A Complete Guide to Intermittent Fasting

Intermittent Fasting Guide
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Intermittent fasting, or IF, is more than the latest weight loss trend, it’s a path to greater health. Practiced throughout history, the benefits of IF extend to the heart, the brain and the body’s metabolic system. 

This simple guide to fasting explains the history of intermittent fasting, its benefits and how to choose the protocol that’s best for you. 

Intermittent Fasting Defined

What does fasting mean? Fasting is abstaining from food. While fasting, it’s OK to drink water, coffee and tea, as long as there are no added sugars that would cause the body to metabolically leave the fasted state. Intermittent fasting means abstaining from food for a specified period of time, interspersed with periods of regular eating. 

Typical intermittent fasting protocols include the following: 

Beginner Guide to Intermittent Fasting

16:8. You’ll fast for 16 hours, most likely overnight, followed by eight hours of eating. 

5:2. You’ll eat normally five days per week, interspersed with two non-consecutive days of fasting. 

Alternate Day Fasting. You’ll eat normally on day one, eat no more than 500 calories on day two, then repeat. 

Eat Stop Eat. You’ll eat normally through dinner on day one, abstain from food until dinner on day two, then repeat.

There’s no one way to do intermittent fasting, and there’s a fasting plan to fit everyone’s lifestyle.

The History of Intermittent Fasting

Intermittent fasting is as old as humankind, whether done intentionally or not. It’s easy to imagine our early ancestors going without food from sundown until late the following day, as they spent their morning hours hunting and gathering for the afternoon’s meal. 

References to fasting as a means of healing date back to ancient Greece. Hippocrates, the father of modern medicine, recommended the practice, as did Plutarch, Plato and Aristotle. 

Fasting has long been part of spiritual practice within each of the world’s authentic religions, not only for its ability to heal the body but for its potential to bring clarity to the mind. 

Benefits of Intermittent Fasting

Intermittent fasting has several benefits, many of which have been observed and replicated through randomized clinical trials in both animals and humans. While most turn to fasting for weight loss, anyone can benefit from intermittent fasting.

Weight Loss. While individual results vary, a comprehensive review of 40 studies on intermittent fasting found that participants in a fasting protocol may lose between 7 to 11 pounds over 10 weeks. According to most physicians, this gradual weight loss, at under 2 pounds per week, is safe and more likely to last in the long term. 

Heart Health. Heart disease and issues related to heart health contribute more than any other factor to death in the United States. Metabolic syndrome, the collection of risk factors that leads to heart disease, can be improved by intermittent fasting. 

Insulin Sensitivity. Insulin resistance is a pandemic in much of the world, as type 2 diabetes, in particular, becomes increasingly common. 

Intermittent fasting helps reduce sugars in the bloodstream by reducing the number of sugars consumed, promoting weight loss, and reducing body fat. 

Brain Health. Intermittent fasting improves brain health by reducing systemic inflammation, stabilizing your blood sugar and removing free radicals. In particular, it promotes the production of an important brain protein, BDNF, and encourages autophagy, a natural process in which the body breaks down and eliminates old or damaged cells.  

The Complete Intermittent Fasting Guide

It’s our hope that this intermittent fasting guide helps motivate you on your journey to better health. Knowledge is power. The more you know about intermittent fasting, the more likely you’ll be to stick with your fasting plan and realize positive results. The following chapters of our intermittent fasting guide will uncover in more detail how to fast effectively to gain all the mentioned benefits.

Chapter List

Chapter 1. Benefits of Intermittent Fasting

Chapter 2. How to Do Intermittent Fasting

Chapter 3. Nutrition Guide

Chapter 4. What to Drink During Intermittent Fasting

Chapter 5. Intermittent Fasting Plans

Author's bio


Sara-Mai Conway

Sara-Mai is a writer who specializes in physical and mental health, nutrition, and fitness. She has 20 years of professional experience in the health and wellness industry and is a certified yoga instructor.