Historically, food sources haven’t always been so readily available and humans have had to go for long periods of time without food. Eating three meals a day is actually a relatively modern concept and while it works for many, for others periods of fasting are highly beneficial.
Most religions have maintained that fasting or skipping meals is good for the soul. Think of Ramadan, a time for spiritual reflection wherein Muslims fast from dawn until sunset for twenty-nine days. In Christianity, Lent is a forty day period during which people are encouraged to give up food groups. While Lent is certainly not the same as intermittent fasting, it is similar in that the focus is on phasing meals or food groups for spiritual reflection.
Recently, Western Medicine has shown that intermittent fasting has many health benefits. Rather than being what we eat, evidence suggests that we are actually when and how we eat.
Intermittent Fasting means skipping meals or choosing your eating windows throughout the day. While intermittent fasting shortens your eating window, it isn’t necessarily about calorie restriction. Instead, intermittent fasting is a purposeful approach to consumption that yields positive results for brain function, lowers inflammatory markers and may extend life expectancy; just as you make conscious choices to skip meals, you make conscious choices to sit down and feast. (1)
In animal studies, both brain functioning and shape have changed in the groups practicing chronic intermittent fasting. The brain is very malleable and quickly responds not only to what, but also when we eat. Fasting ramps up what is called autophagy, a process by which the body rids itself of damaged molecules, including those tied to neurological diseases like Alzheimer’s and Parkinson’s, and enhances the brain’s ability to heal itself. (2, 3)
Studies have shown that mice who go through periods of intermittent fasting have higher levels of BDNF (brain derived neurotrophic factor), an important protein that enhances brain function and plasticity. As a result, intermittent fasting has proven helpful for those with traumatic brain injuries.
Other promising benefits of intermittent fasting are improving insulin sensitivity and glucose regulation, without the need to restrict calories. (4) Healthy insulin function is key to preventing diabetes.
At Parsley Health we recommend that members who don’t have any conditions that would make intermittent fasting unsafe, such as insulin dependent diabetes, begin by doing a 12-hour fast overnight. For example, if you eat dinner around 7pm you would then wake up in time for breakfast at 7am. This process gives the body a 12-hour window of fasting, during which the digestive system can process and assimilate food. It will also curtail late-night snacking, which is a wise choice for anyone, fasting or not.
If you find yourself getting hungry after dinner, ask yourself if you are truly hungry, or if the sensation you feel is actually thirst (hunger and thirst are often confused). Drinking water and winding down by reading or doing some light stretching at night are easy ways to prevent late-night pantry raids.
If a 12-hour fast goes well, you can try increasing the period to 16 hours. You can do this daily, or if you’re just getting started, we recommend 3 days per week.
Patients we have worked with have found a lot of success with intermittent fasting. For some just one night yields benefits like increased focus and metabolism, while others need a few weeks of 12-hour fasting windows to see results. Regardless of how long it takes, nearly all report waking up feeling physically lighter and mentally sharper. Even if you can’t do a fast every night due to work or social events, aiming to do it whenever possible is still beneficial.
After working as a Health Coach for two years at Parsley Health, Elisa has moved over to the clinical operations and content department. Elisa supports day-to-day clinical operations company-wide and is also spearheading building a robust educational resources database.
Elisa is a Certified Functional Nutrition and Lifestyle Practitioner through The Functional Alliance’s Holistic Nutrition Lab as well as a Certified Health Coach through The Institute for Integrative Nutrition. Elisa is a graduate of The Natural Gourmet Institute in NYC and earner her undergraduate degree in Secondary Education at The College of St. Rose. Elisa firmly believes that each meal is a chance to impact mental and physical health. In her spare time, Elisa is an avid basketball fan and player, enjoys spending time with friends, and is also raising two sweet kittens in her Brooklyn home.