Becoming dehydrated while fasting is easy to do and many people are not aware of this. So now you are probably wondering how much water to drink while intermittent fasting. 

When you are fasting, your body is breaking down stored supplies of energy in the form of glycogen (sugar) and fat. When your body breaks down glycogen for energy, you can lose a lot of water, meaning you should drink more liquids during your fasting window.

Additionally, the food we eat naturally contains water. This means that if you are fasting for an extended period of time, you are not getting water and the benefits of water you typically get while you are eating. 

Also, read – 18/6 Intermittent Fasting: The Secret to Sustained Weight Loss 

This all being said, it is incredibly important to drink water during fasting periods. This will help ensure that you are staying hydrated and it can also help ward off hunger pains and feelings of tiredness. Try adding lemon or cucumber to your water for variety. Likewise, unsweetened herbal tea is another good alternative don’t forget about iced tea during the warmer parts of the year!

One thing to note, you want to make sure you are not drinking too much water because you may start to experience bad effects of water such as bloating and diarrhea. It is recommended that the average adult drink 8 cups of water a day but try to drink one more cup for every hour you are fasting and go from there. You can adjust and drink less or more depending on how you feel.

Keep in mind that athletes and more active individuals are going to require more water and liquids than the average person and this doesn’t change if that individual is on a fasting diet.

Asked by: Mary D.

Clinical Project Manager and Writer

With a Ph.D. in nutritional biology, Dr. Richardson is an expert in the field of nutrition, particularly intermittent fasting. Her dissertation project was an intermittent fasting study in athletes, which is where she gained substantial knowledge on the topic. She has contributed to a number of peer-reviewed articles spanning a wide array of topics and works as a freelance writer trying to make scientific knowledge accessible to the public.