The health and fitness industry has been all abuzz in recent years about intermittent fasting (IF) or time restricted eating as if it is something new. Fasting simply means going for a period of time without eating. Many of the religions of the world have been using periods of fasting as a spiritual practice for centuries. There really is nothing new under the sun. All of us fast every day while we are sleeping. The only thing that makes today’s concept of fasting different is that research has now proven that extended periods of fasting can have a number of health benefits.
For the purpose of this blog entry, I will be giving you a basic introduction to the concept of time restricted eating of 24 hours or less without food based on the research as well as my personal experience. I will not be discussing the more extended fasting regimens that might go on for several days or even weeks. These extended fasts are best done under the supervision of a medical professional.
HOW INTERMITTENT FASTING PROMOTES GOOD HEALTH
Our bodies are always in either one state or the other, we are either in the fasted state or the fed state. During the fasted state our bodies are resting and repairing themselves. One of the most important aspects of the fasted state is the reduction in the hormone insulin which you will recall from previous blogs entries is known as the fat storage hormone. Any time you can lower your insulin levels for prolonged periods of time you are less likely to increase your body fat. In addition, fasting can reverse insulin resistance which has been linked to the development of obesity and Type 2 Diabetes. When the body no longer has food for fuel it turns to the glycogen stored in the liver. Once the glycogen stores are depleted, the body begins to burn its own fat. Hence, intermittent fasting has became a valuable tool for many of us both for weight loss and weight maintenance and for our attempts to achieve good overall health.
In addition to weight loss and the prevention of obesity and diabetes, intermittent fasting has been shown to have numerous other health benefits including improved mental focus, better digestion, decreased overall inflammation, better heart health and an improved immune system. Intermittent fasting also can play a major role in management of the symptoms of the perimenopause and menopause in women. As an aging woman, I have experienced those benefits myself and have begun recommending IF to patients.
TIME RESTRICTED EATING PLANS
1. Short fasts are fasts between 12 and 15 hours in a 24 hour period. For example, a 12:12 fast means that you fast for 12 hours each day. All of your meals are eaten within a 12 hour “window.” This usually means that you simply stop eating 3-4 hours before bedtime and have your first meal of the day 12 hours after whatever time you had dinner. If you are a nighttime snacker, this simple change in your eating habits will be a challenge at first but it is a great way to decrease your overall food intake. Close your kitchen by 8pm, stop eating for the night and you are well on your way to a fasting lifestyle. These short fasts are thought to be the easiest of the fasting approaches because most of the fasting is done while you are sleeping.
2. The most popular IF plan is 16:8 in which your eating window is only 8 hours per day. During your fasting window you are encouraged to drink water and 0 calorie beverages like black coffee and tea. With this plan you can usually get in two meals during the eating window. Some experts believe that unless you fast at least 16 hours you may be missing out on some of the health benefits of fasting. Some choose to stretch out their fasting window to 17 to 23 hours daily. These longer daily fasts are thought to be necessary to reap benefits of autophagy wherein the body begins to clean out the old, unwanted, and unneeded cellular material, as well as fixing and recycling damaged parts. Autophagy is thought to be important for being our healthiest selves as we grow older.
3. The 23:1 mode of daily fasting is also known as known as One Meal a Day or OMAD. You get to decide which single meal you choose to have but most OMAD users fast from dinner to dinner so they can have the evening meals with family and/or friends.
4. Eat Stop Eat is a strategy that has you refrain from eating for a full 24 hours once or twice a week and to eat normally on the non fasting days.
5. The 5:2 plan, also called the modified Alternate Daily Fast method, restricts calories to 500 on 2 non consecutive days of the week with normal eating on the other days. Many argue that this is technically not a fasting regimen but I include it here for the purpose of informing you of the option.
MYTHS ABOUT INTERMITTENT FASTING
1. Fasting starves the body and will zap your energy. The truth is that even lean individuals carry hundreds of calories in their livers in the form of glycogen and in their body fat. That is why we have stored fat in the first place, to use as a food source when food is not available. No one ever starved to death going a few extra hours without food. We have been told for years that we need to eat 5 times a day to keep our blood glucoses up. That is simply not true but is certainly what the food industry would like for you to believe. In the decades that we have followed this advice we have seen the rates of obesity and diabetes skyrocket. There must be a better way!
2. You will be ravenously hungry if you fast. A lot of the eating we do is out of habit because we have trained our bodies to eat at certain times. We can also train our bodies NOT to expect to eat by easing into the fasting lifestyle gradually. Most people have what I call head hunger at the expected mealtimes the first few days of a fasting lifestyle. That why it is a good idea to start a fast after a satisfying meal followed by overnight sleep then pushing your first meal of the day an hour later each week. Drinking water and zero calorie beverages are a big help in curbing hunger and cravings in the early weeks of a fasting lifestyle. Cutting back your consumption of sugar, simple starches and processed foods will also make you more successful at fasting. The body will learn to crave whatever you regularly feed it. If you continue to eat sugary treats, you will continue to crave sugary sweets.
3. Fasting will make it difficult to concentrate. Most people report that once their bodies adjust to a fasting lifestyle they actually have better mental acuity. It is not true that humans need food to be mentally sharp. Quite the opposite is true. Think of how sleepy you get after a big meal when the blood flow to the brain is compromised by digestion. Studies have shown that there is actually increased brain activity in mammals in the fasted state.
4. You can eat whatever you want during in your eating window. This is the most dangerous myth of all! Let us not forget that this is a healthy living blog. The key to a healthy lifestyle is not just when you eat, it is also WHAT you eat as well. You cannot use fasting as an excuse to pig out on junk food regardless of what you see on social media! Unless you nourish your body with leafy greens, protein, healthy fats and fiber, fasting alone will not help you reach your wellness goals.
WHY SHOULD YOU CONSIDER FASTING
According to Dr. Jason Fung, author of the Obesity Code and the Complete Guide to Fasting, there are several reasons to consider a fasting lifestyle.
1. Fasting is simple and convenient. Even if you eat just one less meal a day that is one less meal you have to plan and prepare and take the time to eat. Think of the time you will save.
2. Fasting is free. After all the money most of us have spent on diet programs, we finally have a strategy that doesn’t cost a penny. Not only that but you will be cutting your food budget by at least one third! In a sense you are being paid to lose weight and improve your health!
3. Intermittent fasting is flexible. It can be used with the dietary eating style of your choice. Because I am pre-diabetic, I use 16:8 daily IF in combination with a low carb/healthy fats eating style. Low carb eating is a great way to get rid of cravings and hunger and makes it easier to be a consistent faster. However, IF can also work wIth other healthy eating plans like vegetarian, vegan, plant based, whole 30, paleo, keto, etc. Once you find the eating plan that works with your health needs and goals, time restricted eating is a great adjunct to make that plan even more effective.
4. Intermittent fasting is great for maintenance of weight loss. Regardless of the method you use, 80-90% of persons who lose weight will regain it within 2 years. Intermittent fasting is a lifestyle that you can use forever in order to stay at a healthy weight.
On a personal note, I originally started IF 2 years ago searching for a way to maintain the weight loss I had attained by switching to a low carb way of eating. I was determined not to do what I had done so many times before when I regained the weight. Not only was I able to maintain the weight loss, I was able to do all my morning workouts in the fasted state without feeling hungry! I have even done several half marathons in the fasted state with no need for carbs before, during or after the races. In the past few weeks I have been experimenting with stretching my fasting window to up to 23 hours a couple of days a week and I am amazed at the amount of energy I have on those days. I can also report that my gimpy left knee hardly ever talks to me any more. I think she likes this fasting lifestyle!
As always, I do not claim to have all the answers to how to become a healthier you but it is my prayer that the information you find here will help you in your journey. I encourage you to share the blog with your friends and family and to contact me in the comments if you have questions.
Yvonne Moore, MD
“Dear friend, I hope all is well with you and that you are as healthy in body as you are strong in spirit.” 3 John 1:2 (NLT)