Intermittent Fasting & Ketosis Controversies, Pros and Cons: What does the data say?!

**This is not intended to be medical advice, and always check with your doctor before implementing specific fitness or dietary changes.**

We’re diving into Intermittent Fasting (IF) and ketosis! Let’s discuss the misconceptions, the pros and cons! 

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INTERMITTENT FASTING

Intermittent Fasting (IF) typically refers to only eating within about an 8 to 12 hour window of the 24 hours in a day, and fasting the remaining 12 to 16 hours. 

There are a lot of unsubstantiated claims in regards to IF and ketosis. For example, oftentimes the benefits touted for these diets are actually attributed to the CALORIC RESTRICTION part of the diets. In other words, certain aspects of these diets can make it easier for some to eat fewer calories (more on this in a minute). This reduced calorie intake is actually what’s responsible for many benefits including weight loss, reduced inflammation, cleaning up of worn out body cells (known as autophagy) and fine tuning of bodily processes. Research is very clear that caloric restriction and reduced body fat is one of THE BIGGEST factors to bring about positive health changes! Many of the same benefits that people think are magical parts of IF and ketosis can be achieved whether that caloric restriction is achieved through intermittent fasting, ketosis, or just a plain old boring calorie deficit and fat loss (Bales, 2013; Napoleão et al., 2021; Wei, 2022; Weiss, 2011)! 

INTERMITTENT FASTING NEGATIVES:

1. Going too long without food can be perceived by the body as too stressful. This stress response causes cortisol to increase which leads to belly fat gain and muscle loss (Kim et al., 2021).
2. If you exercise while fasted, research shows not only does exercise performance suffer, but you’ll experience either greater muscle loss or reduced muscle building compared to if properly nourished pre-workout (Aird, 2018; Zouhal, 2020). This muscle reduction leads to a slower metabolism.  

1. So if you’re wondering: “You’re telling me that if I go into an intense workout fasted, while I’m trying to build muscle my body will just be breaking it down?!” For many people YES! I especially advise against fasted workouts for those under high stress due to elevated cortisol, and it tends to be even more unfavorable for FEMALES versus males due to hormonal differences. Just to be clear, I’m not saying you can’t build muscle if you choose to workout fasted, because you can! But according to research it is likely not optimal, particularly for intense exercise! Some people will supplement with amino acids when working out fasted to preserve muscle mass. 

We discuss more IF cons in the “Charge Up Challenge” program in the NuTriDay app. 
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INTERMITTENT FASTING BENEFITS:

1. You might find IF easier to achieve a caloric deficit due to individual preferences and your unique biochemistry
2. IF may improve blood sugar & insulin sensitivity for certain people (Cho, Hong & Kim, 2019), and therefore indirectly help with weight loss and health

We discuss more of IF pros in the “Charge Up Challenge” program in the NuTriDay app.  

THE KETOGENIC DIET

The keto diet is a high fat, low protein and severely low carb diet that causes your body to convert fat into ketones which can be used as fuel. To do it right, you should be eating about 80% of your total calories from fat, about 10 to 15% from protein and about 5 to 10% from carbs. Most people do it wrong and don’t eat nearly enough fat! You really have to food track in the beginning to know if you’re doing it right. And if you really are a nerd like me, you can buy a glucometer and ketone meter on amazon with the strips to test your glucose and ketone levels (CLICK HERE to check them out) to know if you’re actually in ketosis.  
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KETO MISCONCEPTIONS

Recently, the keto diet surged in popularity, but did you know the initial intention of ketosis is to help those with epilepsy and other neurological disorders? Somehow today its primary purpose made its way to the cover of “Muscle and Fitness” magazines! 

Let’s discuss the misconstrued keto fat loss claims…When you first go on the keto diet, you WILL lose about 5 lbs of WATER weight… not fat! For every gram of carbohydrates, your body holds onto between 2.7 to 3 grams of water… hence the name carboHYDRATE! And guess what?! As soon as you eat carbs again…all that water weight comes riiight back 😉

One of the biggest keto misunderstandings… People claim you magically lose more fat from ketosis because your body is this fat burning machine gobbling all the body fat away! This gives people the impression they can eat whatever they want and still lose weight! Not exactly! Yes, the statement “You burn more fat in ketosis” is true… but that’s because you’re also INGESTING more fat! So you’re not necessarily burning and LOSING more STORED body fat. And you're certainly not losing ANY stored body fat if you’re in a net caloric surplus! 
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KETO NEGATIVES

Now let’s touch on some of the negatives of ketosis:

But first an important point… the negatives of Ketosis usually don’t surface immediately, but they rear their ugly head OVER TIME! So someone might start keto and feel great.. But after a few months or maybe even a few years, not so much! …

1. Large scale research studies have clearly shown that Keto is suboptimal if engaging in intense exercise (Ashtary-Larky, 2022); It favors muscle loss & decreased performance for following reasons:

• When activity intensity increases, the body needs carbs – specifically glucose – as a quick fuel source. The pathways that use fat to create energy are much slower than the pathway that uses carbs to produce energy. This is a scientific fact that’s not up for debate. Well, when you’re in keto you’re eating practically no carbs, or glucose!
• It turns out that the body has a way to convert its own muscle tissue into glucose. Yes, you end up breaking down your own muscle to convert to glucose to produce energy. Seems counterproductive, and indeed it is, but this is what happens. This describes the process that some of you may have heard of called gluconeogenesis.
• A large-scale systematic review & meta analysis showed increased muscle loss and decreased strength for keto and low carb peeps compared to people eating a balanced diet that included carbohydrates (Ashtary-Larky, 2022). 
• Again, like i said with IF, I’m not saying you CANNOT build muscle, it just won’t be optimal, and you would almost certainly gain more muscle if nourished properly with carbs prior to a workout

2. Ketosis means you're essentially having little to no fruit… and fruit is loaded with great micronutrients essential to our health. Not to mention resistant starches in carbs like potatoes and lentils have profound positive impacts on our gut bacteria - which determines so much about our overall health (Maier et al., 2017)! Again there’s that pesky theme of “balance” resurfacing! 

We discuss more keto cons in the Charge Up Challenge NuTriDay app. 

KETO BENEFITS

To give ya the accurate explanation for how keto may help to lose fat, let's discuss 2 of the benefits of keto… 

1. First of all… to lose fat, you must be in a caloric deficit! Many find this is easier to do while in ketosis because fat is very satiating and we’re discovering that the ketones themselves may have a satiating effect (Kirkpatrick, Bolick & Kris-Etherton, 2019)! 
2. Ketosis increases what’s known as your “metabolic flexibility” – which basically means it helps you to become better at burning fat for fuel, sparing you from burning through muscle for fuel in specific situations! For example, let’s say you’re used to eating a high carb diet. You’re training your body to rely on using more carb for fuel. But now let’s say you take on the 3 to 5 day bone broth keto challenge taught in the Charge Up Challenge program in the NuTriDay app and continue to incorporate it once every month or so… the more you do it, the more you train your body to use fat for fuel! Then when you’re in a caloric deficit, your body is less likely to break down muscle tissue to convert those amino acids into glucose for energy… Instead your body is more likely to use its stored fat for fuel!

How can we get benefits of keto and IF without suffering the negative consequences? 

We discuss how to do it and more pitfalls to be aware of in the Charge Up Challenge program in the NuTriDay app. 

Plus, I will lead you through how to do a 3 to 5 day bone broth/vegetable ketosis cleanse during the Charge Up Challenge program! I’ve been doing this about once every month or two for the last 7 years and it has been transformational in my health journey! The program e-book has you covered on more nerdy (but practical) details behind keto and IF for those who are interested!

P.S. You may have heard of the “keto flu.” This refers to the common energy drain, feelings of weakness and sometimes headaches – very common when someone tries keto for the first time or two. This is because your body is so used to having carbs for fuel and hasn’t quite learned to flip the switch to create ketones out of the fat to use that for fuel instead. The keto flu often starts on day 2 and sometimes lasts through day 3. But if you push through, you should feel a magical shift, a clean energy and great mental clarity and focus. 

We discuss how to combat the keto flu in the Charge Up Challenge program in the NuTriDay app.

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