The prophet Joel’s call to fasting and prayer resonates deeply with the Lenten tradition, but its wisdom is timeless. On one level, fasting is a spiritual discipline: humbling the soul, turning inward, and cultivating a posture of dependence on God. On another level, it has surprising echoes in physiological renewal.
Even though the authors warn that fasting is subject to clinical oversight, I recently heard of a study suggesting that a 72-hour fast can trigger a kind of “regenerative reset” in the body, in particular, prompting stem-cell–based regeneration of immune cells, as though parts of our adult physiology can revert to a more youthful state.
I know these words are highly technical, but they are crucial for the purposes we are using them here. The idea is not that we must fast for three full days to gain benefit, but that even more modest fasts (perhaps six hours or longer) may set some of those same biological rhythms in motion.
Thus, we do not need to wait for Lent to practice fasting. As we reflect on our motivations toward spiritual disciplines, let us pray for the grace to respect them, not as rigid rites, but as channels through which God shapes our souls and bodies for ongoing flourishing.
[Research paper by Chia-Wei Cheng et al., (2014), entitled “Prolonged Fasting Reduces IGF-1/PKA to Promote Hematopoietic-Stem-Cell-Based Regeneration and Reverse Immunosuppression” (published in Cell Stem Cell)]