recycles damaged organelles and proteins , which in part contribute to the suppression of tumorigenesis . Inflammation and oxidative stress are both reduced in the fasting state , reductions which play a crucial role in slowing cancer development and progression . During the fasting state ketones are produced from the liver from fat-derived glycerol , fatty acids and amino acids . These adequately fuel the brain and may slow tumour progress [ 6,7 ].
Potential clinical applications of fasting diets on chemotherapy treatment outcomes
Negotiations with the clinical team are advisable to establish the suitability of each patient for the fasting treatment chosen , and the suitability of that treatment for the patient and the chemotherapy regime . The patient would need to be invested and involved in the decision-making process .
Potential areas for further research
Although the theory is promising further research is required in human studies . A recent review suggests there are currently insufficiently powered studies to detect significant effects and consistent endpoints from which to conclude .
Conclusion
While data remains scarce , both shortterm fasting and fasting-mimicking diets exhibit potential as emerging nutritional therapies during chemotherapy , particularly for cancers with a low risk of malnutrition and cachexia . However , there are notable obstacles that prevent the widespread adoption of these diets as nutrition therapy . There is a paucity of efficacy data , challenges in patient adherence , and a high dropout rate . However , the available research suggests that in well-nourished patients , fasting has the potential to reduce toxicity and decrease chemotherapy-induced DNA damage , improve QoL , reduce fatigue , and moderate inflammation , all of which are related to prognosis and survival . There is a necessity to better understand the effects of different fasting approaches
Categories of fasting diets
FASTING 48-72 HOURS
Short-term fasting during the chemotherapy process over a 48-72-hour timeframe has been proposed as more effective in reducing chemotherapy toxicity than shorter durations [ 5 ]. Human evidence is not sufficient to draw definitive conclusions . Timelines of the most promising results in the small trial were 48 hours before treatment or 24 hours before and after treatment , or 72 hours surrounding treatment ( i . e ., 48 hours before and 24 hours following chemotherapy ) [ 5,7 ].
Outcomes : Effective in reducing toxicity of chemotherapy ; safe ; reduced changes in blood work ; adherence ; and improved QoL .
FASTING MIMICKING DIETS A kilojoule restriction of 20-40 % FMD or CR has been the subject of more studies than fasting in solid tumours . This is attributed to the fact that a common therapeutic goal in cancer treatment is the avoidance of weight loss and that it is considered more tolerable than fasting . FMDs have shown potential benefits in reducing chemotherapy-related side effects and improving the QoL in cancer patients receiving chemotherapy . A human controlled cross-over pilot study in gynaecologic patients of a modified short-term fasting of 96 hours with caloric restriction of 25 % of each patient ’ s daily requirement indicated that this increased tolerance to chemotherapy [ 2,8 ]. Another study suggested benefits were provided by a very low calorie low protein diet for 1 week per month .
Outcomes : improved weight maintenance , improved patient tolerance and improved QoL .
TIME-RESTRICTED FEEDING TRF or intermittent fasting is episodic periods of low or no kilojoule intake . The approach encompasses a plethora of programs where food intake is restricted to a short eating window . This may include fasting every other day , a 16-hour fast and an 8 hour eating window twice a week , or a 24-hour fast , or fasting on one or more consecutive days a week . The available data indicates that periodic fasting for 24 hours , a type of intermittent fasting , may enhance the efficacy of chemotherapy , reduce treatment-associated side effects , and mitigate cancer-promoting factors such as insulin . Concurrently , it may alleviate treatment-induced declines in QoL and daily living [ 8,9 ].
The timing of short-term fasting for efficacy in outcome-related benefits is not prescriptive at the time of this overview .
Outcomes : safe for well-nourished patients , reduced chemotherapy toxicity and improvements in treatment response .
84 | vol30 | no2 | JATMS