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  • Clare Reed CBT Therapist

To Fast or Not to Fast During Chemo

To fast or not to fast? That is the question I get asked a lot by my CBT for Cancer clients leading up to their chemotherapy and one I also asked my own Oncologist. During my Cancer treatment I had a fantastic research tool at my disposal, my mother. She loves researching and she came up trumps with the fasting research for me, just before I started chemotherapy.

To Fast or not to Fast During Chemo
To Fast or not to Fast During Chemotherapy

What is Fasting all About

This year fasting is now all the rage in California, particularly with the tech geeks, who think this is super cool! But in 2017 it was barely mentioned. In a way I wish it wasn’t trending in the media, as there is a lot of misinterpretation of benefits and some very extreme cases of fasting for weeks at a time that I in no way advocate. This is not a competition after all. But if we look at it from a chemotherapy protocol perspective, fasting is an interesting concept.

The main research for fasting during chemo in recent years was by a Doctor Valter Longo and his team in the USA who initially used his little mice to experiment on. He trialled them fasting on different days and time frames whilst giving them chemo, poor little things. But the results showed a marked improvement in white blood cell preservation and an increase in cancer cell kill off, whilst preserving healthy cells. He then duplicated this experiment on humans with cancer with similar results. In lay-persons speak, while fasting the good healthy cells go into hibernation while a fast is taking place and the old, washed up, cells, along with the growing cancer cells, get eliminated. Cancer cells like to gorge on anything they can get their hands on, to enable their growth. During a fast, as soon as the chemo is administered, they go at the chemo like kids at a party buffet seeking out the chocolate and crisps. Hence why the cancer cells die faster in a fasting environment because all they get to eat is chemo!

My Fasting Experiment
My Fasting Experiment

My Chemotherapy Fasting Experiment

My first three rounds of chemo were held once every three weeks when ‘FEC’ chemo was administered, famous for hair loss and nausea – oh joy! I did indeed lose my hair after the second infusion and I was nauseous. I didn’t fast for the first chemo infusion I wanted to see what au-naturel looked like. It wasn’t pretty. I had severe nausea for three days and was bed ridden for those days too, wishing the world would stop spinning. I started the fasting with the second infusion. 48 hours before chemo and the day of chemo, 3 days in total. Funnily enough, considering I had never fasted in my life, this was a breeze. I had a couple of tummy rumbles the first evening but after that my body seemed to enter a zen like state of acceptance.

I did drink lots of water on fasting days. The day before chemo 2 litres of water, plus a couple of herbal teas. 3 litres of water on chemo day and 2 litres the day after. This time round I still got nauseous but seemed to start recovery in 2.5 days instead and sprung out of bed on the 4th day after chemo feeling vibrant and alive. The following infusion was tougher, as my car broke down on the way to the hospital. I had to put off the infusion for another day. I spent 4 days not eating! This was way tougher than I expected. The recovery after this infusion was faster. I had nausea again for a couple of days and then came back to life on the third day after chemo – result!

The fasting experiment became very interesting when I progressed to stage 2 of chemo and on to the once a week for 12 weeks infusion of Paclitaxel. Paclitaxel is notorious for more hair loss, bone pain, nose bleeds, neuropathy in hands and feet and finger and toe nails dropping off – nice! So as this chemo infusion was weekly I had to psych myself up for fasting every week. I dropped the fast to the day before and the day of chemo, to just 2 days. This was naturally a breeze compared to 3 days fasting on FEC. I was amazed with the results and my Oncologist was amazed with my white blood cell and neutropenia counts, they barely dropped below 4.0. I never needed any horrid pain inducing Neulasta injections. He was amazed because on weekly Paclitaxel he normally sees a progressive decrease in white blood cells over the weeks.

I had no side effects, except for not sleeping on the dreaded steroids that accompanied the chemo. Every chemo night I was wired from steroids, I couldn’t stop my brain whirring. But I had no neuropathy, no nail problems, no nausea, no nosebleeds and no fatigue. A great side effect was during my chemo I dropped 2 stone in weight through my plant-based diet, exercise and fasting regime and levelled out at 8.5 stone half way through my Paclitaxel treatment. Normally people gain weight on weekly Paclitaxel due to the steroids. I had always been 8.5 stone until my mid-thirties. At 41 I was overweight by 1.5 stone when I was diagnosed with Triple Negative Breast Cancer, a contributing factor! Even being a couple of kilos over weight was a deadly contributing factor. With fasting I felt better than I had in the last few years, my energy levels were higher, I was figuratively bouncing along the road and into the chemo room!

Fasting Gave Me Energy
Fasting Gave Me Energy

Fasting with Others is More Fun

My Oncologist didn’t bat an eye lid when I told him I was considering fasting in our pre-chemo meeting, though he is Italian and he knew of the studies supporting fasting and chemotherapy conducted by the Italian American, Dr Longo. He said, ‘Go for it’! I don’t think he suggests it to his other patients though, the lack of integrative Oncology and health/diet programmes is sorely lacking in his office. But he was supportive. I think it was the best thing I could have done for my health in that period. I still fast one day a week now, as the benefits are addictive. My mother and my Partner joined in with a one day a week fast during my chemo in support, this made life easier - nothing beats a great team! I couldn’t let my mother shave her beautiful head of hair in sympathy with my balding head, and this was a fun compromise! She too had breast Cancer ten years go. She has also kept the fasting up and at nearly 70 years of age she has found she she can fit in her older clothes, which had got a bit tighter in the last few years, and she is feeling more energised too.

I am not an expert in fasting, I did this as an experiment, one that paid off for me. But we are all different and our health and weight are too. Naturally this isn’t recommended for people underweight at the start of treatment. If you want to explore fasting as an option during your chemotherapy run it by your Oncologist to see what they say.

I would be very interested to hear from you if you gave this a go and what the outcomes were for you so please let me know by commenting below or drop me an email.

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