Impact of intermittent fasting on patients with cancer undergoing chemotherapy and/or targeted therapies: a systematic review of the literature.
Level 1 - systematic review of randomized trials
Systematic review of clinical studies
PubMed 40970988 · doi:10.1007/s00520-025-09907-7
What was done
A systematic review evaluated the safety, feasibility, tolerability, metabolic effects, quality of life, side effects, and treatment outcomes of intermittent fasting in cancer patients undergoing chemotherapy and/or targeted therapies. Studies published between 1990 and March 2025 were identified and evaluated for risk of bias using a validated tool.
What was found
Nine studies were included out of 1,725 screened records, comprising 354 total patients, predominantly with breast cancer (n = 258/354). Risk of bias was rated low to moderate. Fasting was safe and feasible, but had no demonstrated effect on treatment outcomes or chemotherapy-related toxicities. Fasting showed a consistent trend toward decreased insulin and IGF-1 levels and increased erythrocyte levels. Three studies reported no significant differences in body weight or BMI. No specific effect sizes, confidence intervals, or p-values were provided in the abstract.
Why it matters
Despite strong preclinical interest in fasting-mimicking diets during systemic cancer treatment, current clinical evidence is insufficient to show that intermittent fasting enhances treatment efficacy or mitigates chemotherapy toxicity.
Limits
The total sample size across all nine studies was small (354 patients) and heavily skewed toward breast cancer, limiting generalizability to other malignancies and targeted treatment regimens. The abstract lacks specific quantitative data, statistical metrics, and details regarding fasting protocols.
Cited by
- partial Combining fasting with chemotherapy improves chemotherapy effectiveness and accelerates patient recovery.