Can Fasting Heal a Bacterial Infection?

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DISCLAIMER: If you have a bacterial infection you need to see your doctor right away. What follows is not medical advice. It is an account of my experiences. Please be smart when dealing with your biological life. OK? Great. Read on!

I noticed that since I started my keto journey, which includes intermittent fasting, my immune system seemed to be compromised a bit. I was getting more colds. In 2016 – after being keto for 4 months – I came home from Belgium with a whopper of a virus that lasted all summer. I am a primary vocalist for my band, Franklin Brothers, and I couldn’t sing. I thought there might be a connection but I let it slide. On the bacterial side, cuts and scrapes that should have healed were getting infected and requiring antibiotics to heal. Knowing what I know about antibiotics, this scared me a bit. The last two scrapes I had turned into cellulitis, a painful (then itchy) condition where the skin gets infected and spreads. It’s not good.

About 10 days ago I burned myself on the underside of my wrist. It blistered and reddened. Even though I covered it with antibiotic cream and gauze, it got infected and turned into what looks and feels like a cellulitis. Great. More antibiotics.

As a side note, I got a new doctor this year, Dr. Ken Berry. He’s a family doctor in rural Tennessee. He wrote a book called Lies My Doctor Told Me, which I read, and it rang true. He has a program where you can come see him once in person, get blood work done, and so long as you’re not on medications or have conditions that require constant in-person monitoring, he can be your GP and provide care remotely. Having a bad experience with my local doctor who refused to do the research to come out of the dark ages, that was a no-brainer. Anyway, my blood test showed low testosterone.  Dr. Berry informed me that when T is low, skin infections take longer to heal. A little research confirmed this. So, I immediately started on a testosterone gel to get my levels back to normal.

Back to the infection. Having this nagging feeling about my immune system being affected by fasting I did some research and I found what, on the face of it, look like two studies with opposite findings.

This article cites a study that introduced fruit flies to a fungus that activated similar genes in humans which affect stress and immunity. It did indeed extend their lives, however it made them more susceptible to infections. Now, bear in mind, this was done on fruit flies. They jump to a couple conclusions. 1) intermittent fasting will have the same effect as this fungus, and 2) this outcome will be the same in humans as in fruit flies.

The second article cites a study at Yale in which mice were given viral or bacterial infections, then either fed or fasted. When fed, the ones with a viral infection survived and the ones with the bacterial infection did not. When fasted, the results were reversed. Those with a viral infection did NOT survive, and those with a bacterial infection did. The Atlantic did a story on this same study, with a bit more editorial. Here’s a quote from it:

“In principle, one day a doctor could give a diagnosis along with a specific dietary recommendation. That could speed recovery and limit the global crisis of antibiotic overuse.”

Last year I came across this article citing a study in which extended fasting for just three days seems to completely regenerate the immune system, which has a net positive effect on bacterial infections.

As I said: on the surface, the findings of the first and third studies seem to contradict each other. Or do they?

Intermittent fasting is different than extended fasting. If you fast for 23 hours, the process of autophagy hasn’t had time to complete. It’s only by fasting for three days that your immune system seems to regenerate itself. That sounds like another phenomena which happens when you don’t complete a course of antibiotics. The bacteria develop a resistance to it. Knowing what I know about resistance and how it happens makes me think there may be something similar happening here. This, however, is just a guess.

If it it’s true that intermittent fasting will make you more susceptible to infection (which seems to be the case with me) and extended fasting can have a positive effect on your immune system which will help fight a bacterial infection, then I should do an extended fast and see what happens to my cellulitis.

Now, before you say “that’s crazy, Carl. You could die!” I ran this idea by my doctor and he agreed I should try it – with the caveat that we should watch it every day. If it gets worse, we stop the experiment and get the antibiotics. A few days isn’t going to make any difference. If it gets better, however, that means something profound. I will have healed an infection that would otherwise have required antibiotics.

There is a confounder in my experiment, however. I started taking the testosterone on day two, which is helping my body heal itself. In order to truly test this, I would have to have had normal T when I got the infection, and then fasted. However, my goal here is to get rid of the infection without antibiotics. If that happens, I’m happy for now, and we can file this under “needs more research.”

On top of fasting, I found that spraying the infected skin in the shower with hot water, as hot as I could stand, had a strange but pleasurable feeling, like you get when you scratch an itch. It also seemed to take the itch away. I don’t know why this is, but I did it twice a day to control the itch. I also applied Cetaphil, a skin moisturizer, to it every day.

Ok, let’s look at some pictures, shall we? This is the first picture I took on May 11, 2018: The day I started fasting. By this time the wound had healed but it was still very sore.

I had actually stopped eating the day before, May 10th, but I had coffee with heavy cream twice in the day. I usually do this to ease into a fast. So, this was technically after one day of no food, but heavy cream. I do have 2 drinks of non-carb alcohol (whiskey) in the evening. I read a study that indicates moderate alcohol consumption activates autophagy. Hey, as long as it doesn’t stop it, I’m all in!

Here’s the picture from day two: May 12:

Day two I was all in. No food. Just black coffee, water, salt, and supplements. I also took my first dose of testosterone.

Here’s a picture from day three. This is when I really noticed it was starting to fade.

And here we are at Day 4. Practically gone.

To summarize, I had low testosterone. I was doing a ketogenic diet with IF. I was getting more infections than normal. The third time I decided to intervene with testosterone therapy and an extended fast. I don’t know to what extent each of these interventions helped, but the undeniable result is that I cleared up a bacterial infection that normally would have taken a course of antibiotics, and that makes me happy.

Dr. Jason Fung from the IDM Program commented: “That’s super interesting Carl. There is no science one way or the other, but to me it makes sense. Whenever we get sick (flu etc.) we stop eating. It’s a natural reaction, so it must be protective. Fasting locks down glucose, and forces us to use fatty acids for energy, which the bacteria are unable to use. You are basically starving the bacteria out.”

I’m still not convinced it was the fasting 100% and not the testosterone.

On Day 4 I wanted to get a bit more focused in the experiment. I broke my fast at 3PM, and ate quite a lot of fatty food. I also decided that the next day I would NOT apply the testosterone gel, but I WOULD get back to fasting. The next morning it did seem to be a bit more red, itchy, and I could feel a twinge of pain that wasn’t there the day before. Here’s a photo from day 5:

You can see that it’s a bit more red.

I am going to do another longer fast (at least 3 days) without the Androgel testosterone therapy, and post my pictures here every day by updating this blog post.

Day 6 – No Androgel. Back to fasting. As you can see it looks a little more red. Yesterday I fasted all day with just a couple zero-carb drinks in the evening. Now this is getting interesting.

Here we are at day 7, or more precisely, after 2 days of a resumed fast with no testosterone. It looks better than it did yesterday, and that’s promising.

Day 8, or 3 days fully fasted (had a break in the middle there) without testosterone. Still continuing to heal.

Again, if you have a bacterial infection, you should talk to your doctor immediately.

Carl Franklin

Notable Replies

  1. Jason Fung’s response to me by email: “That’s super interesting Carl. There is no science one way or the other, but to me it makes sense. Whenever we get sick (flu etc.) we stop eating. It’s a natural reaction, so it must be protective. Fasting locks down glucose, and forces us to use fatty acids for energy, which the bacteria are unable to use. You are basically starving the bacteria out.”

  2. Carl, pretty cool, though without more samples and controls it doesn’t show causality. Maybe it was just lucky timing - fasting on the day the infection had run its course and was ready to clear. I suggest some more experimentation to help nail this down. We could start by burning your other wrist similarly and giving it about 10 days to reach a similar state of inflammation. Then instead of fasting do the exact opposite, eat a bowl of sugar. If it starts to appear gangrenous and smells putrid it would provide strong evidence for a diet rot hypothesis!

  3. I got a text from Karen Mangiacotti today. She developed a cellulitis and is going to try fasting for a few days before going for the antibiotics. Hers may be a more pure experiment. I asked her to take a picture of it every day.

  4. I just updated the post (scroll up) with today’s picture. It’s clearly getting better with fasting alone. I’m going to continue to fast without testosterone. Dr. Berry says it takes three to five days for the T to completely leave your system.

    One of the side benefits of this fast is weight loss. I’ve hit a new low weight since going keto. 284, or 82 pounds.

    So, today is a very good day. I may celebrate tonight with some salt, butter, and a Maker’s on the rocks.

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