Does Fasting Kill Cancer?

Check out this answer from Consensus:

Fasting, particularly in the form of intermittent fasting and fasting-mimicking diets, shows potential as an adjunct to conventional cancer therapies. It may enhance the effectiveness of treatments, reduce side effects, and improve patients’ quality of life. However, more robust clinical evidence is needed to fully understand its role in cancer treatment and to develop standardized guidelines for its implementation.

Fasting has garnered significant attention in recent years for its potential role in cancer treatment. The concept revolves around the idea that fasting can create a metabolic environment that is less favorable for cancer cells while simultaneously protecting normal cells from the adverse effects of conventional cancer therapies. This article explores the current scientific evidence on whether fasting can kill cancer, focusing on various fasting regimens and their impact on cancer treatment and prevention.

Mechanisms of Fasting in Cancer Treatment

Several studies have investigated the underlying mechanisms through which fasting may influence cancer cells and enhance the efficacy of cancer treatments.

Differential Stress Resistance

Fasting induces a state of differential stress resistance, where normal cells enter a protective mode, while cancer cells, which are often unable to adapt to nutrient deprivation, become more susceptible to treatment-induced damage. This phenomenon has been observed in both preclinical and clinical studies1 2 7.

Metabolic Changes

Fasting leads to significant alterations in growth factors and metabolite levels, such as reduced insulin, IGF-1, and glucose levels, and increased ketone bodies. These changes create an environment that hampers cancer cell growth and survival while promoting the regeneration of normal tissues2 8.

Enhanced Chemotherapy and Radiotherapy

Fasting has been shown to enhance the effectiveness of chemotherapy and radiotherapy by increasing oxidative DNA damage in cancer cells and promoting apoptosis. Normal cells, on the other hand, are better able to repair damage and survive1 3 5.

Clinical Evidence

While preclinical studies provide a strong foundation, clinical evidence is crucial for validating the efficacy and safety of fasting in cancer treatment.

Chemotherapy

Several clinical trials have explored the impact of fasting on chemotherapy outcomes. For instance, a study on gynecologic malignancies found that short-term fasting improved patients’ quality of life and reduced chemotherapy-related side effects without increasing weight loss or hospital admissions7. Another study highlighted the potential of fasting-mimicking diets (FMDs) to enhance the effectiveness of chemotherapy and reduce its toxic side effects2 9.

Radiotherapy

Research suggests that caloric restriction and specific diets, such as ketogenic diets, can increase the responsiveness of tumors to radiotherapy. These dietary interventions may stimulate an acute anticancer immune response and promote the accumulation of oxidative lesions in cancer cells3.

Intermittent Fasting

Intermittent fasting has shown promise in reducing the risk of certain types of cancer and improving the quality of life for cancer patients. However, the evidence is primarily based on animal studies, and more well-designed clinical trials are needed to confirm these findings4 6.

Limitations and Future Directions

Despite the promising results, there are several limitations to the current body of research. Most studies are preclinical or involve small sample sizes, making it difficult to generalize the findings to larger populations. Additionally, the heterogeneity in fasting protocols and cancer types studied adds to the complexity of drawing definitive conclusions1 4 6.

Future research should focus on large-scale, randomized clinical trials to better understand the potential benefits and risks of fasting in cancer treatment. Standardizing fasting protocols and exploring the long-term effects of fasting on cancer recurrence and survival rates are also essential.

Does fasting kill cancer?

Mathieu Laplante has answered Extremely Unlikely

An expert from Université Laval in Obesity, Cell Biology

Fasting does not kill cancer cells. Tumours do not go away by reducing food intake. This video is pure junk, not supported by any clinical evidence. The combination of fasting with chemotherapy, immunotherapy or other treatments is proposed to represent a potentially promising strategy to increase treatment efficacy, prevent resistance acquisition and reduce side effects. However, fasting per se does not kill cancer cells.

Eating less will reduce obesity and chances of developing obesity-related diseases such as insulin resistance, type 2 diabetes, and cardiovascular diseases. Reducing food intake and improving the quality of the food ingested may reduce the chances of developing a cancer. However, if you do have a cancer, reducing food intake won’t cure you.

Does fasting kill cancer?

Marco Corazzari has answered Unlikely

An expert from University of Eastern Piedmont in Oncology

Well, this is a very interesting topic and it is not easy to answer in few words but yes, frequently solid cancers prefer sugar to get energy, instead of lipids or other complex molecules we introduce by eating. It is also believed that a caloric restricted diet tends to lengthen life. However, unfortunately, many studies clearly indicate that fasting alone is not sufficient to kill cancer cells, but an appropriate chemotherapeutic regimen copuled to a caloric restricted/controlled diet can consistently increase the therapeutic outcome.

It is also important to keep in mind that scientists and clinicians are increasingly directed towards personalized therapy, so that each individual tends to react in a peculiar way, so each therapy must be calibrated on the individual.

Does fasting kill cancer?

Nighat Y Sofi has answered Unlikely

An expert from Banasthali University in Breast Cancer, Nutrition

Does fasting kill cancer?

Fasting has a protective effect against cancer due to the inhibition of the nutrient-sensing signals and pathway in normal cells and its role in adaptive cellular responses that reduce oxidative damage and inflammation, achieving cellular protection (1). However, the question that fasting kills cancer is not applicable as cancer is a combination of complicated changes which arises from a set of modifiable and non-modifiable risk factors.

Fasting in combination with standard treatment procedures has provided significant results in terms of treatment outcomes. There are few in vitro research studies available on the role of fasting in decreasing the progression of cancer. A study in mouse model with breast cancer following two 48-h fasting cycles resulted in an arrested tumor progression (2).

Research studies have concluded that fasting immediately before, during, and after chemotherapy infusion potentiates the anticancer effects of the treatment while reducing side effects (3-5). Research studies involving fasting before or after chemotherapy in women with breast cancer concluded that fasting 24 h before and after each chemotherapy infusion was well tolerated and decreased side effects of chemotherapy (6-7). Another research study on duration of fasting concluded women fasting 13 or more hours overnight suffered fewer cancer relapses compared with those fasting 12 or fewer hours (8) .

 The vital part to ascertain any association of fasting and its effect on cancer outcome has to be defined with caution. Prolonged fasting with an objective to enhance the long term disease free survival might compromise the nutritional status of the individual affecting the treatment prognosis and overall well being. This is why defining fasting and duration has to be precise for significant outcome. However, more research is needed to shed light and draw concrete conclusions on the topic defining fasting and its role in cancers of different types and origin.

 References:

1. Matsubara S, Ding Q, Miyazaki Y, et al. mTOR plays critical roles in pancreatic cancer stem cells through specific and stemness-related functions. Sci Rep. 2013; 3:3230.
2. Lee C, Safdie FM, Raffaghello L, et al. Reduced IGF-I differentially protects normal and cancer cells and improves chemotherapeutic index in mice. Cancer Res 2010;70:1564-1572.
3. Lee C, Raffaghello L, Brandhorst S, et al. Fasting cycles retard growth of tumors and sensitize a range of cancer cell types to chemotherapy. Sci Transl Med 2012;4:124ra27.
4. Shi Y, Felley-Bosco E, Marti TM, et al. Starvation-induced activation of ATM/Chk2/p53 signaling sensitizes cancer cells to cisplatin. BMC Cancer 2012;12:571.
5. Raffaghello L, Lee C, Safdie FM, et al. Starvation-dependent differential stress resistance protects normal but not cancer cells against high-dose chemotherapy. Proc Natl Acad Sci USA 2008;105:8215–8220.
6. De Groot S, Vreeswijk MP, Welters MJ, et al. The effects of short-term fasting on tolerance to (neo) adjuvant chemotherapy in HER2-negative breast cancer patients: A randomized pilot study. BMC Cancer 2015;15:652.
7. Dorff TB, Groshen S, Garcia A, et al. Safety and feasibility of fasting in combination with platinum-based chemotherapy. BMC Cancer 2016;16:360.
8. Marinac CR, Nelson SH, Breen CI, et al. Prolonged nightly fasting and breast cancer prognosis. JAMA Oncol 2016;2:1049–1055.

Does fasting kill cancer?

Vicente A Benites-Zapata has answered Unlikely

An expert from Universidad San Ignacio de Loyola in Epidemiology, Biostatistics, Endocrinology, Internal Medicine

There are several cancers associated with insulin resistance and impaired blood glucose levels. In a meta-analysis, a positive association between glycemia levels and cancer risk is evidenced (https://www.ncbi.nlm.nih.gov/pubmed/25526881). However, the authors of this publication stated that the underlying biological mechanisms remain to be elucidated but their subgroup analyses suggest that the insulin- IGF-1 axis does not fully explain the association. There is no more, evidence in this regard. So, thinking that fasting could be the solution to cancer is a wrong message. What should be done to encourage the population to do physical activity and eat healthy.