Short-Term Fasting Improves Quality of Life During Chemotherapy
Eating only about 200 calories a day for two days before and one day after receiving chemotherapy improved quality of life and helped prevent fatigue in women diagnosed with early-stage breast cancer, according to a study.
The research, “Effects of short-term fasting on quality of life as an add-on option during chemotherapy,” was presented on Oct. 20, 2023, at the European Society for Medical Oncology (ESMO) Congress 2023.
About the study
The German study included 106 women ages 29 to 71 diagnosed with early-stage breast cancer.
Among the women:
18.2% were diagnosed with hormone receptor-negative breast cancer
81.8% were diagnosed with hormone receptor-positive breast cancer
All the women received chemotherapy:
15.4% received four cycles of Adriamycin (chemical name: doxorubicin) or Ellence (chemical name: epirubicin) every three weeks, followed by four cycles of a taxane, such as Taxol (chemical name: paclitaxel)
84.6% received four cycles of Adriamycin or Ellence every three weeks, followed by 12 cycles of a taxane
45.3% received chemotherapy before breast cancer surgery
54.7% received chemotherapy after surgery
The women were randomly split into two groups, a short-term fasting group and a plant-based diet group:
The short-term fasting group included 52 women. For 36 to 48 hours before chemotherapy and for 24 hours after chemotherapy, they ate only about 200 calories a day, in the form of vegetable juices and vegetable broths.
The plant-based diet group included 56 women. For the same time period before and after chemotherapy, they ate a plant-based diet and avoided foods made up of refined carbohydrates (bread, pasta, crackers, soda) and foods high in sugar and protein.
The researchers advised both groups to eat a more vegetable-based diet overall, but this wasn’t required.
The researchers used a standard survey called the FACT-G (Functional Assessment of Cancer Therapy-General), to assess the women’s quality of life. The survey asked about physical, social, emotional, and functional well-being.
To measure fatigue, the researchers used another standard survey called the FACIT (Functional Assessment of Chronic Illness Therapy-Fatigue).
The women filled out the surveys:
before starting chemotherapy
after each chemotherapy session
four months after chemotherapy ended
six months after chemotherapy ended
Results
At the beginning of the study, both groups had similar scores on the FACT-G survey, meaning quality of life was roughly the same among participants.
After the fourth cycle of chemotherapy, the short-term fasting group’s average score on the FACT-G survey was nine points higher than the plant-based diet group’s. This difference was statistically significant, which means that it was likely because of the difference in diet and not due to chance.
“What was even more striking was the impact fasting had on fatigue,” said presenter Daniela Koppold, MD, of Charité University Medicine in Berlin, Germany. “The short-term fasting group didn’t even develop any clinically visible fatigue. They were in a normal range [for fatigue] by cycle four [of chemotherapy], while the [plant-based diet] group developed fatigue as we would have expected.”
Dr. Koppold also noted that fasting didn’t affect the women’s weight, which was important because losing too much weight during chemotherapy can cause more side effects and interfere with the medicines’ effectiveness.
She also pointed out that women who were underweight or who had a history of an eating disorder were excluded from the study.
There were no differences in scores for anxiety and depression between the two groups, suggesting that the difference in quality of life wasn’t based on those factors.
“In summary, short-term fasting represents a promising supportive therapy during breast cancer chemotherapy to enhance quality of life,” Dr. Koppold said.
What this means for you
The results of this study are very encouraging, but there are a few things to keep in mind before you try short-term fasting before and after chemotherapy.
This study looked at an older chemotherapy regimen. The standards of care have changed and many people now receive dose-dense chemotherapy, meaning they receive chemotherapy every two weeks rather than every three weeks. So it’s unclear if short-term fasting would have the same effects on quality of life and fatigue during a different chemotherapy schedule or a regimen that uses different medicines.
All the women in this study were diagnosed with early-stage breast cancer. It’s not clear if short-term fasting would offer benefits to someone receiving chemotherapy for metastatic breast cancer.
These results come after the fourth chemotherapy session; none of the women had received a taxane yet. So it’s not clear if short-term fasting will offer the same benefits during taxane chemotherapy.
It’s also very important to talk to your doctor before trying short-term fasting before and after chemotherapy. If you have a poor appetite and are losing weight during chemotherapy treatment, short-term fasting may make you lose even more weight and feel worse.
— Last updated on November 15, 2023 at 7:09 PM