Modern lifestyle permits unlimited availability to high caloric foods and sedentary habits making us susceptible to obesity and various other chronic diseases. Hunger is a learned response triggered by social, cognitive and environmental cues. This leads to overeating simply by stimulating our sense of vision, touch and smell. Overeating denies our digestive system of well-deserved breaks from doing its job of breaking down food and eliminating wastes, which can easily be accomplished through short periods of fasting.
I would like to shed some light on the concept of intermittent fasting (IF). Research suggests that we spend roughly 20 hours in the “fed state” – constantly eating, storing food and never giving it a chance to burn off. The “fasted state” begins after 8-12 hours of having a meal. 12-24 hours of fasting typically results in 20% or greater decrease in serum glucose, which allows the energy source to be switched to fats.
Intermittent fasting has become quite a useful tool for weight loss. There are endless variations to IF: alternate day fasting, modified fasting regimens and time restricted fasting. Personally, my experience lies with the time restricted fasting, so I will focus on this method. It involves daily fasting intervals ranging from 14-20 hours (8 hours of digesting + 6/8 of cleansing) and feeding periods ranging from 6-10 hours. Not a day goes by without consumption of food. This form of fasting allows people to maintain caloric restriction (the only proven method of weight loss) with better compliance than constant caloric restriction. IF may be an easier long-term method to weight loss, as it involves feeling sharp hunger pangs occasionally vs. mild hunger all the time! It allows you to stress less over the foods you eat. Now, that is not to say that it is okay to splurge and reward yourself with extra large helpings or extra deserts during feeding periods, because it is NOT! Fasting simply allows for breaks to your normal routine and allows for your digestive system to rest. Many people actually report improved energy, better sleep and overall feeling of well-being with IF.
Two Popular Keto Myths:
Myth 1: “Fasting causes metabolism to slow down”
- In actuality, being in the fasted state for short periods of time does not decrease your metabolism. This is not the same as severe caloric restriction over a long period of time, which can cause BMR to drop due to the body trying to conserve energy. In fact, studies have shown that fasting for as long as 72 hours does not affect metabolism. Increasing muscle mass through resistance training can increase metabolism. Thus, a combination of intermittent fasting and exercise will increase BMR.
Myth 2: “Fasting can cause loss of muscle mass”
- Yes, long-term caloric restriction on its own can cause you to lose muscle mass, as seen in hospital patients. However, the combination of caloric restriction with resistance exercises can preserve muscle mass. As long as you are using your muscles they will not waste away with short bouts of fasting. Resistance training is the key to maintaining muscle mass, diet plays a minimal role.
Here are benefits that can arise with short term fasting:
- Decreases body fat and body weight
- Decreases insulin levels and increases insulin sensitivity
- Increases human growth hormone (hGH)
- Decreases LDL cholesterol
- Improves gut health
- Improves liver detoxification
Intermittent fasting reduces the burden of our digestive system giving it time to heal and detoxify. It also allows fat to be used as the primary source of energy. Unlike conventional weight loss regimens, it doesn’t change what you eat (don't over-indulge), simply when you eat. I would encourage you to view intermittent fasting as a lifestyle, not a short-term diet. The biggest issue with intermittent fasting is the hunger sensation you feel in that last 2-3 hour stretch. I can tell you with personal experience, that it becomes easier to manage and you get used to the feeling of an empty stomach. Hunger sensations do go away as long as you are staying busy. Lastly, be sure not to confuse thirst for hunger. Keep drinking water and stay hydrated!
Written by: Dr. Saira Kassam | 2017