6. Fasting in cancer treatment and cancer prevention

March 18, 2023 with Dawn Lemanne, MD & Deborah Gordon, MD
6. Fasting in cancer treatment and cancer prevention
Show Notes Transcript Chapter Markers

In this episode, Drs. Lemanne and Gordon discuss research on the role of fasting in the treatment and prevention of cancer.  Dr. Lemanne discusses her personal experience of fasting, and how she uses fasting in the cancer clinic.

  • Exactly when to fast for best cancer outcome
  • Combining fasting and chemotherapy improves survival--animal studies
  • Types of fasts, including water fasts and dry fasts
  • Research on dry fasting and kidney function (prepare to be surprised)
  • Eating dinner late increases cancer risk
  • Daily intermittent fasting, minimum effective length
  • Extended fasts

Meth EMS, van Egmond LT, Moulin TC, Cedernaes J, Rosqvist F, Benedict C. Association of Daily Eating Duration and Day-To-Day Variability in the Timing of Eating With Fatal Cancer Risk in Older Men. Front Nutr. 2022 May 10;9:889926. doi: 10.3389/fnut.2022.889926. PMID: 35619965; PMCID: PMC9127957.

Links and references of interest:

Study evaluating the effect of late dinner on breast and prostate cancer risk 

Chemotherapy and timing of fasting, University of Southern California study

Chemotherapy patients who fast report fewer side effects. Longo group, 2009

UCSF fasting page has been taken down. Here is one from City of Hope Cancer Center, in southern California/ greater Los Angeles area

Fasting cycles retard growth of tumors and sensitize a range of cancer cell types to chemotherapy. Sci Transl Med. Longo group, 2012 PMID: 22323820

Dawn Lemanne, MD
Oregon Integrative Oncology
Leave no stone unturned.

Deborah Gordon, MD
Northwest Wellness and Memory Center
Building Healthy Brains

[00:00:00.090] - Dr. Lemanne

There's a case study from the Fasting clinic in Santa Rosa. They published the original case and then a follow up a few years later of a patient. I believe it was a woman, maybe early middle age, who had a follicular non Hodgkin lymphoma. And these are tumors that are known to wax and wane for reasons unknown to human beings. But anyway, this patient went to this clinic, and I believe she fasted for something like 14 to 21 days on water. And her lymphoma regressed and quieted. And I don't recall if she's free of any signs of this lymphoma. But when they published a follow up a few years later, she was still doing very, very well. 


You have found your way to the Lemanne Gordon podcast, where Docs Talk Shop. Happy eavesdropping! 


I'm Dr. Dawn Lemanne. I treat cancer patients.


[00:00:56.750] - Dr. Gordon

I'm Dr. Deborah Gordon. I work with aging patients.


[00:01:00.540] - Dr. Lemanne

We've been in practice a long time.


[00:01:02.930] - Dr. Gordon

A very long time.


[00:01:04.600] - Dr. Lemanne

We learn so much talking to each other.


[00:01:06.780] - Dr. Gordon

We do. What if we'd let people listen in? 


In this episode, Dr. Lemanne explores fasting, some of the strategies, patterns, and benefits she's seen in her own life and with her patients. One of the most surprising things was her take on dry fasting refraining not only from food, but also from water. Let's listen. 


One of the first things I learned from you that was really beneficial, and it's something I've carried with me as an action item with my patients is the observation that you shared with me studies, I believe that women who have some degree of metabolic syndrome and are diagnosed and treated for breast cancer have less recurrence if they adjust their diet. I believe it was a prolonged overnight fast. It was something that reduced their metabolic dysfunction, their belly fat, and their insulin resistance. This question has come up again for me recently with some other patients with cancers. So I just want an update from you on what would be all the ways that you as an oncologist or myself as a physician with patients who are seeing the oncologist, how does fasting fit in now in your worldview of approaching cancer prevention and treatment?


[00:02:39.580] - Dr. Lemanne

Fasting is the bomb. Fasting is a fantastic tool for a lot of people to improve their metabolic health, decrease their risk of getting cancer, improve their chances of surviving if they do get cancer, improve the treatment efficacy, and decrease side effects for certain types of treatment, like certain chemotherapy drugs. So fasting is a practice that most people can benefit from whether they have cancer or not, and whether they're worried about cancer.


[00:03:06.830] - Dr. Gordon

Everybody is worried about cancer.


[00:03:08.630] - Dr. Lemanne

I think you're right. And just to broaden the perspective, it's not just about cancer. It's about general health. And other diseases are affected by fasting practices and one's metabolic health.


[00:03:19.660] - Dr. Gordon

In general, would you say that it reduces risk of any kind of cancer from basal cell to colon cancer?


[00:03:25.660] - Dr. Lemanne

That's a great question. Some cancers are not so related to nutritional or metabolic problems. Some cancers are directly related to infection. For instance, in Africa, Epstein Barr virus and malaria combine to create a cancer called Burkitt's lymphoma in children. Now, these children don't necessarily have diabetes type two or overweight or anything like that, but the combination of those two pathogens sets them up for development of this particular very deadly malignancy. And changing their diet won't help. They need to be treated for the malignancy itself. Most people are concerned about in the United States these days are the common cancers of older adulthood. So we're talking about breast cancer, colon cancer, certain types of lung cancer, especially in nonsmokers, pancreatic cancer, possibly kidney cancer, myeloma, endometrial cancer. The list is longer than that. But those are some of the cancers that we know are associated with overnutrition, meaning too many calories over a long period of time that can be somewhat addressed with changes in that overnutrition.


[00:04:27.170] - Dr. Gordon

And prostate cancer would be in that list as well would prostate cancer is.


[00:04:31.020] - Dr. Lemanne

Probably in that list for most people, although there certainly are different flavors of prostate cancer as well. We're still sorting that out. And prostate cancer may behave differently depending on which stage you're at. One of the things that I want to talk about is what is fasting? Yes, when I talk about fasting with my patients, I mean no calories. And there are different definitions of fasting. Some people say, well, I want to do a fat fast and they'll eat calories from lipids, fats only. That's not what I'm talking about. 


I am talking about using water and a caloric, non caloric liquids to maintain hydration. And sometimes I will ask my patients to use various salts, sodium, magnesium, potassium to keep things in balance during a prolonged fast. I want to make it clear what we're talking about when I'm talking about fasting. I'm talking about no calories.


[00:05:19.590] - Dr. Gordon

No calories, but allowing liquids to…non caloric liquids ad libidum as the patients…


[00:05:28.810] - Dr. Lemanne

Some patients are addicted to coffee. I would be in that class. They can have tea, coffee, other types of herbal teas that have no calories would be allowed, and basically water and sometimes some salt in that water.


[00:05:42.450] - Dr. Gordon

So speaking to the people who are not yet your patients who don't ever want to be your cancer patients, what kind of non-caloric, liquid fasting routine are we talking about? A day at a time, three days at a time? A month, a year?


[00:06:00.130] - Dr. Lemanne

That's a great question. We don't know the answer to that. But we have some hints about what different types and lengths of fasts might do. So people have heard of intermittent fasting, which these days means restricting food to a certain period of time during the day and abstaining from calories, usually during an overnight period, a prolonged 13 hours or more. There are also fasts of 24 hours or 36 hours or 72 hours as long as you want to go. And they all do slightly different things. The longer you fast, the more you turn on new and differing ways of dealing with caloric absence. And all of them are beneficial for your body. So there's kind of a cascading effect and a short overnight fast of say, 13 hours, which is where we start to see the benefit. So less than 13 hours, you're not really going to see much metabolic benefit.


[00:06:49.290] - Dr. Gordon

I think people sleep better if they're not eating right up to bedtime. But you're saying in terms of shifting their metabolism, there's not a particular benefit with just fasting for eleven or 12 hours.


[00:07:00.310] - Dr. Lemanne

Right. The benefits start to accrue at 13 hours. That's where we can really start to measure them. So there was an interesting study that was published in the Journal of the American Medical Association about five years ago, and it was an observational study of women who'd been diagnosed with breast cancer. And those who fasted 13 hours or more had a lower risk of recurrence over the three or so years of observation, than did those who fasted for 12 hours or less. So that dividing line was right at 12 hours.


[00:07:27.680] - Dr. Gordon

Huge difference. That's the study that you first told me about several years ago, and I just told people, stretch it to 13, just stretch it to 13. That was a risk of recurrence. But would you say that same principle probably applies to prevention as well?


[00:07:41.750] - Dr. Lemanne

I would. And one of the things, that I have bad news for all of us, and that's that food, any food, even the most beautiful organic keto, green, anything, is carcinogenic.


[00:07:54.070] - Dr. Gordon

So just stop eating.


[00:07:56.150] - Dr. Lemanne

Once in a while we should stop eating. So the metabolism of food creates free radicals and reactive oxygen species, things that are toxic to our DNA and damage our DNA. Every time you damage your DNA and repair it, there's a chance of developing a cancer. The chance is really low, but there it is. So the more you eat, the higher your chances. And by the time we all get to 100, our chances are pretty much almost 100% as well. So taking breaks from eating is the mechanism we think causes prolonged life expectancy in animals. So laboratory studies show that the less you feed an animal and or the more you make it fast for longer periods, say more than 24 hours, the longer it's going to live. That's been known for almost 100 years. The studies are so consistent in laboratory animals all the way from Earthworms, drosophila, which are fruit flies, even yeast, and up through vertebrates and mammals. So that's something that's very, very well known in the scientific world, and I think we can learn a lot from that. It's not been tested in humans and never will be formally, I don't suppose, because how would you do that ethically?


[00:09:05.400] - Dr. Lemanne

But yes, fasting will have cancer preventive effects for most people if you are worried about cancer and you're fully grown. So this is not for children, but people whose height and adult weight have been attained, periodic fasting, at least 13 hours overnight and perhaps a longer fast of 24 hours once or twice a month, and perhaps an even longer fast of up to three days, two or three days, 48 to 72 hours, once or twice a year would probably be beneficial.


[00:09:38.130] - Dr. Gordon

We're talking about in cancer prevention, you're saying at its longest, kind of a pretty safe and reasonable thing to suggest to a lot of people. You could do it for up to three days. And I've heard the first day is the worst, and after that tends to get a little easier for people.


[00:09:50.800] - Dr. Lemanne

So, yes, the first day is the worst. People tend to have a lot of fluid shifts that first day. When you don't eat, your body tends to remove sodium. So for people who have high blood pressure, their blood pressure will often completely normalize after 24 to 48 hours without food. If you're on blood pressure medication, you may want to stop them before you.


[00:10:11.170] - Dr. Gordon

Start your fast or at least check your blood pressure.


[00:10:13.800] - Dr. Lemanne

At least check your blood pressure. And if it goes down too low, don't take your next dose if you're fasting. Of course, nobody would do any type of fast if they're on medications for blood pressure without checking with their physician or with a physician who is versed in the science and art of fasting. So I think a lot of physicians are very afraid of fasting and will just have kind of a knee-jerk reaction, oh, don't do that. That's just a terrible idea. Well, it's not a terrible idea. The animal studies over 100 years are very consistent that it's a healthy practice, that you can't be healthy unless you partake of, in other words, most people will be healthier if they add fasting to their health routines.


[00:10:53.830] - Dr. Gordon

It's certainly been a part and some of the big fasting proponents that we know through recent science and social media and things like that. Fasting has been a part of religious traditions.


[00:11:07.620] - Dr. Lemanne

A traditional fast I think in all those traditions, it's 40 days and 40 nights. I think that was Buddha, I think that was Moses, and that was Jesus, you know, so 40 days and 40 nights. I don't know anybody who's fasted in the biblical sense, which is no food and no water for 40 days and 40 nights. But there are people who have been experimenting with something called dry fasting, which is no food and no water. This is not something I would recommend that anyone undertake unless they're under the supervision of a physician. And even then, one could question whether that's a wise thing to do. But I'll tell you a secret. I've been experimenting with dry fasting myself. Yes. And I'll tell you that I’ve found it to be much, much easier than water fast.


[00:11:51.910] - Dr. Gordon



[00:11:52.730] - Dr. Lemanne

Yes. So the first 24 hours are much easier, and I think it's because of the fluid shifts. When you don't take in water as well as food, your blood becomes a little bit more concentrated and the sodium level stays the same. When you take in water, you waste sodium, the sodium level goes down and you feel horrible.


[00:12:08.590] - Dr. Gordon

In marathon athletic events, there have actually been deaths from replacing fluid loss by sweating with just plain water.


[00:12:19.150] - Dr. Lemanne

Right. Some of the marathoners have taken in huge amounts of just plain water and die.


[00:12:23.930] - Dr. Gordon

And died. Your first day of a dry fast, you're saying, is actually easier than your first day of a water only?


[00:12:32.020] - Dr. Lemanne

Yes, I prefer it. I've only done 24 hours dry fasting. That's the maximum I've done. But I've found it easier. I've found it actually delightful. One of the things that I've noticed with a dry fast is a great improvement in my brain function. I've found dry fasting to be a lot easier than water fasting. One of the symptoms that I have within the first 24 hours of water fasting is light headedness. Now, I can mitigate that with some salt intake. I use something called Good Salt, which is a brand of electrolyte replacement. It comes as a white crystalline powder, looks just like salt, tastes like salt. It's got sodium, potassium and magnesium in it, and I'll take a teaspoon of that or two a day, and that keeps the light headedness away. But with the dry fasting, I don't have that. My brain function after a dry fast is so much better. And one of the main things that I notice is an up-tick, in dreaming, I'll have much more vivid dreams. I'll recall them. Seems like the dreams go on and on throughout the night. So that's something I've noticed. I've noticed that with rapamycin as well.


[00:13:33.800] - Dr. Gordon

I could go in ten different branches from everything you've said so far. But one of the things I was going to say is I'm a self-confessed fasting wimp. I'm very good at fasting overnight from anywhere from twelve, which doesn't count, but from 13 to 16 hours, depending on if I'm exercising or something that day. And the idea of totally not eating for 24, 48, 72 hours, how much am I evoking the same benefit by taking rapamycin or fisetin?


[00:14:06.020] - Dr. Lemanne

Yes. I mean, those are great questions and we're going to find out, I think, with the research that's going on. It would be wonderful if we can take a pill and keep eating and get the same benefits. That would be fantastic.


[00:14:16.970] - Dr. Gordon

So on a personal level, you're telling me all these different activities of your brain, that it's sharper and that you dream more. Do you notice anything else on a physical level?


[00:14:26.800] - Dr. Lemanne

No, not really. It takes a day or two to recover. You have to replace your glycogen. Unless you go straight into a ketogenic diet. I'm not on a ketogenic diet these days because I like to work out hard. But I do find that over time, my health seems to be better if I do this every now and then, by every now and then in the last year, I've probably done a 24 hours dry fast. Maybe two or three times. Over the last four or five years, I've done many, many water fasts. Usually they're 24, 48, 72 hours. I did one seven-day water fast that was much easier than I ever dreamed it would be.


[00:15:04.400] - Dr. Gordon

Do you remember I ran into you at the food store in the freezer aisle? On your 7th day and you said, oh, I've been fasting, it's great. I said, oh, fasting, how hard for you? Why did you come to the store? And you know what you said to me? You said, Actually, I never want to eat again.


[00:15:20.550] - Dr. Lemanne

It's true that the hunger disappears after a few days it can come in waves, but their waves last about 40 minutes and then they dissipate and I'm not thinking about food, interested in food, I'm going about my business. I was active during that time. Exercising? No, I wasn't exercising formally, but I was active, I was up and about and I remember this was probably not too wise, but I took some kind of really smelly fumy paint and painted the porch because I had so much energy.


[00:15:53.010] - Dr. Gordon

Let me give you my address. And so when we think about it as cancer preventative, I'm sort of imagining that one of the benefits of this is an enhanced cleaning up of dead and damaged cells.


[00:16:08.590] - Dr. Lemanne

Yes. So there's likely a clearing out of senescent cells. One study looked at a small number of people who were undergoing a several day dry fast, no water at all, and their kidney function improved, which is kind of anathema, we think. Well, if you don't drink, water your kidney function is going to only get worse but their kidney function improved several other things improved. In animals cardiac function, lung function, liver, brain everything improves with fasting acutely. It improves mainly during the rebuilding phase so oh, and the immune system rejuvenates. So Valter Longo has done some really interesting work showing that after a five day fast or a fast mimicking diet, which he likes a lot. Animals and people, when they start eating again, there's a nice bloom of the immune system. The stem cells are reactivated. All of the immune cells are refreshed and replenished with spanking new ones. And the animals and people seem to have a really nice, improved immune system.


[00:17:06.570] - Dr. Gordon

Do we know on a cellular metabolism kind of level, is this a little bit like taking metformin or something like that to fast and starve your cells a little bit so they do house cleaning within the cells?.


[00:17:21.250] - Dr. Lemanne

So I think what you're getting at is the idea of autophagy and mitophagy. Autophagy is eating yourself, literally and mitophagy is the process that mitochondria go through when they dissolve and reconstitute themselves. And yes, I think there are lots of studies that suggest that that's one of the main mechanisms. Are there other ways to get that job done? The autophagy? Exercise to a certain extent can do it. Although I don't think the autophagy that you get that a normal person like me going to the gym a few times a week gets from exercise is going to match something that, say, an ultramarathoner is going to get running 100 miles or something like that. So that wouldn't be a realistic way for me to try to accomplish much autophagy. So fasting would be better for me. And then, of course, if we can get some pills that get the job done, that would be what everybody's hoping for.


[00:18:08.800] - Dr. Gordon

But the bottom line takeaway is that for cancer prevention, the studies will never be done on a sufficiently robust number size to adequately confirm this. But it's probably in our best interest for not only the health of our brains, but the health of our bodies and the option of preventing cancer to do a 24-hour, a 72-hour fast at some not too frequent cycle throughout your year, your lifetime.


[00:18:41.370] - Dr. Lemanne

I would say if people are looking for guidance, of course they would want to discuss this with their physician. What I will often tell my patients, if they're in pretty good health, there's nothing seriously going on, maybe they have some high blood pressure issues and we will then manage their blood pressure prescription during the fast. But a  24-hour fast, once or twice a month is a good thing to aim for. Of course, the 13 hours overnight fast, I think everyone should do that pretty.


[00:19:06.270] - Dr. Gordon

Much every day, right?


[00:19:07.390] - Dr. Lemanne

Every day, yes. And one of the worst things you can do for your health is to eat a late dinner. So there's a differential between people who eat dinner at eight and people who finish their dinner by 06:00 p.m. In terms of cancer risk, and then people who eat at night and eat up until bedtime, or wake up in the night and wake up in the night to eat or even just eat at 09:00 p.m. Right before they go to bed. There's a differential in cancer risk. We can measure that. Eating at night and eating your dinner late is probably not a great idea. But back to this suggested fasting schedule. So I will suggest that once or twice a month at 24 hours fast, maybe a couple of times a year, a longer fast, 48 hours, 72 hours, and every now and then if there's some issue going on, maybe every few years, a seven day fast or a five to seven day fast, a longer fast. There's a case study from the Fasting clinic in Santa Rosa. They published the original case and then a follow up a few years later of a patient, I believe it was a woman, maybe early middle age, who had a follicular non-Hodgkin lymphoma.


[00:20:08.870] - Dr. Lemanne

And these are tumors that are known to wax and wane for reasons unknown to human beings. But anyway, this patient went to this clinic and I believe she passed it for something like 14 to 21 days on water. And her lymphoma regressed and quieted, and I don't recall if she's free of any signs of this lymphoma, but when they published a follow up a few years later, she was still doing very well. That's an anecdote. It's not even a single subject study. There's no statistics that were applied to it or no back and forth, anything like that. So we can't really say it was a study. But it is an interesting starting place to start to look at how fasting can affect certain types of cancers.


[00:20:48.190] - Dr. Gordon

My next real question is about fasting in chemotherapy. And I know even Valter Longo has commented on this one too.


[00:20:56.670] - Dr. Lemanne

Valter Longo has done so much research in this space, and I follow his research carefully. One of the studies that his group did, along with a wonderful oncologist named Tanya Dorff, had to do with patients on a chemotherapy regimen that included a drug from the Platinum family. And there are several of those. There's carboplatin, oxaloplatin, cisplatin. And patients who were on one of those drugs for cancer had a very nice response to fasting in that the measures of immune system damage were less if those patients fasted for 24 hours before and 24 hours after their chemotherapy infusion, exactly those times. So that's a 48-hour fast altogether. They weren't eating, of course, during the infusion itself. One of the things that that study looked at was also was 24 hours of fasting enough and was 72 hours better? And it turned out that 48 hours was pretty much the sweet spot. 24 hours of fasting didn't really get anything done. Those patients that fasted for 24 hours looked pretty much the same in terms of DNA damage in their blood and immune system compared to those who weren't fasting at all. So that wasn't enough. 72 hours,


[00:22:07.980] - Dr. Lemanne

Those patients, they actually, on paper, looked like they did a little bit worse overall than the patients who did 48 hours, although they did much better than the 24 hours group. So 48 hours was the sweet spot in that very nice study from about seven or eight years ago.


[00:22:20.590] - Dr. Gordon

Now, what you told me originally, or what I've carried forth, that patients have less side effects from the chemotherapy. 


[00:22:28.820] - Dr. Lemanne

Observational studies, retrospective studies show that patients will report fewer side effects, less nausea, less fatigue with fasting, and they do have some side effects. The side effects are minor from the fasting itself, and that's basically light headedness and a little bit of temporary weakness.


[00:22:41.850] - Dr. Gordon

Which seems to come up as a theme here. That something to watch out for when you fast.


[00:22:45.800] - Dr. Lemanne

Yes, especially during that first day. And if you are choosing to fast with chemotherapy you certainly want to get the permission of your oncologist and hopefully your oncologist is familiar with these studies and is supportive; more and more oncologists are even the University of California, San Francisco now has online a page about fasting with chemotherapy.


[00:23:05.200] - Dr. Gordon

Oh, that's great.


[00:23:05.840] - Dr. Lemanne

I think it's becoming more and more accepted by oncologists who are keeping up with things, which is a hard thing to do oncology it is hard to.


[00:23:12.460] - Dr. Gordon

Keep in any field.


[00:23:13.620] - Dr. Lemanne

It is, yeah. So be nice to your doctors.


[00:23:18.030] - Dr. Gordon



[00:23:18.370] - Dr. Lemanne

Do enlighten them on this topic if you wish to proceed with fasting and get their permission and buy in.


[00:23:22.910] - Dr. Gordon

So that UCSF page is a great resource to it isn't just from this random doctor I heard on a podcast.


[00:23:29.660] - Dr. Lemanne

Well, this random doctor did actually go give a couple of talks that's fasting and I believe so did Dr. Dorff. And so they've been exposed to it and the word's getting out. So if you've had one cancer, your risk of having another cancer is higher than the general population and certain cancers correlate more with a second cancer than do others. So for instance, Hodgkin's lymphoma, especially if it's treated with radiation, those patients can later be at risk for breast cancer if their chest was radiated for the Hodgkin's lymphoma. Certain types of breast cancer, lobular breast cancer may be associated with an increased risk of lifetime breast cancer in the remaining breast or the other breast. More lobular breast, any kind of breast cancer. Invasive lobular cancer is possibly associated with an increased risk of any type of breast cancer in the future. It's just a marker for susceptibility to breast cancer.  And then there are certain genetic predispositions. We think that all of these things can be at least partially addressed by keeping the metabolism in good shape, and fasting is certainly one tool to do that. And so I would say to someone who's had cancer, once that's in the background and you finished your treatment and your health has returned, you want to go and look at the prevention side of things.


[00:24:45.530] - Dr. Lemanne

And I would say that if your doctor agrees, then once or twice a month, a 24 hours fast, a slightly longer fast once or twice a year and occasionally a very long fast, five to seven days every few years, might be something you'd want to look into if you and your doctor decide it's safe for you.


[00:25:01.250] - Dr. Gordon

We're experimenting you're experimenting with both fisetin and rapamycin. And we know that the ways in which they benefit us is by being a fasting-mimicking substitute not a diet itself, but just an intervention that has that benefit. Do you recommend, do you use with your patients at all fisetin or rapamycin in the treatment or secondary prevention of cancer?


[00:25:25.530] - Dr. Lemanne

Yes, I have patients who are using rapamycin in hopes of delaying aging and aging is a proximal cause of cancer. So in that sense, yes.


[00:25:36.560] - Dr. Gordon

Say that again right.


[00:25:37.820] - Dr. Lemanne

Aging is a proximal cause of cancer.  And dementia.


[00:25:40.910] - Dr. Gordon

Throw that in death. But what we want to do is be like the salmon from the ocean who live a fantastic life, swim upstream with full vigor, have a great night on the town, and die in good health.


[00:25:56.440] - Dr. Lemanne

I think they have sex once in their life, and that's the night, right?


[00:25:59.360] - Dr. Gordon

I think they do it more than that, but maybe I'm wrong, but we want to have a really good life up until the time we die. And aging in general, for most people, puts them at risk for dementia and cancer. So you're talking to these patients, and they are at risk for a recurrence


[00:26:19.560] - Dr. Lemanne

Yes. Patients who've had several cancers, they are at high risk of having another one and improving their healthspan and possibly their lifespan. I mean, rapamycin is associated with the lifespan, and so is fasting. Fasting is associated with improvement in lifespan. Those are important things to understand and to implement. When you can safely fasting for a lot of people, for instance, you, may actually decrease quality of life. In that sense, it might not be worth it if it doesn't increase your healthspan. In other words, if you're feeling crappy because you're fasting, that might not be the way you want to approach aging damage. I'm really looking forward to the research that sorts all of this out. And, yes, I think any of us would want a pill as opposed to doing the hard work of fasting. There is probably a propensity to have fasting be easy or hard for certain people. I'm not positive about that. I think that it may not be true, and perhaps that's just a way for people to say, well, it's harder for me than you, so you do it. And I don't know.


[00:27:15.870] - Dr. Gordon

No, you can call me a wimp. Just do it. Just call me a wimp.


[00:27:19.850] - Dr. Lemanne

No, I really think it may be harder for you, and for other people, but I do recall that it was harder for me at the beginning, and I got better at it. I should say, my enzymes seem to have gotten a little better, and there are times where I will start a fast and just abort it because it's not going well. It's too hard, something's wrong, and I'll just let it go.


[00:27:37.720] - Dr. Gordon

I think it's so important to pay attention to your body. Yes. I want to go on a big, long hike, run, swim, whatever. Today? No, today is not a good day, back out of the pool. Yeah, that's great. So my mind is swimming. Do you have several ways you could sort of sum this up in a few good takeaways for people to walk home with?


[00:27:53.820] - Dr. Lemanne

Yes. For prevention of cancer or after recovery from cancer, it's likely a good practice to incorporate fasting with your physician's permission, into your life. And 13 hours overnight, I think is reasonable and safe for just about anyone. Of course, check with your physician to make sure. But 13 hours overnight is probably how we were built to live in terms of fasting. And that means no calories, no after-supper snack. Finishing supper early is probably safer in terms of health than finishing supper at eight o’clock or later. Fasting 24 hours a couple of times a month may be a good idea for basically healthy people as is fasting 48 to 72 hours a couple times a year for healthy people. And consider a longer fast, especially if you're having some nagging health problems that you think might be improved by fasting: obesity, hypertension, possibly coronary artery disease. Again, check with your doctor. These are some things that may benefit from periodic fasting and longer fasts. Keep an open mind about this and follow the research. The animal studies are very, very clear. Fewer calories, better, in terms of longevity. We didn't talk about this, but actually there are some animal studies that show that in cancer you can turn some cancers that are absolutely incurable into curable cancers with treatment.


[00:29:14.120] - Dr. Lemanne

If you add fasting to that treatment.


[00:29:16.010] - Dr. Gordon

Is it a cancer that's also seen in humans?


[00:29:18.040] - Dr. Lemanne

I believe it was lung cancer in these animals, but I'm not positive.


[00:29:21.410] - Dr. Gordon

Some of those are really doable for anybody. Even I can do a 24-hour water only fast. But the 13-hour overnight fast is really easy if you set your mind to it.


[00:29:34.250] - Dr. Lemanne

And another thing. If you enter a fast after a few days of being on a ketogenic diet a ketogenic diet that uses fat for energy instead of carbohydrate or protein metabolism. And you can get into ketosis by eating mainly fats and almost no carbohydrates and very little protein. Or you can get into ketosis by burning your own fat because you haven't eaten for a few days. The fasting is basically the ketogenic diet on steroids. To maintain muscle mass during a fast—you don't have to worry about it if it's 24 hours, but if it's more than 24 hours, you do need to worry about losing lean muscle mass—if you go into ketosis several days before you start your fast, that process of lean muscle loss seems to be abrogated. So I do a ketogenic diet for two or three days before I go into a long fast, and then finish up that fast with another day or two of ketogenic diet to preserve my muscle mass. And I will do some light weight training, especially with my thighs. The quads seem to be particularly susceptible to atrophy in older people and people who are not getting enough calories.


[00:30:35.090] - Dr. Lemanne

So that may prevent that process as well.


[00:30:38.140] - Dr. Gordon

So if I want to go on a fasting program and be really, really brave and do it for three days but I don't want to lose any muscle because I'm training and I don't want to lose muscle anyway, if I get myself on a good ketogenic diet for three days beforehand, I'm less likely to lose muscle mass when I then fast for three days. 


You have been listening to the Leman Gordon Podcast where Docs talk shop.


[00:31:08.660] - Dr. Lemanne

For podcast transcripts, episode notes and links, and more, please visit the podcast website at docs Happy Eavesdropping everything presented in this podcast is for educational and informational purposes only and should not be construed as medical advice. No doctorpatient relationship is established or implied. If you have a health or a medical concern, see a qualified professional promptly.


[00:31:44.940] - Dr. Gordon

We make no warranty as to the accuracy, adequacy, validity, reliability, or completeness of the information presented in this Podcast or found on the podcast website.


[00:31:57.010] - Dr. Lemanne

We accept no liability for loss or damage of any kind resulting from your use of the Podcast or the information presented therein. Your use of any information presented in this podcast is at your own risk.


[00:32:11.570] - Dr. Gordon

Again, if you have any medical concerns, see your own provider or another qualified health professional promptly.


[00:32:18.340] - Dr. Lemanne

You must not take any action based on information in this Podcast without first consulting your own qualified medical professional.