Intermittent Fasting: Scientific Evidence for Benefits of Fasting and How to do it RIGHT, PART 1
“Entire religions have evolved from one man’s fast, empires toppled, wars halted. For examples we need look no further than Jesus, Muhammad, the Buddha, Gandhi.” - Annemarie Colbin
History
There is evidence of fasting going back to the earliest of recorded history. Some of the greatest thinkers the world has ever known have been known to use fasting for health and healing. Hippocrates, Plato, Socrates, Aristotle, and Galen all acclaimed the doles of fasting. One of the three fathers of western medicine, Paracelsus, was quoted as saying, “Fasting is the greatest remedy-the physician within.” Many fasting rituals were used by religious and spiritual groups as part of ceremonies and rites, often during spring and fall equinoxes. To this day almost every major religion practices fasting for various reasons. Christianity, Judaism, Gnosticism, Islam, Buddhism, Hinduism, and South and North American Indians all make use of fasting in some form. Whether for cleansing, spiritual vision, reparation, mourning or sacrifice, as well as breaking the habits of gluttony. Yogic practices employing fasting rituals date back thousands of years. Paramahansa Yogananda said, “Fasting is a natural method of healing.” Still today the ancient practice of eastern medicine called Ayurveda includes fasting as a remedy.
Science
There have been multiple scientific studies done to confirm the physiological benefits of intermittent fasting. In a study completed WAY back in 1945 by Anton J Carlson and Frederick Hoelzel in the University of Chicago’s Department of Physiology, they looked at how Intermittent Fasting affected rats. They concluded that the apparent life span of rats tested was increased with statistical significance from intermittent fasting. Rats experienced the optimum amount of fasting while using the 1 day in 3 protocol. That is fasting for one out of every three days, this increased lifespan in males by 20%, and females by 15%! Extrapolation of this data to humans can be legitimately argued, but assuming it can be, based on the average lifespan in the US being 78.94 years, that’s 15.8 additional years for males and 11.8 for females!
A more recent study done on humans published in 2013 in the journal Metabolism by Klempel MC, Kroeger CM, and Varady KA out of the University of Illinois Department of Kinesiology and Nutrition shows that body weight was reduced, fat mass decreased, waist circumference decreased, and LDL cholesterol and triacylglycerol concentrations were reduced! These finding were all very statistically significant as well with no P levels higher than .001.
Varady KA also completed a Meta-analysis of Alternate-day fasting and chronic disease prevention in both humans and animals. He concluded: animal studies have found lower diabetes incidence, lower fasting glucose and insulin concentrations, lower total cholesterol and triacylglycerol concentrations, lower heart rate, improved cardiac response to cardiac infarction, and lower blood pressure. Human evidence suggests higher HDL cholesterol concentration and lower triacylglycerol concentrations but no effect on blood pressure. There has been no human evidence to date on fasting and cancer risks but animal studies found decreases in lymphoma incidence, longer survival after tumor inoculation, and lower rates of proliferation of several cell types.
Studies showing that fasting mildly stresses cells in the body, including neurons, in turn making them more resilient: Mark P. Mattson working out of the Laboratory of Neurosciences at the National Institute on Aging Intramural Research Program states that “the emerging evidence that DER and specific chemical components of the diet can elicit hormetic responses in various types of cells opens new avenues for both basic and applied research in the fields of nutrition, ageing and disease. Frequency of exposure to the diets should be evaluated as intermittent exposures to DER (dietary energy restriction) and phytochemicals may prove superior to more frequent exposures.”
Another study from the National Institute on Aging, Laboratory of Neurosciences from R. Michael Anson et. al. concluded that, “Intermittent Fasting resulted in beneficial effects that met or exceeded those of caloric restriction including reduced serum glucose and insulin levels and increased resistance of neurons in the brain to excitotoxic stress. IF therefore has beneficial effects on glucose regulation and neuronal resistance to injury in these mice that are independent of caloric intake.”
Summary
Considering how widely utilized fasting has been historically it is unbelievable that with all of the emerging scientific data that more people are not establishing some sort of Intermittent Fasting protocol. As stated above, there are several physiological benefits to incorporating IF into your current diet plan. Even without scientific data, famous philosophers and thinkers of the past instinctively knew that fasting was a good thing for the human body. They hailed the positive effects of fasting on health and well being.
Part 2 of this Intermittent Fasting series will focus on implementing IF into your current diet plan, regardless of what schedule or type of diet you are adhering to and some common problems you can proactively avoid.
I hope to have that out within the next couple days as it takes time to find sources and read/comprehend scientific literature. Hope you enjoyed part 1, if so please resteem this article and comment, upvote, and follow my blog!
Your friend in Health, Ryan.
Very interesting article. From what I understand fasting or calorific restriction can trigger the expression of SIRT 1, an enzyme which is thought to be a metabolic master switch and can potentially extend life span. Dr. David Sinclair, an Australian scientific researcher, has discovered that SIRT 1 can also be expressed by resveratrol. NAD+ seems to activate SIRT1-7 also with potentially life lengthening results.
Thank you for the thoughtful comment @michaelmay . That is very interesting and yet another benefit of fasting! In part two of this series I am going to tie in grhelin and CCK, two hormones involved in hunger signals in the brain, ultimately linking into ketogenic diet and how intermittent fasting can help trigger a deeper ketosis.
Great post.
I actually try to fast at least once a month for 24-36hours. I believe our body is a biological machine designed to handle extremes - feast and famine. And we are simply not made to constantly take in calories the way we do in our modern life.
I always feel amazing after the fast and have a heightened mental clarity, more energy, and very keen sense of smell for anything delicious. :D
Thank you @somethingsubtle ! I am currently on a 16 hour/day fasting protocol. That leaves me with 8 hours/day to eat. Usually I fast 10pm-2pm. I've never felt better or performed better in my entire life! And I'm so glad you said that about having enhanced senses for food! Every. Single. Day. When I break my fast my meal tastes SO GOOD! Granted I spoil myself with great tasting, organic food, but every bite I take tingles my taste buds. Amazing feeling.