is a breakthrough study that paves the way for future non-invasive interventions to potentiate nerve regeneration and recovery.