Fasting for religious purposes dates back thousands of years as evidenced by references to fasting in ancient writings. Fasting for weight loss may not date back nearly as far, but the concept of fasting for weight loss is not new. In recent years, there has been a resurgence of traditional and intermittent fasting for weight loss and health. Definitions of Fasting The definition of fasting is simple: Fasting is abstaining from all food for a period of time. For simplicity sake, I like to think of traditional fasting as not eating for 24 hours and intermittent fasting as not eating for 12 to 18 hours. Both types of fasting can work for weight loss but intermittent fasting is often easier to manage and allows you to eat normally for two meals each day. What Are Some Benefits? Fasting the right way can benefit your weight loss efforts. When you fast, your body uses glycogen for energy first and then fat stores. This can translate into losing pounds over time. Some people find that short-term fasting increases their energy levels and motivates them to exercise. An important benefit that is not often discussed is that fasting can help you break a cycle of unhealthy eating. You may find that your cravings for sweets diminish and staying away from tempting foods for a time increases your confidence level in your ability to make healthy food choices. What Are Some Downsides? Fasting for more than 24 hours can cause health problems. Your immune system does not function as well, you will feel tired, and you may have nausea, or experience joint pain. Additionally, if you are like I am, resuming eating after a lengthy fast can trigger extreme cravings and a desire to binge. And of course if that happens, you probably will not want to binge on fruits and vegetables but on unhealthy foods. Another potential downside is that lengthy fasting can slow down your metabolic rate, which reduces how quickly your body burns calories. That’s not what you want when losing weight. A fix for this is to fast for shorter intervals so your metabolism stays strong and quick. Do You Always Lose Weight? Regular fasting, whether for 24 hours at a time or following an intermittent fasting schedule, can result in weight loss provided your overall calorie intake is within weight loss levels. For example, if you require 2,000 calories a day to maintain your weight you need 14,000 calories a week. Not eating anything for a day saves 2,000 calories but if you make up for those calories by eating more the other six days, you will not lose weight. How to Make It Work If you want to try fasting, I recommend following an intermittent fasting schedule where you fast for 12 to 18 hours at a time. For me, that would mean skipping breakfast and eating my first meal around lunchtime. Then I would eat an afternoon snack and dinner at 7:00 p.m. I would stop eating after dinner and fast until lunchtime the next day. The key to using fasting as a weight loss tool is to plan your fasting times carefully, commit to not overeating as you come off the fast, and to drink plenty of water or other zero calorie drinks during your fasting time.