Intermittent fasting has become one of the most popular diets, with research linking it to several health benefits.
In a study on mice, a team from the Massachusetts Institute of Technology (MIT) in the US looked at how fasting can help intestinal stem cells regenerate.
These cells are the source of new intestinal cells and their regeneration can help the intestine.
“We think that fasting and refeeding represent two distinct states,” Shinya Imada, a postdoctoral researcher at MIT and one of the study’s lead authors, said in a statement.
When nutrients become available, these stem cells and progenitor cells activate programmes that enable them to build cellular mass and repopulate the intestinal lining,” he added.
Cancer risk However, there’s a caveat: if cancerous mutations occur during this regenerative phase, the mice are at a higher risk of developing early-stage intestinal tumours.
Intestinal stem cells help to renew the lining of the intestine, which is replaced entirely every five to ten days.
Researchers highlighted that the study was conducted in mice with specific cancer mutations and that the more intricate human context may yield different results.
Due to research indicating multiple health benefits, intermittent fasting has gained popularity as a diet strategy.
Researchers are still looking into how it affects metabolism, though.
A research team from the Massachusetts Institute of Technology (MIT) in the US examined how intestinal stem cells can regenerate in mice through fasting.
These cells are the source of newly formed intestinal cells, and the intestine can benefit from their regeneration.
Three mouse groups were observed: one group fasted for 24 hours, another group broke their fast for 24 hours before eating at will, and the third group was allowed to eat as usual for the duration of the experiment.
The results, which were published in the journal Nature, show that when mice resume eating after a period of fasting, a particular pathway that was previously identified as responsible for improved regeneration becomes active.
Lead author of the study and MIT postdoctoral researcher Shinya Imada stated in a statement, “We think that fasting and refeeding represent two distinct states.”.
The capacity of cells to use lipids and fatty acids as an energy source allows them to survive in the fasted state when nutrient availability is limited. The regeneration is primarily fueled by the postfast refeeding state after that. These progenitor cells and stem cells activate programs that allow them to replenish the intestinal lining and increase cellular mass when nutrients become available,” he continued.
Cancer risk.
There is a catch, though: the mice are more likely to develop early-stage intestinal tumors if cancerous mutations take place during this regeneration phase.
According to Omer Yilmaz, an associate professor of biology at MIT and the study’s senior author, “having more stem cell activity is good for regeneration, but having too much of a good thing over time can have less favourable consequences.”.
The lining of the intestine is completely replaced every five to ten days, and intestinal stem cells aid in this renewal process.
Compared to other intestinal cell types, they are more prone to develop precancerous changes because of their rapid division.
Additionally, mutations that emerged in mice that did not fast were found to be less likely than those that did to result in the formation of polyps during the refeeding period.
The more complex human setting may produce different results, the researchers noted, since the study was carried out in mice with particular cancer mutations.
Yilmaz stated, “It is interesting that being in either the state of fasting or refeeding when exposure to mutagen occurs can have a profound impact on the likelihood of developing a cancer in these well-defined mouse models, but we still have a lot to learn.”.
