Anyone who has ever run cross country or track will fondly remember nights before a race where they stuffed their face full of carbs in order to “load up.” Those same people might be surprised to hear that Ancient Greek athletes, the original Olympians, never carbo-loaded. In fact, they didn’t eat at all before their races. Instead, they fasted in preparation for the Olympics and other events, citing both physical and spiritual reasons.
Fasting isn’t unique to the Greeks — it is a huge part of human history that has been practiced throughout centuries by most ancient civilizations and religions. While many are familiar with Lent in Christianity, Ramadan in Islam and Yom Kippur in Judaism, did you know the Native Americans also practiced fasting before embarking on spiritual vision quests? Or that in pre-Columbian Peru, fasting was a requirement for penance after an individual had confessed their sin?
Beyond purely religious reasoning, people have used fasting as medical treatment for centuries. In the fifth century B.C.E., many physicians, including Hippocrates, prescribed fasts to people exhibiting symptoms of certain illnesses. This treatment continued throughout history, well into the 19th century, but fell out of popularity in the 20th and 21st centuries. It was only recently, given the scientific and medical communities research into the practice, that it has become popular once more. Now more than ever, we have the tools to explain how and why fasting can be used as a tool to achieve better health, deal with disease and increase longevity.
Personally, fasting is something that I practice everyday as a means to better physical and mental health, as well as concentration and academic performance. I have practiced fasting on some level since I was 7 years old when my Ukrainian chess coach cautioned me against eating before a game. “How can the blood go to your brain when it is busy in your stomach?” she would say, before instructing me not to eat two hours prior to my matches for fear that it would ruin my concentration. I can’t prove that she was exactly right (although I did go on to win quite a few games and enjoy a mildly successful childhood chess career), but I can say that she was probably onto something. The current body of scientific literature widely supports both fasting and intermittent fasting as a way to improve cognitive performance.
So what does the literature say exactly? Well, a lot. For one thing, studies have proven that intermittent fasting (IF) boosts working memory in animals and verbal memory in adult humans. Mark Mattson, a professor of neuroscience at Johns Hopkins, offers a potential evolutionary explanation for this. For much of history, humans had to survive and function in a food-deprived state or they weren’t going to be successful in finding more food.
The human species evolved experiencing long periods between kills where we had to be able to function without the consistent supply of food that we are surrounded by today, so it’s not entirely surprising that our brains and bodies are accustomed to this.
One clinical study even went as far as to show that one week of fasting can improve people’s sleep, concentration and emotional balance, suggesting that not only can we survive without food but perhaps even thrive in its absence. The benefits don’t stop there. Fasting, both IF and alternate-day, have been linked to increased brain cell generation, a multitude of cognitive and psychological benefits, resilience to neurological conditions, and slower aging effects. This research is especially exciting as we look toward the future of disease prevention and anti-aging science.
In addition to the many cognitive benefits, fasting has been shown to improve a multitude of other bodily functions and help against disease. For example, IF can help decrease blood sugar levels to help reduce insulin resistance, decrease certain inflammatory markers (which improves overall health), and enhance heart health by improving blood pressure and triglycerides and cholesterol levels. It can also mitigate and prevent neurodegenerative disorders, boost immunity, improve gut health, delay aging, and aid in cancer prevention as well as increasing the effectiveness of chemotherapy.
Of course, not everyone should engage in this practice—specifically, children and teens under 18, pregnant women, people with diabetes or blood sugar problems, and those with a history of eating disorders. But, for the most part, this is a universally healthy practice. Valter Longo, a professor of biological sciences and gerontology at the University of Southern California, explains that “The longer you fast, the more you basically kill cells. That sounds like a bad thing, but the cells that die are unhealthy ones.” The benefits of fasting are not limited to people who are overweight, predisposed to neurodegenerative disorder, or even looking to improve their cognitive functioning—given the current science, it appears to be something that could benefit all people.
IF has slowly manifested itself into an everyday practice for me, and for the past few years, I have practiced it religiously. I only eat within an eight hour period, usually 11 a.m. to 7 p.m., which might sound difficult if you’ve never tried it before, but I promise that it doesn’t take long for your body to acclimate and make it habitual. If you’re struggling with concentration, feeling sluggish, want to avoid disease, or just generally want to live a longer life, the science says that it is worth a try—and I agree!
Featured Graphic by Liz Schwab/ Heights Editor