Intermittent Fasting FAQs: Your 6 Big Questions, Answered


By Alyssa Kessel, RDN, LD, Expert Dietitian

Intermittent fasting is a popular trend right now, and I get a lot of questions from patients about how they can incorporate it into their meal plans as they progress. If you haven’t heard much about this trend, take a look at my beginner’s guide to intermittent fasting.

For those that have read the guide and are interested in learning more, I’ve compiled some of the biggest intermittent fasting FAQs I hear from patients.

Will my metabolism slow down if I’m fasting?

No. This is a common myth about fasting that comes up a lot. A number of studies have proven fasting doesn’t slow down the metabolism; in fact, it may in fact slightly speed it up! This happens because of a release of hormones that activate your sympathetic nervous system when you fast. [STUDIES?]

How do I manage my hunger?

The good news is that hunger typically comes and goes in waves. Most people worry that their hunger will continue to build until it’s intolerable, but that doesn’t happen. If you stick it out, it’ll pass and you can successfully fast. One trick I use is to drink coffee, tea, or water to help suppress that appetite for a little longer.

Can I exercise during fasting?fasting exercise

Absolutely! Exercising during a fast is perfectly fine. Some studies have even shown that fasting during a workout can help burn more body fat. That being said, it’s still important to listen to your body. If you find that your body feels too weak (or tired) from fasting to work out, then take care of your nutrition before hitting the gym. The best way to avoid this scenario is to get your workout done in the morning vs. at the end of the day where you’ve been fasting for 16 hours.

Will I lose muscle?

During fasting, your body will use your stored fat for energy. As with any weight loss method, however, loss of muscle mass is a possibility. I recommend eating an adequate amount of protein before and after the fast, as well as exercising regularly (especially with resistance training) to help maintain your muscle mass.

How do I know it’s working?

body fat percentage

This is a great question. If you’re choosing intermittent fasting for weight loss, I recommend taking a few measurements:

  • Body fat %. Lots of scales provide this feature now.
  • Inches around your waist. A simple fabric measuring tape will do the trick.
  • Bonus: before/after pictures. Pictures can help you see any changes, so take some from the front, sides, and back. The tighter the clothes fit, the more you’ll see the changes.

If you’re choosing intermittent fasting for health reasons over weight loss, I suggest journaling to keep track of your symptoms or how you’re feeling overall.

What are the possible side effects?

Some people might experience headaches, but these tend to disappear after the first few times fasting. Constipation is common, because there’s less going in (which means less coming out). Other side effects include dizziness, heartburn, or muscle cramps. Drinking water can help improve these symptoms.

Hopefully, I’ve answered some of your big fasting questions. Intermittent fasting isn’t for everyone, but if it’s something you would like to try, you can call us at 513-791-9474 or fill out a consultation packet to get started in one of our programs.

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