Fasting: How to do a 24-hour fast

Glass of water on empty plate

During fasting, eat no food, not even health food. This is about behavior change.
Photo: Jean Fortunet/Wikimedia/CC-BY-1.0

Make sure you have read the post: Fasting: What it is, Why try it

I recommend trying a 24-hour mini-fast (any fast of 24 hours or less). You should do this no more than once a week.

(Most of the instructions below would also apply to a shorter fast of four or eight hours. But don’t confuse such a short, planned fast with impulsively skipping meals. Almost anyone can safely fast for 24 hours.)

With a 24-hour mini-fast, you never go a whole day without eating. Fasting begins as soon as you finish a meal. When you put your fork down, look at the clock. In 24 hours it will be time to eat again. Here are two examples, starting after a breakfast and a dinner. Plan a time that works well for you, your family, your obligations and your social life. Choose one of the following:

  • Start after breakfast – On Friday morning, finish a regular breakfast at 7:30 am, which is when your fast begins. The fast ends on Saturday morning at 7:30 am, when you eat a regular breakfast. Or:
  • Start after dinner – On Thursday evening, finish a regular dinner at 7:30 pm, which is when your fast begins. The fast ends on Friday evening at 7:30 pm, when you eat a regular dinner.

Foods allowed during fasting
24-hour fast Dr. TheresaNo food or eating is allowed during fasting. It’s about behavior change. That means no low-calorie or no-calorie food. In this case, a carrot is the same as carrot cake.

If you decide you must eat something, end the fast and try again next week or when you are ready. Training always includes failures. F. Scott Fitzgerald wisely said, “Never confuse a single defeat with a final defeat.” Failure doesn’t make YOU a failure. Developing good habits takes time and practice.

Liquids allowed during fasting
RECOMMENDED: These will allow your body to stay in the fasted (fat-burning) state.

  • Water: still or sparking, but no flavoring.
  • Water with lemon or lime
  • Black coffee
  • Tea with no sugar or sweetener and no milk
  • Tea with lemon

ALLOWED with reservations: The drinks below put your body into fed state, but for a short time. (Try to stick to the list above if you want to burn fat during your fast. Remember you don’t LOSE weight, you USE weight—but only in the fasted state.)

  • Tea or coffee with a small amount of milk or sugar
  • Diet drinks (even those with no calories change the hormone balance in body)
  • Clear broth

NOT ALLOWED: Anything not on the other two lists: milk, juice, sports drinks, cappuccino, beer, wine or any other drink. (Similarly, no artificially sweeteners like Equal, Splenda, Stevia and Agave. They trick your brain.) These put your body into the fed state; you might as well eat. If you decide to have one of these drinks you should consider your fast over for this week. Try again next week or when you are ready.

NOT NEEDED: You do not need any special drinks, supplements, cleanses or detoxifiers. Keep it simple.

Breaking the fast
At the end of the fast, remember that you didn’t do anything special. You just delayed eating for a little while. No reward is justified. There is no reason to gorge. Enjoy a regular sized meal. Remind your brain that you kept your word and broke the fast as scheduled. Next time the brain will trust you a little more, and it will be easier.

Tips for success
1. Plan ahead to remove temptation
Use the thinking part of your brain to plan your environment for success. Act ahead of time to avoid temptation so you do not have to battle it during the fast. Remove tempting snack foods from the house. Maybe skip a shopping trip before your scheduled fast. Plan to fast at a time that is most convenient.

2. Set your intentions
Some people sabotage their fasts by starting with the wrong intention. If you think fasting is about “not-eating” or “deprivation,” you will struggle needlessly. Remind your brain that fasting isn’t about not eating, it’s about eating at a predefined time in the future. Reassure your brain that you will eat again as scheduled.

3. Handle hunger pangs
Prepare to feel hunger pangs. Have a strategy. One response is to embrace hunger as a sign that your body is releasing stored fat and using it for energy. When you feel hungry imagine that you are actually opening your saddlebags or fanny pack on your belly and depleting them! You are USING fat. Another response is to treat hunger like a bratty child demanding a treat. You are a grownup, a mature master of your emotions who ignores the brat., Theresa Nesbitt and her publications provide general information on health and wellness. This general information is not a substitute for health advice and medical care from physicians who know you. Please talk to them before making significant changes in your lifestyle. Complete Terms of Use and Disclaimers