Fasting weakens cancer in mice

[aelephant]

http://www.sciencedaily.com/releases/2012/02/120208152254.htm

Fasting weakens cancer in mice

Man may not live by bread alone, but cancer in animals appears less resilient, according to a study that found chemotherapy drugs work better when combined with cycles of short, severe fasting.

Even fasting on its own effectively treated a majority of cancers tested in animals, including cancers from human cells.

The study in Science Translational Medicine, part of the Science family of journals, found that five out of eight cancer types in mice responded to fasting alone: Just as with chemotherapy, fasting slowed the growth and spread of tumors.

And without exception, "the combination of fasting cycles plus chemotherapy was either more or much more effective than chemo alone," said senior author Valter Longo, professor of gerontology and biological sciences at the University of Southern California.

For example, multiple cycles of fasting combined with chemotherapy cured 20 percent of mice with a highly aggressive type of children's cancer that had spread throughout the organism and 40 percent of mice with a more limited spread of the same cancer.

No mice survived in either case if treated only with chemotherapy. ...

In a case report study with self-reported data published in the journal Aging in 2010, 10 cancer patients who tried fasting cycles perceived fewer side effects from chemotherapy. ...

In mice, the study found that fasting cycles without chemotherapy could slow the growth of breast cancer, melanoma, glioma and human neuroblastoma. In several cases, the fasting cycles were as effective as chemotherapy.

Fasting also extended survival in mice bearing a human ovarian cancer. In the case of melanoma, the cancer cells became resistant to fasting alone after a single round, but the single cycle of fasting was as effective as chemotherapy in reducing the spread of cancer to other organs.

For all cancers tested, fasting combined with chemotherapy improved survival, slowed tumor growth and/or limited the spread of tumors. ...

While normal cells deprived of nutrients enter a dormant state similar to hibernation, the researchers saw that the cancer cells tried to make new proteins and took other steps to keep growing and dividing.

The result, Longo said, was a "cascade of events" that led to the creation of damaging free radical molecules, which broke down the cancer cells' own DNA and caused their destruction.

"The cell is, in fact, committing cellular suicide. What we're seeing is that the cancer cell tries to compensate for the lack of all these things missing in the blood after fasting. It may be trying to replace them, but it can't," Longo said.

[Todd Becker]

Thanks for the excellent reference to the Science article, aelephant. The connection between sugar and cancer goes back to Otto Warburg's discovery in 1931 that cancer thrives on glucose:

http://www.drheise.com/cancersugar.htm

Ketogenic, high fat diets have also been found to be very useful in controlling or reversing cancer:

http://www.time.com/time/health/article/0,8599,1662484,00.html

Thus, it makes sense that intermittent fasting could be helpful in controlling cancer.  What is most interesting to me in the article you quote is the element of cyclic fasting.  Perhaps the alternation between feeding and fasting works to prevent cancer cells from adapting to a state that allows them to grow and metastasize freely.