The short version
- Lean on fasting as a tool, especially when holidays, traveling, vacations, and other occasions disrupt your normal eating routine. Regular fasting can also be beneficial, especially for those with diabetes or struggling to lose weight.
- Start with a 12-hour fast to trigger ketosis and work your way up. Eventually aim for 16+ hour fasts to activate the powerful impacts of autophagy (cellular clean up).
- Women should only do longer fasts (15+ hours) at the beginning of their menstrual cycle through ovulation, then shorter fasts (12-14 hours) from the first day of the menstrual cycle through ovulation.
While I’m serious about my commitment to minimizing processed foods, limiting sugar, and eating low-carb, sometimes life happens and I have less control over what I’m consuming. It’s nice to know that fasting is one option for supporting my body in those circumstances.
Intermittent fasting
The 4th milestone in my health journey has been experiencing the benefits of fasting. I’ll start by saying that I don’t practice intermittent fasting all the time. Most of the time, I simply eat intuitively by listening to my body and only eating when I’m hungry (though this often results in natural periods of fasting).
Plenty of people intentionally use intermittent fasting regularly, and that’s incredible! If you try it and find that a consistent fasting schedule works for you while still allowing you to eat enough nutritious food, you may decide to stick with it. A regular fasting regimen may be especially beneficial if you have diabetes or are struggling to lose weight.
Personally, I tend to turn to fasting when I have less control over what I’m eating. Around holidays, traveling, vacations, and the occasional cheat meal (when I don’t have access to the ingredients lists or full control over food quality) I can at least control my eating window. This gives my body a break from processing foods of questionable quality, and allows some healing to take place.
That’s because fasting is a powerful tool that helps our bodies repair and reset. Among many positive effects, research shows that fasting may reduce inflammation.1 Recall our discussion on the importance of minimizing inflammation in Step 3. And there are numerous benefits to fasting that are only beginning to be discovered.
We know that ketosis begins 12 hours into a fast,2 with greater ketone response the longer you fast. In other words, we can trigger ketosis by fasting for 12 hours regardless of what we eat. Let me emphasize that this is not an endorsement for eating garbage all the time, but rather a piece of wisdom allowing us to tap into this strategy when we’re less in control of what we’re able to consume. And actually, fasting after eating junk is much harder. Speaking from experience, the hunger pangs feel stronger! But I still practice it in those cases to alleviate my body from the burden of unknown food contents.
Now, there are different types of fasting. If you’re new to it, consider starting with a 12-hour overnight fast and gradually working your way up (consume zero calories – water is okay).
When I am able, I aim for longer fasts (at least 16 hours), which begin the process of autophagy. Autophagy is the cellular process through which the body breaks down and recycles damaged or unnecessary cellular components. It’s like your body’s built-in clean up mechanism. At the very least, it removes damaged cells and reduces inflammation. Research is ongoing, but it potentially clears out fat, viral, and even cancerous cells. The longer the fast, the more benefits.
Women and fasting
I need to call out that men and women should approach fasting differently. Men can practice it daily and often continue to see benefits.
However, since women experience hormonal changes throughout the course of a month, we have to be more mindful of when to fast, and when not to in order to support our hormones. To put it simply, we can leverage longer fasts from the first day of our menstrual cycle through ovulation. After that, fasting for no longer than 14 hours is recommended.3 Postmenopausal women should follow a fasting cycle by marking the first of the month as the first day of their cycle.
For a wealth of knowledge on this topic, I recommend you check out Dr. Mindy Pelz’s YouTube channel and her book Fast Like a Girl.
A personal note: This reflects my experience, not medical advice. Nutrition changes can affect health conditions and medications, so bring your questions to a qualified professional who knows you.