Fasting May Fight Cancer

GOT CANCER? A FASTING-MIMICKING diet may lead to positive changes in your metabolism and immune system. A new study from Milan (Italy) suggests that a severe calorie-restriction program is tolerable and could lead to a new avenue of scientific exploration.

Do I think that the research is good enough to have our patients adopt the practice of a fasting-mimicking diet? No, the study does not conclude that such an approach to nutrition has antitumor effects. Let’s look at the study’s merits.

The study authors begin with this observation: In mice with cancer, cyclic fasting or fasting-mimicking diets (FMDs) enhance the activity of anti-cancer treatments by changing systemic metabolism and boosting anti-cancer immunity.

But what about humans? Can a similar dietary approach yield similar effects? To find out, researchers examined 101 patients undergoing treatment for either breast cancer or melanoma. They asked the study participants to do this:

Consume 1800 kilocalories in five days (more specifically, 600 on the first day and up to 300 kilocalories for the remaining four days). The subjects repeated the cycle every three to four weeks. The patients had no diet restrictions in-between cycles, but the investigators recommended a healthy diet and lifestyle.

Here are the results of an interim analysis of the ongoing DIgesT trial, testing a 5-day fasting-mimicking cycle seven to ten days before surgery.

First, dietary interventions (such as fasting) are often challenging for patients to follow. Not for this study: 92 percent complied with the diet approach.

The patients successfully modified both body and within-tumor metabolism and immune response with compliance high.

The average blood sugar concentrations dropped by 19 percent, and insulin levels dropped by 51 percent. Serum insulin-like growth factor-1 levels went down by 30 percent. These changes held over several dietary cycles.

I was concerned about body weight, but the weight loss appeared reversible during the healthy-eating periods between fasting cycles.

That’s a brief overview of this very recent study. It is only in abstract form, but I wanted to share it with you now. I love that the fasting-mimicking diet had a broad and favorable effect on immune system function. The diet approach led to many anti-cancer programs in the cancer cells.

I have recently been thinking more about out-of-the-box approaches for my patients at high risk for cancer-related recurrence or death. I am especially interested in approaches that modulate insulin-like growth factor-1 (IGF-1).

In summary, the new study reveals that a fasting-mimicking diet is associated with a significant rise in tumor-infiltrating CD8-positive T cells. This diet leads to an anti-cancer immune microenvironment at cancer cell and systemic levels.

Let’s close with the words of research team member Licia Rivoltini, MD, head of the immunotherapy of human tumors unit at the National Cancer Institute in Milan:

“Severe calorie restriction generated a metabolic shock that activated several populations of immune cells that could boost the antitumor activity of standard antineoplastic treatments.”

I look forward to seeing results from new clinical research, including the BREAKFAST trial. This experiment is the next step in understanding the anti-cancer effects caused by calorie restriction.

Oh, I cannot resist this shot of me in fabulous Milan:

Thank you for joining me today. I hope you have a joy-filled next year.