Short-Term Fasting Can Reduce Unpleasant Side Effects of Chemotherapy

French author and martial arts expert Fred Evrard beat borderline Stage 4 colon cancer in just four short months using a combination of conventional natural treatments – including intermittent fasting. Originally advised by his oncologist that he would need to undergo 24 chemotherapy treatments, followed by radiation and surgery to remove the 4-inch tumor in his colon, Fred was told that even with all that, his prognosis was 50% chance of survival.

He opted instead for alternative cancer treatments, including a judicious approach to both short- and long-term fasting. After two months, the tumor had shrunk in half. Fred says that when the pain became unbearable, he agreed to a total of three chemotherapy treatments to help reduce the size of the tumor even faster, then resumed his totally natural treatments and self-restricted diet.

Before that first chemo treatment, Fred fasted for three days – the day prior, the day of, and the day following. He was surprised to experience none of the anticipated side effects (nausea, vomiting, and fatigue). For the second chemo treatment, Fred opted to eat a small amount each day, after which he experienced the intense nausea and vomiting and fatigue that are so common. For his third chemo treatment, he chose again to fast before, during, and after the treatment. As with the first treatment he received, there were again NO unpleasant side effects.

Hold The Sugar

Fred said that during his chemotherapy treatments, he and the other patients would often be offered soda and cookies – and he wanted so badly to tell everyone in the room, “Don’t eat them! Sugar feeds cancer!” But instead, he simply quietly refused the snacks.

Doctors Were Astonished

Following his initial cancer diagnosis, Fred said he spent the first three days simply trying to recover from the shock of hearing the devastating news, but he pulled himself together and researched his options thoroughly. He decided it made sense to drastically cut off the food supply to the cancerous cells growing within his body — and chose to fast for 21 days. During this 21-day period, he had purified water only, with a once-a-week shot of fresh wheat grass juice. After that initial fast, his tumor had shrunk by 50%.

Following the initial 21-day fast, Fred ate one meal a day and followed a strict ketogenic diet. He said that his intestines were so inflamed that he could not tolerate any vegetables, grains, or carbs, and so his diet consisted mainly of grass-fed, grass-finished beef. Eventually, he was able to tolerate juiced vegetables, and carefully added those to his diet.

His conventional doctors were astonished when an MRI showed that after only four months, the tumor was completely gone.

You can learn more about Fred’s fight against cancer in his book, How my Immune System beat cancer: Fasting, Juicing, Ketogenic diet, Breathing, Exercise, Meditation and other non-toxic therapies.

Why Does Short-Term Fasting Reduce Chemo Side Effects?

Fasting deprives cancer cells of everything they need to grow and proliferate. Fasting also promotes apoptosis, or cell death and drastically reduces the chance of metastasis (spread of cancer).

The Proof

A landmark study involving 131 patients with stage 1 and stage 2 breast cancer showed that fasting had a pronounced effect on tumor response of the patients. In fact, it was three times more effective in the fasting group compared to the control group.

A case study series from the University of Southern California (USC) reported “a decrease in chemotherapy-induced side effects, including fatigue, weakness, vomiting, and diarrhea, when chemotherapy was combined with short-term fasting compared to chemotherapy alone.” (source: Paul Zhang, MD, PhD)

A study published in the journal Chemotherapy (2020) showed that “fasting may reduce nausea, vomiting, diarrhea, abdominal pain, and mucositis that were almost absent in the reports from the 10 patients that fasted before or after chemotherapy, while almost 1 of these symptoms was reported by 5/6 patients who received normal feeding.”

A randomized cross-over trial performed by researchers from Berlin, Germany, evaluated the effect of short-term fasting on chemo patients. Half of the patients fasted 36 hours prior to chemo and 24 hours afterward and the other half consumed a normal Mediterranean diet. The researchers’ conclusion? Short-term fasting led to a better tolerance of chemotherapy and reduced fatigue following the treatment.

And finally, according to Fasting During Chemotherapy (June 29, 2022), “cycles of starvation (fasting) were as effective as chemotherapy drugs in delaying progression of mammary tumors in mice in one study. In addition, starvation plus chemotherapy increased the effectiveness of the treatment.”

Your Body, Your Choice

I know that when you first hear those dreaded words, “You have cancer,” you may feel as if a rug has been pulled from underneath you.

I get it. My world crumbled when I got that phone call from my doctor. My perfect world – my wife, our baby daughter, our home and the businesses we had built, everything that I was looking forward to in life – came crashing down. (Chapter 2 of I Used to Have Cancer: “The Words No One Wants to Hear.”

What I learned in the months and years following that dreaded diagnosis is that I had more OPTIONS than I first realized. Now I tell others that it only makes sense to take some time to explore, research, and weigh all the options available, not just the ones provided by your conventionally-trained doctor. A second or even a third diagnosis is also a good idea. And spending some time exploring how other people in your situation have beat the odds can be an enormous help. How did they do it? Is it something you can incorporate into your daily regimen? I believe that if I and others like me can beat cancer, then you can, too.

And remember that there’s not just one path back to health. What works for one person may not work for another. But if you’ll take a deep breath and explore all your options, you might just be surprised at the results.

Check out the totally free cancer survivor stories and interviews from many of the leading cancer expert practitioners from all around the world that you’ll find on my website.


James Interviewing Others



Evrard, Fred. How my Immune System Beat Cancer: Fasting, Juicing, Ketogenic Diet, Breathing, Exercise, Meditation and Other Non-Toxic Therapies. January 12, 2021.

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