Why Timing Matters—for Eating, Sleeping, Exercise—and Cancer Therapies
August 28, 2019
We are designed to go to sleep when the sun sets, wake when the sun rises, and eat a big breakfast, moderate lunch and small dinner.
Most cancer diets focus on what you eat. The question of when you eat is rarely mentioned. But it may turn out to be critical to your health. A new book by Satchin Panda, a scientist at the Salk Institute in La Jolla, California, discusses this: The Circadian Code.
I’ve read The Circadian Code carefully. Dr. Panda’s book is not just about when we eat. It’s about when we sleep, when we exercise, and much more. It’s basically about bringing us back to the natural rhythms of life. It’s changing my thinking and increasingly changing the way I live.
Basically, we are designed to go to sleep when the sun sets, wake when the sun rises, and eat a big breakfast, moderate lunch and small dinner. We tend to do best if we fast for over 12 hours a day—that’s the gist of it.
Here are a few of the insights about cancer from the book:
- In 2007 The World Health Organization’s International Agency for Research on Cancer declared shift work that involved circadian disruption to be a “probable” carcinogen. Additional research involving large longitudinal studies has extended the probable link to colorectal cancer, ovarian cancer and breast cancer [p.213].
Time-restricted eating is known to reduce chronic inflammation—which is a recipe for cancer.
- A large retrospective study on women and breast cancer risk found that women who maintained a regular eating schedule and an 11-hour time-restricted eating (TRE) period every day are significantly protected from breast cancer. Since TRE is known to reduce chronic inflammation—which is a recipe for cancer—it makes sense that TRE for 11 hours reduces breast cancer risk. This is a very important finding as there are very few studies linking nutrition to cancer risk that have been validated with independent controlled human studies [p.216].
- It has been known for more than 30 years that the timing of chemotherapy matters. In one study that followed women with advanced ovarian cancers, patients were treated with two different drugs, doxorubicin and cisplatin, but at different times—a standard practice for ovarian cancer patients at that time. The women who took doxorubicin in the morning and cisplatin in the evening had less severe side effects, while the women who took the drugs on the opposite schedule had more severe side effects. Since then, many studies with other types of cancers and different cancer drugs have shown the same conclusion—timing of cancer drugs can make the therapy less or more effective [p. 216-7].
- There are similar results with the timing of surgery and radiation therapy [p.217]. It beggars the imagination why scientific findings of the timing of chemotherapy, surgery and radiation has not become a priority in clinical research and practice. The importance of circadian rhythms also applies to the metabolic syndrome—obesity, diabetes and heart disease [p. 190].
The timing of chemotherapy matters.
Chronomodulation of cancer therapies has been pioneered in the US by BCCT advisor and integrative oncologist Keith Block, MD, at the Block Cancer Center in Evanston, Illinois. You can read a summary of Dr. Bock’s work on his Chronomodulation webpage.
I think paying attention to circadian rhythms in our lives will turn out to be just as important as eating well, moving more, managing stress and the other principles of healthy living.
Dr. Panda offers many specific suggestions about when to eat, exercise, and sleep. He recommends careful attention to reducing blue light from television, cell phones and computers, and simple technologies that make that possible. He recommends old-fashioned incandescent bulbs over the energy-saving LED bulbs [p. 181].
Personally, I think paying attention to circadian rhythms in our lives will turn out to be just as important as eating well, moving more, managing stress and the other principles of healthy living we explore in BCCT. A New York Times science reporter’s review article, When We Eat, or Don’t Eat, May Be Critical for Health, lends credence to the seriousness of Dr. Panda’s findings. I predict that some day soon health conscious people will pay a great deal more attention to our circadian code. It will be about time.