Fasting as Healthspan Maintenance, Relevance for Tissue Rejuvenation, Cancer & More | Rhonda Patrick

And that is a little bit more of a prolonged fast. There's a lot of work by Dr. Valter Longo, who is a friend of mine. And as this gentleman over here mentioned, I do have a podcast where I interview a variety of scientists, physicians, and we talk about a lot of topics that are related to aging. And so I've spoke with him multiple times, and he has a variety of clinical studies where he has looked at the effects of basically not eating food for a prolonged period of time, which is around 48, at least 48 hours. And he's looked at the effects of that on, for example, autoimmune-related diseases. So people that had multiple sclerosis, they were doing— in that case, it wasn't actually a fast, they were doing a fasting-mimicking diet.

So it was a diet that was sort of— had a very specific caloric content and macronutrient composition that activated a lot of the same molecular pathways that fasting does, and it improved a variety— it improved disease status in the multiple sclerosis patients. He's also been a co-author on studies where he's shown that there may be a benefit to fasting along with standard of care treatment when you're undergoing cancer treatment like chemotherapy or radiation. So he's published a couple of pilot studies showing that A 48-hour water fast is safe. And not only is it safe, there seems to be a beneficial effect on sensitizing cancer cells to death and protecting normal cells from the toxicity of chemotherapy and/or radiation.

And that largely has to do with the fact that fasting activates those stress response pathways I just mentioned. that are meant to be switched on that humans, because of our 24-hour access to food these days, never switch on. Well, normal cells switch them on, and so when you switch on those stress response pathways, they actually become more resilient to stress like chemotherapy, radiation. Those are very toxic types of stress. Normal cells become more resilient to them because they have increased activation of genes that are involved in dealing with oxidative stress, in dealing with inflammatory stress, in dealing with the kind of stuff that's causing them to die from this chemotherapy or radiation. Cancer cells are unable to do that.

They're completely screwed up, mutations, all sorts of mutations. When they experience a stressful— when something is stressing them out, they don't respond by increasing stress response pathways. They just die. So that's another area that I think is really interesting in terms of healthy people doing it to prolong their lifespan. It's an open question. Valter thinks that in people that are lean and don't have any cardiovascular risk factors or any other type 2 diabetes risk factors, that they can maybe do this once or twice a year, and they may help improve longevity. That's speculation at this point. It hasn't been shown in humans, but there have been animal studies showing that it does increase lifespan and increases healthspan.

Valter's shown that doing a prolonged fast can basically cause organs to shrink inside of animals during the fasting phase, and that is due to a variety of factors. One, cell size is shrinking. Two, cells are dying. And what Valter has shown is that preferentially damaged old cells die. And this then can— Yeah. Basically, during the refeeding phase, which I think now that was a question I missed, when you're breaking your fast, the refeeding phase causes stem cells to proliferate and to replace all those cells that were lost. And so the organs that shrunk regrow, and they're regrowing with healthy new young cells. So it's really this amazing rejuvenation process that seems to be hard encoded in our genes. and activated just by not eating. So a lot of work to still be done there.

Huge implications for autoimmune disease. I mean, what Valter has shown in a lot of animal studies is that immune cells that are dysfunctional, those are preferentially killed off and replaced by healthy new non-autoimmune cells, which is amazing. So I think there's a lot of promise for prolonged fasting, and not only the treatment for maybe cancer and autoimmune diseases and other diseases, but also even possibly to improve healthspan in healthy people. And so I really look forward to that research progressing. I think it's a really hot new area that I'm very excited about. And I think my red dot is totally like going berserk here, so I'm supposed to stop.