Intermittent Fasting on Keto? Here’s What you Need to Know

Intermittent fasting has gained traction in the past few years as a popular weight loss tool. But can it overlap with the Keto Diet? There are some potential benefits to intermittent fasting, including weight management, reduced inflammation and blood sugar control

So, why pair these two at all? Well, because Keto and intermittent fasting can be quite complementary. In fact, Keto can help regulate your appetite, making intermittent fasting easier to sustain.

Also, combining these two can help you burn excess body fat in less time. This is because when the body is in a state of fasting, it switches its fuel source from carbs to fats, which is also how keto works.  Because of this, intermittent fasting may help you reach ketosis faster. Intermittent fasting also promotes heat production, or thermogenesis, in the body, which boost the metabolism. This can help shed stubborn stores of excess body fat. 

Curious about mixing these two? Well, you’re in luck! Here are five quick tips for intermittent fasting on keto.

Tip 1: Think 16/8

Intermittent fasting is described as cycles of caloric restriction (or fasting) alternating with periods of eating. Just how long each of these cycles can last really varies. One of the most popular methods is the 16/8 intermittent fasting

So, think 16 hours of fasting, with an 8-hour window in which eating is unrestricted. This allows people to eat from 9 a.m. to 5 p.m., for instance, while fasting otherwise. The eating window should be one that makes the most sense for you, your body and your life. If 8 hours is too restrictive, some people find that eating during a 9- or 10-hour window and fasting for 15 or 14 hours works better for them. 

Now, following a keto regimen during that eating window can help put your body in ketosis sooner. This is because both intermittent fasting and the Keto Diet lead your body to naturally start burning fat instead of carbs as fuel. Blending intermittent fasting with a Keto Diet is sometimes called Cyclic Keto.

Tip 2: Find your Flow 

Find what works for you. This is going to take some trial and error–but everyone’s body and needs are unique. You can try easing into the 16/8 baseline described above and then find your perfect happy place. But it may be that your style is more of a 14/10, and that’s okay.

You should also know there are other types of intermittent fasting diets, like the 5:2 Diet, with five days of regular eating periods followed by two days of fasting. It is important to note that the periods of fasting restrict intake only to about 25% of regular caloric intake (so, 500 for women and 600 for men). Another variation is the 6:1, which follows the 5:2 pattern but restricts caloric intake only for one day instead of two. These variations allow you to eat smaller amounts during the fasting periods, instead of ruling out food completely. These may be good options for those new to fasting and may help make fasting on Keto more sustainable, because you may not feel quite as hungry.

Tip 3: Maximize your Eating Window

Because you’d be restricting the time frame in which you eat, it makes it that much more important to eat well when you do eat. Luckily, healthy and keto-friendly fats, such as those that come from avocados, nuts and plant-derived oils, will be your friend during your eating window. This is because healthy fats pack calories, which you’ll need. Blending healthy fats with protein can improve how satisfied you feel. 

Oh, and hydrate at all times! Most people try to drink about 8.5 to 13 cups a day, but listen to your body’s cues. Staying well-hydrated will also keep you feeling full during those cycles of fasting. It’s also important to hydrate when transitioning to a Keto Diet, as Keto can result in increased water loss from the body. 

The main takeaway is that your eating window should be taken seriously. This can help ward off feelings of sluggishness, muscle cramps or headaches, also known as the “keto flu.” While whole foods are how the body best absorbs nutrients, supplements may help meet all of your vitamin and mineral needs when doing intermittent fasting on keto. Most importantly, maximizing your eating window will also help ensure that you’re giving your body what it needs.

Tip 4: Ease into It

Know that it might take your body a little time to adjust to either diet. For this reason, it may be a good idea to try the Keto Diet first–if you feel it’s right for you–before you try both at once. This will allow your body to transition slowly and ease into it. Then, layer in intermittent fasting once you’ve got the hang of keto. Because Keto can help regulate your appetite, it might make it easier to get the hang of intermittent fasting.

To help you combine these two diets, it may also be a good idea to consider taking keto-friendly supplements. Keto-friendly greens powders and other mineral supplements can help maximize your eating window. Greens powders are simply powdered forms of vegetables such as broccoli, kale or spirulina. These can easily be added to smoothies or water.

Another supplement, MCT oil, may also help boost ketosis. Coconut oil is a natural oil that contains MCTs (short for medium-chain triglycerides). Concentrated MCT oil delivers a larger dose of ketone-boosting MCTs.

Tip 5: Have an Intention in Mind

It might help to know what you want out of this mix. Is it body fat loss? Blood sugar control? Enhanced athletic performance? Have those goals clear in your mind before you set out on this journey. This will help you make your way towards this goal and also to know when you’ve reached it. While Cyclic Keto may be a safe and useful tool to jump start your goals, its safety as a permanent, long-term diet just isn’t known at this time.

Remember, if you have diabetes or a heart condition, intermittent fasting and keto may not be for you. And if not done properly, fasting can be dangerous for anyone. As always, it is best to talk to your healthcare provider or registered dietitian before making any drastic changes to your diet. 

 

References:

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