Intermittent Fasting Results During The Keto Diet

Updated August 23, 2021 by Iulian Ionescu | Read Time min.
keto intermittent fasting

If you’ve been following me on Facebook, Twitter, or Instagram, you know I’ve become quite obsessed with intermittent fasting and the Ketogenic diet lately. It’s not just a phase; it’s a way of starting a new chapter of my life. A healthier, happier chapter. At the time of this post, I am 112 days into this journey, so I approach the 4-month mark. So far, everything is going according to plan, which is surprising to me, but I’m keeping my fingers crossed.

This article will talk about the second leg of my journey: adding intermittent fasting to my Keto diet. But, before diving into that, let me do a quick recap of what has happened so far.

Last month, I posted an article on my keto journey to weight loss and a healthier lifestyle. It was meant to be the first installment, and in that article, I talked about my life before the diet, when the diet started, and where I was about 70 days into it.

As you will see below in the statistics section, a few weeks before I wrote that article, I had hit a bit of a wall. A stale period where even though things were good, there was stagnation and no progress. That sounded like the perfect time to shake things up a little bit, so I decided to add intermittent fasting (aka IF). This article is about that experience.

fasting food control

What is Intermittent Fasting?

First, let’s start with “fasting.” What is fasting?

intermittent fastingThe official definition for fasting is the willing abstinence or reduction from some or all food, drink, or both, for a period of time. Most people are aware of fasting from a religious aspect. Many religions incorporate fasting into their methods of worship. Fasting is sometimes used by people protesting a certain cause or to make a statement. In other situations, fasting is required, for example, before a medical procedure that involves anesthesia.

In any case, in plain English, fasting means not ingesting any calories. Basically, no eating (or drinking).

I have to tell you, and you can ask my wife for proof: I’ve lived my entire life without being able to understand fasting. I couldn’t fathom people not eating for five hours. I’m not even talking about twelve, fifteen, twenty hours! That sounded insane to me. My body wasn’t going to take that. If I hadn’t had my breakfast or generally pump up my blood sugar every two to three hours, I’d feel terrible. Forget about being “hangry.” I was an f-ing mad dog! And then… it all changed with intermittent fasting.

What is intermittent fasting, then? And how is it different from just fasting? First of all…

…Intermittent Fasting IS NOT:

  • Calorie restriction
  • Starvation
  • A magic pill or a short-term solution

…Intermittent Fasting IS:

  • Timing of food
  • Eating the right type of food
  • A long-term commitment

If you look at a 24-hour period, intermittent fasting splits this period into two parts:

  • Feeding time: 8 hours
  • Fasting time: 16 hours

This is the reason why it’s called intermittent. Because you go with it in cycles: feed, fast, feed, fast, feed, fast, etc…

If you think about it for a bit, everybody is doing a form of intermittent fasting. When you go to sleep at night, no matter what time, you stop eating. That goes on until you wake up and you have your first meal. Which, by the way, is called “breakfast,” as in break your fast. The intermittent fasting method simply prolongs the fasting time.

At a very high level, this is how our body works for a full day:

During the day (or feeding time):
Eat Food –> Increase Insulin –> Store sugar in liver –> Produce Fat in Liver

During the night (or fasting time):
No Food –> Decrease Insulin –> Burn stored sugar –> Burn fat

By this simple equation, the longer you can maintain the second part, the more fat you burn.

And here comes the amazing kicker: combining Intermittent Fasting with Keto.

As you know from the previous article, the ketogenic diet’s basis is lowering carb intake, which in turn reduces insulin levels, which forces the production of ketone bodies, which then take fat and turn it into energy (which is why you eat so much fat on the keto diet). So, imagine what happens if your body is already “fat-adapted,” meaning it’s producing ketone bodies all the time. All cells are adapted to that form of energy, AND you add intermittent fasting.

There’s a huge compounding effect. That last piece: burn fat, will increase tenfold. Also, since you are no longer introducing fat in your body during the fasting period because you are not eating, your body MUST burn your existing fat for energy. It’s a potent combination.

To learn more about some of the specific types of intermittent fasting and how to apply them, follow my beginner’s guide to intermittent fasting.


fasting plan ideas

Benefits of Intermittent Fasting

Here’s a quick list of science-backed benefits of intermittent fasting. You can read more about these by following the links in the below Resources section.

  1. Changes in the function of cells and hormones—during the fasting state, there are many processes that our body is going through, and they result in cellular repair and growth hormone production, which stimulates muscle development.
  2. Reduces insulin levels and prevents insulin resistance—a huge benefit, especially for people at risk of Type II diabetes. By reducing insulin levels, the body is protected from low blood sugar.
  3. Helps burn belly and thigh fat—There are parts of our body where fat is really hard to burn. It’s usually thighs and buttocks for women and belly and back for men. During fasting, our body reaches into those reserves and burns that fat for energy. This is accelerated if you introduce exercise in your daily routine.
  4. Prevents oxidation—Free radicals in our body damage DNA and contribute to mutating cells, leading to various chronic diseases and cancer, and accelerates aging. By fighting oxidation and eliminating free radicals, our body is shielded from those negative effects.
  5. Reduces inflammation—Inflammation in our body is at the core of many diseases and contributes to feeling fatigued and in pain. Studies have shown that intermittent fasting reduces the overall inflammation in your body.
  6. Improves heart health—There are many risk factors for heart disease: high blood pressure, high cholesterol, high triglycerides, and more. Intermittent fasting helps lower blood pressure, regulates the LDL cholesterol level, and reduces triglycerides, thus lowering the risk for heart disease.
  7. Helps with cancer prevention—By fighting free radicals, reducing inflammation, and repairing cells, intermittent fasting contributes to cancer prevention and improves the ability to withstand severe chemotherapy treatment.
  8. Improves brain health—Several studies have shown that intermittent fasting helps regenerate nerve cells and regulate several hormones linked to depression and other mental disorders.
  9. May help prevent Alzheimer’s Disease—Studies on animals have shown that intermittent fasting delays the onset of Alzheimer’s Disease and reduces its severity.
  10. Helps increase lifespan—Last but not least, and probably the most important of all – intermittent fasting increases lifespan and delays aging.

How do I use intermittent fasting?

I started intermittent fasting because I hit a plateau, which you will see explained briefly. As soon as I implemented it, I started to feel its benefits:

  • Fewer food cravings
  • Increased focus and concentration
  • Elevated fat burn and weight loss
  • More energy
  • More time

The first five days, it was a bit rough but not by a lot. I have to say that the physical difficulty was far less than the mental one. By this time, my body was fully fat adapted. I was in deep ketosis, which means that my body produced enough ketones to convert my own fat into energy. So, my body really didn’t need that much food. It was more of a mental struggle.

It’s like smoking and having to give it up. For the past 40 years, I’ve been used to eating one or more snacks every few hours, as my life depended on it. With IF, things were different, and my brain wasn’t ready to cope with it. I had to fight through it. But once I got over it, it became effortless, and the results showed up right away.

This is how I structure my weekdays:

  • The first meal of the day at 12:00 pm
  • Last meal of the day at 8:00 pm

During this time (12 pm – 8 pm), I eat ALL the calories I need, and I maintain the proper macro %s. I make sure I hit my protein and fat goals and keep my carbs to a minimum. But the calorie count is essential. I know that it’s very tempting to say: well, I’ll go on keto, jump into IF, and then also cut 30% of my calories. The effects will be amazing! NO, they will NOT. If you reduce the calories simultaneously, you will slow down your metabolism, prevent intake of essential vitamins and minerals, and go into all kinds of problems (hair loss, mood swings, etc…). Calorie limitation is not a good way to go…

Also, note that I only do intermittent fasting Monday through Friday. During the weekend, I have three regular meals spread over the morning, afternoon, and evening.

In popular terms, my method is also known as “skipping breakfast.” Depending on your own schedules, you may choose a different schedule. For instance, you could skip lunch or dinner. Regardless, make sure that you have eight continuous hours during which you eat and sixteen continuous hours during which you do not eat. It’s as simple as that.

How to break the fast?

ketogenic diet breakfastOkay, so I wake up at 6 am, and I exercise in a fasted state. Between wake up and noon, I am cautious about keeping myself hydrated. In addition to lots of water, I drink coffee and green tea, which have multiple health benefits besides fat loss.

Around 12 pm, I am getting ready to break my fast. This is the series of events:

  • I start with one cup of bone broth, slightly warm. Bone broth has a wide range of health benefits being packed with nutrients, but one of the greatest is that it contains large amounts of collagen. Collagen is an important protein that basically keeps us together. It’s the glue that makes our skin tight, our tendons strong, our nails hard, and so on. However, collagen in our body decreases with age, and the older we get, the more it becomes obvious (loose skin, frail joints, loss of hair, etc.). Because the stomach is very clean after the fasting period, the absorption of nutrients and minerals is optimal. By ingesting bone broth at that moment, you will experience a very efficient absorption of collagen, which will help improve your skin, nails, hair, and so on.
  • I follow with apple cider vinegar. I usually put two tablespoons in the bone broth and drink it all together like a soup. You can also buy the bone broth from Kettle Fire, which already has apple cider vinegar in it. The vinegar will help balance healthy pH levels, kill bad bacteria in your gut, and stabilize blood sugar. Another great combo is apple cider vinegar with lemon juice and a pinch of cinnamon. And please, for the love of God, don’t drink it from a spoon. It will burn your throat. Put one or two tablespoons in a full glass of water (or in your bone broth).

Once these are in, I wait for about ten minutes, and then I take any supplements that I need for the day – my daily vitamins, minerals, etc. This is by far the absolute best time to take them. Your body will absorb them very efficiently.

With all these over, I’m very close to my first meal. But before, I take one spoon of MCT Oil. This will signal to my body that fat is about to come. It jump-starts the production of ketone bodies (because of the special way that medium-chain triglycerides bypass the digestive system and go straight into the bloodstream).

And that’s it. My fast is broken in about fifteen minutes, and my digestive system is “primed” for solid food. Note one thing: if you experience stomach issues like diarrhea after your first solid meal after a fast, it means that your body is not producing the proper digestive enzymes and doesn’t have the right gut bacteria. Consider taking a wide-range digestive supplement that also contains pre and probiotics. In time, you will adapt and won’t need them. But for a start… it will keep you out of the bathroom…

I like to keep the calories to about 500-700 kcal for my first meal, with a meager carb impact. Here are some of the foods that I combine depending on how I feel or what I have at home:

  • Boiled or fried eggs
  • Avocado
  • Sardines in olive oil
  • Bacon or pancetta
  • Butter (grass-fed)
  • Keto bread

My second meal of the day will be richer in leafy vegetables, some good carbs, and more protein. Sometimes, I add cottage cheese, but I generally try to keep dairy to a minimum.

Since I mentioned my second meal, another question that comes to mind is this: how many times do you eat during the feeding period?

There are several techniques here:

  • 1 meal per feeding period – this is too extreme and most likely won’t work for me.
  • 2 meals per feeding period – I do this about 60% of the time (approx. 700 calories meal #1, 1300 calories meal #2).
  • 3 meals per feeding period – I do this about 40% of the time (approx. 500 calories meal #1, 500 calories meal #2, 1000 calories meal #3).
  • More than three meals – highly not recommended; read why below.

If you recall from reading about the keto diet, the goal here is to reduce insulin spikes. Every single time you put food in your mouth that has calories in it, your insulin will spike. During the insulin spikes, your ketone body production will stop, and so will fat burn. This means that the fewer meals you eat per day, the less likely you will get out of ketosis. This is why hard-code intermittent fasters recommend a 1-meal per day program. For me, it just doesn’t work. But two meals per day is very doable. By the way, the 1-meal a day method is an actual thing; look into it: The OMAD diet. But I digress…

The Numbers

Of course, there was going to be a chart here. After all, without measurements, what are we? Below is a weight chart that spans a few years. The gaps are those where I haven’t kept proper data.

intermittent fasting on keto

The image is quite self-explanatory, but let me give you some details here:

  • pre-2011 – These were probably my fattest years. Around that time, I’ve been struggling with exercise and not getting below 187 lb.
  • 2011-2013 – My son was born in 2011, which was also when I started running. During this time, my weight dropped significantly, and my health improved significantly due to the benefits of running. At the end of 2013, I ran a hat-trick (5k + 10k + half marathon), and I set my goal to run a marathon in 2014.
  • 2014-2015 – In January of 2014, I got hit by a car crossing the street as a pedestrian. It was pretty rough, and for the next 1.5 years, I was not allowed to do any physical exercise, save for physical therapy. During this time, my weight just exploded. Besides no exercise, I was also eating like a pig.
  • 2015-2018 – In 2015, I joined Next Jump, a company in Manhattan where health and wellness are a central part of the company culture. I began exercising again and eating healthier. My weight dropped a little, but I still suffered from high blood pressure. By the end of 2017, I finally ran my very first marathon in Atlantic City.
  • Q1 2018 – In Jan of 2018, I left Next Jump, and I went through a period where once again, I wasn’t eating very healthy; I was drinking way too much alcohol, and I wasn’t exercising smartly.
  • April 2018-June 2018 – This is when the Keto lifestyle has begun. Look toward the end of June, and you can see a slight plateau.
  • June 2018 and after – This is when I introduced intermittent fasting. You can see how my weight took a steep turn. In combination with these, I’ve been working almost exclusively on my balance, mobility, and flexibility, and core strength through yoga, Pilates, and other similar exercises.

So, that’s where I am right now. What’s next?

I am going to continue with the keto diet + intermittent fasting through the end of September. During this time, I will keep on working on my balance and mobility. Once October 1st comes along, I will enter Phase 3: bulk up with lean muscle… More on that later…

Intermittent Fasting Resources

If you are looking to learn more about intermittent fasting and how it works with the ketogenic diet, I put together many useful resources to check out. Enjoy!


I recently learned about FitnessVolt, a leading website that provides up-to-date information on everything fitness. To no surprise, they have several great resources on intermittent fasting that will help you along your journey:

  • Intermittent Fasting Calculatorwill help you determine your IF schedule depending on your body and fitness goals.
  • TDEE Calculatoruse it to determine your total daily energy expenditure, the starting point of any nutrition plan, including intermittent fasting.

Now, before you go, I have…

3 Questions For You

  1. Have you used intermittent fasting before?
  2. What were your most successful lifestyle changes for weight loss?
  3. What are your overall challenges with weight loss?

Please share your answers in the comments below. Sharing knowledge helps us all improve and get better!



fitness, health, weight loss

  • Buna Iulian, ma documentam despre stilul de viata Keto si am gasit blogul tau. Inca mai tii acest regim, cum a impactat-o pe partenera ta? Ai depistat diferente intre cum au reactionat corpul tau sau al partenerei la acest stil de viata? Sper sa nu deranjez cu intrebarile. Numai bine, Luciana

  • I am on my weight loss journey and I agree that combined exercise and a healthy diet is important.

    It does not have to be 1000 steps or anything like that. Start with small things such as walking in the park. From there, build momentum and improve daily. Weight loss should be enjoyable and rewarding at the end. Also, small habits such as keeping fruit in the fridge and healthy snacks such as roasted almonds could give you a huge payoff in the long term.

    One other thing that can help is starting a diet journey with a written plan and a journal. You want to come up with a system that you can follow and adjust based on your situation. I keep a list of exercises, progress and food recipes that help me with my diet.

    I love tea! I keep a bunch of tea recipes in my journal. I benefited from the Red tea detox program. It has a bunch of ingredients that help to reduce hunger and production of stress hormones. It helps me to cut my binge eating habit that I have tried to get rid of since forever.

    Personally I follow the all in one guide from, they have the best Red tea detox recipes plus all the exercises and diet plan necessary to give you results in just 14 days. I hope this helps you and good luck in your weight loss journey.

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