I started to follow the fast diet initially to lose weight, but after reading The Fast Diet book I am very interested in the link between fasting and cancer. My father (at 63), his two brothers, and his mother (at 58) all died of cancer.
This is an excerpt from the “The Fast Diet: Lose Weight, Stay Healthy, and Live Longer with the Simple Secret of Intermittent Fasting” by Dr. Michael Mosley and Mimi Spencer:
My father was a lovely man but not a particularly healthy one. Overweight for much of his life, by the time he reached his sixties he had developed not only diabetes but also prostate cancer. He had an operation to remove the prostate cancer, which left him with embarrassing urinary problems. Understandably, I am not at all keen to go down that road.
My four-day fast, under Valter Longo’s supervision, had shown me that it was possible to dramatically cut my IGF-1 (insulin-like growth factor 1) levels and by doing so, hopefully, my prostate cancer risk. I later discovered that by doing intermittent fasting and being a bit more careful with my protein intake, I could keep my IGF-1 down at healthy levels. The link between growth, fasting, and cancer is worth unpacking.
The cells in our bodies are constantly multiplying, replacing dead, worn out, or damaged tissue. This is fine as long as cellular growth is under control, but sometimes a cell mutates, grows uncontrollably, and turns into a cancer. Very high levels of a cellular stimulant like IGF-1 in the blood are likely to increase the chance of this happening.
When a cancer goes rogue, the normal options are surgery, chemotherapy, or radiotherapy. Surgery is used to try to remove the tumor; chemotherapy and radiotherapy are used to try to poison it. The major problem with chemotherapy and radiotherapy is that they are not selective; as well as killing tumor cells they will also kill or damage surrounding healthy cells. They are particularly likely to damage rapidly dividing cells such as hair roots, which is why hair commonly falls out following therapy.
As I mentioned above, Walter Longo has shown that when we are deprived of food for even quite short periods of time, our body responds by slowing things down, going into repair and survival mode until food is once more abundant. That is true of normal cells. But cancer cells follow their own rules. They are, almost by definition, not under control and will go on selfishly proliferating whatever the circumstances. This “selfishness” creates an opportunity. At least in theory, if you fast just before chemotherapy, you create a situation in which your normal cells are hibernating while the cancer cells are running amok and are therefore more vulnerable.
In a paper published in 2008, Valter and colleagues showed that fasting “protects normal but not cancer cells against high-dose chemotherapy,” followed by another paper in which they showed that fasting increased the efficacy of chemotherapy drugs against a variety of cancers. Again as is so often the case, this was a study done in mice. But the implications of Valters work were not missed by an eagle-eyed administrative judge named Nora Quinn, who saw a short article about it in the Los Angeles Times.
I met Nora in Los Angeles. She is a feisty woman with a terrific, dry sense of humor. Nora first noticed she had a problem when, one morning, she put her hand on her breast and felt a lump the size of a walnut under her skin. After indulging, as she put it, in the fantasy that it was a cyst, she went to the doctor; it was removed and sent to a pathologist.
“The reality of your life always comes out in pathology,” she told me. When the pathology report came back, it said that she had invasive breast cancer. She had a course of radiotherapy and was about to start chemotherapy when she read about Valter’s work with mice.
She tried to speak to Valter, but he wouldn’t advise her because, up to that point, none of the trials he had run had been done with humans. He didn’t know if it was safe for someone about to undergo chemo to fast, and he certainly wasn’t going to encourage people like Nora to give it a go.
Undeterred, Nora did her own research and decided to try fasting for seven and a half days, before, during, and after her first bout of chemotherapy. Having discovered how tough it can be to do even a four-day fast while fully healthy, I’m surprised she was able to go through with it, though Nora says it’s not so hard and I’m just a wimp.
The results were mixed.
“After the first chemo I didn’t get that sick, but my hair fell out, so I thought it wasn’t working.” So next time she didn’t fast, and she was only medium sick. “I thought, seven and a half days of fasting to avoid being medium sick, this is a really bad deal. I am so not doing that again.”
So when it was time for her third course of chemo, she didn’t fast. That, she now feels, was a mistake. “I got sick. I don’t have words for how sick I was. I was weak, felt poisoned, and I couldn’t get up. I felt like I was moving through Jell-O. It was absolutely horrible.”
By the time Nora had to undergo her fourth course of chemo, she had decided to try fasting once again. This time things went much better and she made a good recovery. She is currently cancer free.
Nora is convinced she benefited from fasting, but it’s hard to be sure because she wasn’t part of a proper medical trial. Valter and his colleagues at USC did, however, study what happened to her and ten other patients with cancer who had also decided to put themselves on a fast. All of them reported fewer and less severe symptoms after chemotherapy, and most of them, including Nora, saw improvements in their blood results. The white cells and platelets, for example, recovered more rapidly when they had chemo while they were fasting than when they did not.
But why did Nora go rogue? Why didn’t she fast under proper supervision? She says: “I decided to fast based on years of information from animal testing. I do agree that if you are going to do crazy things like I did, you should have medical supervision. But how? None of my doctors would listen to me.” Nora’s self-experiment could have gone wrong, which is just one reason why such maverick behavior is not recommended. Her experience, however, and that of the other nine cancer patients, helped inspire further studies. For example, Valter and his colleagues have recently completed phase one of a clinical trial to see if fasting around the time of chemotherapy is safe–which it seems to be. The next phase is to assess whether it makes a measurable difference. At least ten other hospitals around the world are either doing or have agreed to do clinical trials.