When Does Ketosis Start When Fasting?

So, when does ketosis start when fasting?

We will definitely get to that, but first let’s get a quick understanding of what ketosis is and why we would want to be ketosis. And of course, how to know if we are in ketosis so we can better understand how to get there when we want to.

First, what is ketosis?

So, I am not a doctor so I can’t give you any medical advice nor would I ever want to. Whenever I present any medical related information, I always provide you with links to the same information I’m reading for my own purposes for you to consider. Obviously, nothing you read here should ever be a substitute for medical advice from a health professional. 🙂 And I’ll warn you now, doctors are not always in agreement when it comes to ketosis.

According to Medical News Today, “When the body does not have enough glucose for energy, it burns stored fats instead. This results in a buildup of acids called ketones within the body. In normal circumstances, the body’s cells use glucose as their primary form of energy. People can typically obtain glucose from dietary carbs, including sugars and starchy foods.” (a.k.a. everything I like to eat.)

When you’re in ketosis, that literally means that your body has burned through the carb related glucose. Now, your body is burning fat for energy.

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Why do we want to be in ketosis?

Now that we understand that getting into ketosis requires effort, why do we want to be in ketosis? If you’re like me, the fat burning is definitely attractive. Most if not all of the information I’ve read about ketosis mentions weight loss as a benefit. And I’ve experienced that for myself! But it’s clearly more than just weight loss.

Livestrong states that “in addition to helping you lose weight, ketosis may also increase your energy, improve your concentration, decrease inflammation and improve your blood sugar markers, reducing your risk of developing diabetes. A study published in the journal Seizure in 2014  linked ketosis to a slower progression of Alzheimer’s disease.

Healthline confirms that the “possible benefits of ketosis include weight loss and improved blood sugar management.”

And DietDoctor concurs with “being in ketosis may help you feel less hungry and promote weight loss.”

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How do I know I’m in ketosis?

So, if we’re going to put in the effort to get into ketosis, then we want to know when it happens. Because, it’s different for everyone! Two people can do the exact same thing but the onset of ketosis will  be different.  The key is to identify when YOU are in ketosis. From there, you can figure out the formula unique to your body to get there again. I’ve put together a list of items that can help you identify your ketosis sweet spot.

The Ketoscan mini is a portable breath analyzer that measures the ketone level in your breath. But it doesn’t stop there like most ketone breath analyzers do. It also helps calculate your body fat burning rate as well as your optimal ketosis state.  Plus, and this is a big plus, the Ketoscan has an app that lets you track your ketone levels and your weight. And you can also leave comments and track your calories with the photos of the food you ate.

Other ways to track your ketone levels:

According to Healthline, the most reliable way to measure your ketone levels is to use a blood ketone meter. You use a lancet and a blood testing strip to collect a small blood sample from your fingertip. According to the folks at KetoBM, this blood ketone monitor was designed to be the most accurate, user-friendly ketosis blood test meter on the market. And only a tiny blood sample is all that is needed.

When I was doing the keto diet, I used urine test strips to track my results. At the time, they didn’t have the breath analyzers or I probably would have gone that route just for convenience. The urine test trips are less expensive and actually make going to the restroom a little more exciting! 😉

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When does ketosis start when fasting?

So if you’ve read this far, you know that it’s impossible to give an exact time frame of when ketosis starts. Otherwise, we wouldn’t need keto tests.

Most of the intermittent fasting timelines out there (including the Women Who Fast app) state that around hour 12 of a fast, the body may start converting fat into ketones. And then between 18-24 hours, ketosis may begin. While this is certainly the case for some people, if you are regularly consuming carbs leading up to the fast, it’s going to take longer than that to rid your body of it’s glucose stores.

In fact, this transition could take anywhere from 48 hours to one week if you go into your fast chock-full of carbs! A fast of this length is referred to as “extended fasting” and we certainly recommend you consult a health professional before trying something like this.

An easier way to get into ketosis

A more realistic method would be to spend two days on a low-carb diet (if that’s safe for you medically) and then start ketone testing halfway through your fasts and see where you are. If you decide to do low carb for a couple of days, I would recommend you choose days when you aren’t meeting friends for lunch. I also think it’s easier to be successful with this if you plan out every single thing you are going to eat during your low carb days.

Low carb for me is 30 grams or less per day, but please do your own research and consult with your doctor if you are unsure.

To do this, just look on Pinterest for some low carb recipes that look good to you. Shop for your food beforehand and be totally prepared before you start. I say this because your mind will start playing little tricks on you in the early hours of a low carb diet. The ‘ole “there’s nothing here I can eat, so I’ll start tomorrow” is my mind’s favorite trick.

If you aren’t already exercising, throw in some light activity during your low carb days. Exercise requires energy, right? And the whole goal is to burn through the glucose in your body to get into fasting sooner.

The key is to experiment to find out what it takes to get you into ketosis. It will always require burning through the carbs you’ve consumed.  Combining intermittent fasting, low carbs and light exercise is a great way to find your ketosis sweet spot.

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I’m in ketosis, now what?

Once you find yourself in ketosis, you then have a decision to make. If you want to spend a couple of days there, continue with the low carb diet and intermittent fasting to maintain ketosis. Or perhaps you just want to spend a few hours there once in a while? Whatever you decide, be sure to keep track of how you got there so you know how to do it next time.

I will say, the first few days of a low carb diet are the hardest. So once you get there, you may decide you want to continue doing low carbs for awhile. If that’s cool with your medical status, I say go for it. Again, Pinterest has tons of great low carb recipe ideas.

So, when does ketosis start when fasting for you? Please drop me an email at support@womenwhofast.com and let me know about your experience. Happy Fasting!