Intermittent Fasting and Chemotherapy -

Intermittent Fasting and Chemotherapy

Intermittent fasting is the period of voluntary fasting and resuming with healthy eating over a given period. It could be done on a regular basis with 16 to 18 hours of fasting and a window period of 8 and 6 hours respectively. Alternate day fasting or periodic fasting is also common.

How does intermittent fasting help you while undergoing chemotherapy?

● Growing preclinical evidence shows that short-term fasting (STF-24 to 60 hours), protects from toxicity while enhancing the efficacy of a variety of chemotherapeutic agents in the treatment of various tumor types. STF improves stress resistance of healthy cells, while tumor cells become even more sensitive to toxins, as there is shortage of nutrients to satisfy their needs which can reduce their high proliferation rates and reduces their resistance to the stress such as chemotherapy.


● Chemotherapeutic agents inflict oxidative stress and DNA damage upon healthy cells, which are underlying mechanisms of toxicity. STF dampens oxidative stress in healthy cells by down-regulating metabolic rate and increasing scavenging of reactive oxygen species.
● STF brings about an “anti-Warburg effect”, meaning it decreases the uptake of glucose by the cancer cells and hence can help in bringing out apoptosis.

It’s also important to note that overconsumption after a STF period might accelerate tumor growth, due to high glucose conditions and increased glycolysis.

According to NCBI however, STF might be only feasible in chemotherapeutic regimens characterized by:

1) Bolus infusions on one day, to keep the fasting period short
2) A long interval between two cycles, to ensure sufficient recovery time between cycles
3) Low dose or no use of corticosteroids, to avoid hyperglycemia, which might interfere with the benefits of STF

Side effects of STF:

According to NCBI, STF has only mild side effects, such as headaches, dizziness, nausea, weakness and short-term weight loss.

Therefore, STF is a promising strategy to enhance the efficacy and tolerability of chemotherapy in cancer patients, especially as STF is an affordable and accessible approach and is potentially effective in a wide variety of tumors.

Who is not a suitable candidate for intermittent fasting?
Patients at risk for malnutrition, sarcopenia or cachexia may not be candidates for STF, as it may be unsafe to further limit nutrient intake in these patients for even a short time.
A word of precaution:
If you are someone who is considering IF along with the treatment, please discuss its pros and cons with your oncologist and do it under the guidance of an nutritionist/ dietitian who can help you achieve the desired results from intermittent fasting and at the same time avoid loss of muscle mass and nutrient deficiency.


Tags: Intermittent, voluntary fasting, healthy eating, 16 to 18 hours of fasting, window period of 8 and 6 hours, alternate day fasting or periodic fasting, chemotherapy, short-term fasting (STF-24 to 60 hours), chemotherapeutic agents in the treatment of various tumor types. STF improves stress resistance of healthy cells, oxidative, scavenging of reactive oxygen species, anti-Warburg effect, apoptosis, Side effects of STF, malnutrition, sarcopenia or cachexia, precaution, pros and cons, guidance of an nutritionist/ dietitian, avoid loss of muscle mass, nutrient deficiency, cancer, cancer treatment