Intermittent Fasting FAQs: Your 7 Most Common Question Answered

Dr. Nasha answers seven frequently asked questions about intermittent fasting.

Intermittent fasting has been used as a therapeutic tool for thousands of years. Spiritual leaders have used intermittent fasting to promote peace, Greek philosophers used fasting to sharpen their cognitive abilities, and nomadic humans practiced fasting regularly during periods of feast and famine.

Though fasting is nothing new to the world, it’s been quite unpopular in modern Western culture. Modernity encourages more of most things, and going without basic staples (such as food) flies in the face of our first-world cultural norms. We prefer to keep things the way we like them: plentiful and available on demand.

Over the past few years, though, fasting has become increasingly popular thanks to it’s profound health benefits. Fasting has been clinically linked to weight loss, improved blood sugar control, healthy brain function, and cancer prevention, to name a few.

But since intermittent fasting had become all the rage, we’ve been flooded with information—both accurate and inaccurate—about what fasting is and how to do it. Sometimes the sheer volume of information available is overwhelming, and if you’re new to fasting you might feel a bit stuck.

Below, I answer 7 of your most common questions about intermittent fasting so you can cut through the noise and decide if fasting right for you.

1. Isn’t it unhealthy to skip breakfast?

Skipping breakfast is not unhealthy, especially since most breakfast foods like cereals, bagels, and baked goods are loaded with sugar. Those things aren’t healthy any time of the day, let alone as a morning meal.

The common belief that breakfast is essential to jumpstart your metabolism and promote healthy brain function is also misguided. In fact, studies show that there is no difference in calories burned throughout the day between people who eat or skip breakfast. There is also clinical evidence that fasting enhances cognitive abilities and mental acuity. ^{[1, 2]}

2. Can I drink liquids during my fast?

Yes! Drinking non-caloric or low-caloric beverages is perfectly okay while you’re fasting.

In general, it’s important to keep in mind that water is most important liquid to keep you healthy. It’s essential to maintain proper body functions, keep your skin supple, and ensure your blood flows efficiently.

Here’s a little fact to put it into perspective: The average human can live weeks without food, but will expire after only a few days without water.

These are popular liquids to keep you hydrated and satisfied through your fast:

• Water (still or sparkling)
• Coffee
• Tea
• Bone broth

Technically, adding cream or coconut oil to your drinks breaks traditional fasting rules, but folks often find that adding flavor is more enjoyable. I say do it, but don’t over do it.

3. Can I work out while fasting?

Exercising while fasting is perfectly okay. Normally, the body creates energy through sugar, which is stored as glycogen in the liver. When you exercise while fasting, you’re likely to deplete those stores and your body will burn fat as fuel instead, which prompts weight loss.^[3]

Here are a few tips to guide your workout routine during a fast:

• Exercise at the beginning of your fast, rather than the end
• Stay hydrated by drinking plenty of water
• Keep your electrolytes up
• Work out in small windows so you can monitor your body

The key is to listen to your body. If you feel dizzy or lightheaded while working out, it might be time for some water, electrolytes, and a meal. If you’re looking for additional tips or to develop an individualized workout routine that’s right for you, check in with your healthcare provider.

4. How does intermittent fasting affect my hormones?

When you fast, your body responds by signalling changes in two main hormones: insulin and human growth hormone. Here’s how these key hormones play a role in intermittent fasting:

• During fasting, human growth hormone (hGH) levels increase. This helps you lose weight, build muscle, and generate new proteins for cell repair.^[4]
• During fasting, insulin levels drop dramatically. This helps make body fat more accessible as a fuel source, since low levels of insulin signals to the body that there isn’t enough glucose to power cellular activity.^[5]

The modulation of these two hormones is key to some significant health benefits of intermittent fasting. They help the whole body switch from glucose energy production to adipose or fat energy production.

5. Who should avoid intermittent fasting?

Under the right circumstances, fasting has profound benefits to the body. It encourages metabolic agility, cellular repair, and even has profound effects on genes related to longevity. But intermittent fasting isn’t for everyone.

Consult your healthcare provider to determine if intermittent fasting is right for you especially if you:

• Have diabetes: While intermittent fasting improves insulin sensitivity and has proven beneficial to folks with type 2 diabetes, you’ll want to chat with a healthcare professional to monitor your blood sugar levels. To chat with a professional, check out Virta Health. They help folks treat type 2 diabetes with low-carb, Keto, and fasting approaches.
• Have a history with disordered eating: Intermittent fasting may encourage an unhealthy relationship with food if you’re prone to disordered eating behavior.^[6]
• Are pregnant or breastfeeding: According to the Mayo Clinic, breastfeeding women benefit from an increase in calories, since women need and extra 300 to 500 calories per day in order to maintain milk production. Restricting calories may be unwise in these circumstances.^[7]
• Take regular medications: If you take medications with food, you’ll want to check with your doctor to ensure that fasting won’t interfere with your regular routines.

It’s advisable for everyone (whether you have meet the above criteria or not) to check in with a healthcare professional before fasting. To speak with a metabolically trained doctor, click here.

6. What if I’m hungry during fasting?

In the beginning, feeling hungry during fasting is common. As your body gets better at switching between sugar and fat sources, however, you won’t feel hungry as often.

In fact, most people are amazed at how efficiently their body works when they’re in a fasted state. If you’re still experiencing frequent hunger, it’s okay. It just means you have some work to do to become metabolically flexible. Keep at it.

7. How should I break my fast?

After fasting, it can be tempting to dive right into a whole lot of unhealthy food. But doing so will undermine the success of your fast and will likely just give you a stomach ache.

I recommend having a small, healthy snack to break your fast, such as a handful of nuts or an avocado. Give yourself thirty minutes to digest, and then go ahead and have a regular meal.

Set yourself up for fasting success

Intermittent fasting is a therapeutic tool that takes some time to master. It’s okay if you’re not a fasting pro on your first go. With practice, patience, and healthy habits in-between fasts, you’ll master the metabolic approach to health in no time.

I always tell my patients to approach therapeutic tools with this simple method: test, assess, and address. Make your body a living laboratory. Test a fasting method, assess how you feel, and make changes accordingly. And always chat with your doctor about changes to your wellness routine.

To talk with a metabolically trained professional, click here. These physicians are experts in the metabolic approach to wellness and would be delighted to speak with you and help you achieve metabolic flexibility.

For more information on fasting, check out our article “Intermittent Fasting for Beginners: Everything You Need to Know to Get Started.”

Or drop you questions in the comments! I’d love to answer any other questions you have about fasting and metabolic wellness to get you started on the right foot.

References:

1. https://pubmed.ncbi.nlm.nih.gov/24847666/
2. https://pubmed.ncbi.nlm.nih.gov/18779282/
3. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5050386/
4. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC329619/
5. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6521152/
6. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5959807/
7. https://www.mayoclinic.org/healthy-lifestyle/infant-and-toddler-health/expert-answers/breastfeeding-and-weight-loss/faq-20094993