Can Fasting Lead to a Healthier Brain?

Many of us overindulge during the holidays, making the New Year a good opportunity to reassess our eating habits. Some of us may simply want to get back to a more healthful eating regimen. Some of us may want to go even further and start a plan to lose weight. Still others are looking for ways to improve their overall health. One way to potentially achieve all of these goals is through fasting.

Fasting has a long and rich history. Hippocrates, Plato, Socrates, and Aristotle all praised the benefits of fasting. Paracelsus, considered to the founder of modern toxicology, said, “Fasting is the greatest remedy – the physician within.” Most religions embrace fasting as part of their rituals for purification, atonement, and becoming closer to God.

Today, as more scientists study fasting and its benefits, we now have compelling evidence that it may have some powerful positive effects on health. One of the most interesting is the possible connection between fasting and brain health. The leader in this research is Mark Mattson, a scientist at the National Institute on Aging. A study he led found that fasting one or two days a week may help those living with Alzheimer’s and Parkinson’s. According to Mattson, “Fasting increases BDNF, a protein that’s crucial for learning and protection against age-related cognitive decline. When the brain goes under energy restriction, we see neural activity that’s associated with protection against degeneration from stroke and aging.” You can learn more about Mark Mattson’s research and fasting’s potential benefits for the brain in his TED talk, “Why fasting bolsters brain power.”

But fasting may help in other ways as well. Here are some other potential benefits of restricting your food intake.

You’ll strengthen your immune system

Scientists at the University of Southern California say that fasting “flips a regenerative switch” that essentially restores the immune system. According to Valter Longo, professor of gerontology and biological sciences, “It gives the OK for stem cells to go ahead and begin proliferating and rebuilding the entire system. Fasting cycles can generate, literally, a new immune system.” These findings may be particularly beneficial for those whose immune systems have been damaged by aging or chemotherapy. Tanya Dorff, assistant professor of clinical medicine at the USC Norris Comprehensive Center and Hospital, who co-authored the study says, “The results of this study suggest that fasting may mitigate some of the harmful effects of chemotherapy.”

You’ll burn fat more easily

When you stop eating, your body starts to undergo several changes. Some of these changes start happening after just 12 hours. First, insulin levels start to drop, which facilitates fat burning. Blood levels of Human Growth Hormone may start to increase, which facilitates fat burning and muscle gain. The body may also induce certain repair processes, such as removing waste material from cells.

You may be able to slow the growth of certain cancers

In addition to the USC study mentioned above, a study published in the Proceedings of the National Academy of Sciences found that fasting for two days before chemotherapy helped ease its toxic side effects. Researchers at the University of California at Berkeley found that eating every other day decreased cell proliferation rates, which helps slow the development of cancers. Most recently, a study authored by Longo and published in Science Translational Medicine found that five out of eight cancer types in mice responded to fasting alone – without chemotherapy. Longo concludes “the combination of fasting cycles plus chemotherapy was either more or much more effective than chemo alone.”

As with all health regimens, you should consult your physician before starting any kind of fast. Fasting isn’t recommended for women who are pregnant or nursing or people living with severe anemia. If your doctor thinks you would be able to fast healthfully, you might want to try it. In addition to the benefits listed above, many adherents also mention increased energy, better mental clarity, clearer skin and an easing of the symptoms of allergies and digestive disorders of all kinds.

This article is not intended to replace the advice of your healthcare provider. Speak to your doctor and/or a registered dietitian if you have questions about your nutritional needs.