Life-saving cancer-fighting chemotherapy works better with fewer side-effects in patients who combine treatment with fasting, medical scientists believe.
But, in analyzing pilot studies, they caution larger-scale research is vital to determine just how fasting helps combat cancer and how many patients can be helped.
“Fasting certainly works for some cancer patients — but not for all,” says Dr. Veronique Chachay, a prominent medical science researcher at Australia’s Brisbane-based Queensland University.
She tells Newsmax Health many scientific studies on the topic have been promising.
Among these studies is one by a team at The Netherlands’ Leiden University Medical Centre. It was led by a professor there who is one of that European nation’s leading medical researchers, Dr. Hanno Pijl.
Pijl’s team’s published its research in a in a peer-reviewed journal, BMC Cancer - with this startling conclusion: Evidence indicates “short-term fasting protects healthy cells against side-effects of chemotherapy and makes cancer cells more vulnerable to it.”
Chachay explains that cancerous cells are fueled by glucose — a type of sugar — that helps drive their energy metabolism, rapid growth, and resistance to chemotherapy.
“Under low blood-glucose conditions, cancer cells are in effect being starved, becoming more vulnerable to chemotherapy,” Chachay notes. “Over the past two decades, research in animals has shown restricting calories — with alternating periods of fasting and feeding — promotes protection mechanisms for healthy cells while increasing white blood cells that kill cancer cells, she continues.
“Further animal studies and early trials in humans confirmed short-term fasting prior to, and after, chemotherapy treatment reduced side-effects. It also protected healthy cells from the toxicity of the (chemotherapy) drug while killing cancerous ones.
Chachay says cancerous cells’ propensity to “thrive on glucose” was first demonstrated in the 1950s by a German physiologist named Dr. Otto Warburg.
“He also showed they (cancerous cells) were unable to use fatty acids efficiently for energy or at all,” Chachay notes.
“This idea of cancer being a disease reliant on rapid glucose metabolism has reemerged recently.”
In the Dutch study, short-term fasting was shown to be safe and well-tolerated.
Breast cancer patients received their normal chemotherapy drugs after 24 hours’ fasting during which they were allowed only water, tea or coffee.
“Patients who fasted did considerably better than those in a control group who didn’t fast,” says Chachay
No limits were placed on the amount of water, hot tea or coffee (without cream or sugar) patients could consume.
Chachay notes another animal study suggests restrict diets may help combat neuroblastoma — a common childhood where cancer cells congregate in nerve tissue of adrenal glands, chest, neck, or spinal cord. Neuroblastoma is ranked the third most common childhood cancer after leukemia and cancer of the central nervous system.
Chemotherapy generally involves breaks between courses of cancer-fighting medication. Patients in the Dutch study had 24-hour fasts before and after these.
The Leiden researchers, who confined themselves to breast cancer, noticed long-term fasting reduces “spontaneous cancer incidence and delays progression of tumors in animal tests.”
But, they added: “Chronic calorie restriction is not practical for clinical use since it causes unacceptable weight loss in cancer patients. However, brief periods of fasting may be feasible in patients and . . . were shown to slow cancer growth at least as effectively as chronic calorie restriction without compromising body weight.”
According to Chachay, other studies have shown short-term fasting makes chemotherapy more effective and lessens side-effects in some, but not all, other types of cancer. Among these are brain cancers.
She adds that further research is needed “involving more people and a greater variety of cancers. However, there’s already strong evidence that short-term fasting helps chemotherapy do its job and is also very effective in reducing side effects.”
As Chachay points out, side effects are sometimes so severe that patients abandon potentially lifesaving treatment.
“The aim of ongoing research is two-fold: improving the effectiveness of chemotherapy and reducing the level of side effects,” she says. “The outlook is very promising.”
