What is Ketosis & the Ketogenic Diet? Only the Facts (and maybe some science-y stuff).

What is Ketosis & the Ketogenic Diet? Only the Facts (and maybe some science-y stuff).

There is a lot of chatter in gyms, blogs, and of course on Facebook about something called Keto or Ketosis.  It just so happens that at this time a couple of us at Catalyst are using the ketogenic diet (“KD”).  This entire subject matter can be very information dense and complex.  To help understand ketosis and KD a little bit better I think it is important to define a few key concepts and definitions of commonly asked questions.  After touching on these more “science-y” subjects I will bring you through some of the experiences (pros & cons) that a couple of us have had on KD.   There will be no claims about whether one lifestyle choice is better than another.   

To help you navigate this article it is broken up into 3 parts.  Part 1 is filled with definitions and key concepts, Part 2 is the experiences section (my own…) and finally, Part 3 is the conclusion. Feel free to skip around and read what interests you. 


Part 1: The Kind of Science-y stuff

You shouldn't feel like that guy after reading this... 

How does the body produce energy?
This whole conversation starts with how the body digests food and produces energy.  It is important to understand on a super basic level how our body makes energy on both a “conventional diet” and on KD.  Let’s start with a conventional diet-- the primary source of fuel is carbohydrates.  A person consumes carbohydrates in the form of fruits, vegetables, grains, and processed sugars.  Skipping over all the crazy complex reactions, those foods are broken down and produce glucose.  Glucose is then used by the body as fuel to help make energy. 

KD differs from a conventional diet because its primary source for fuel is fat and not carbohydrates.  Once again, skipping over all the crazy complex reactions, fat is broken down by the body to make ketones.  Since there is no glucose to use as fuel, the body will now turn to ketones as its primary fuel source to produce energy. 

Then what is ketosis?
“Ketosis is a state, achieved through significant reduction of carbohydrate intake (typically to less than 50 grams per day), at which point the body makes a fundamental change from relying on glycogen (lots of glucose stuck together) as its main source of energy to relying on fat as the primary source of energy.  In particular, the brain shifts from being entirely dependent on glucose, to being primarily dependent on beta-hydroxybutyrate – a so-called ‘ketone body.’  Ketone bodies are chemical structures made by the liver (also somewhat in the kidney) out of fatty acids, primarily.”  -Dr. Attia 
For more resources from Dr. Attia click here

What does the Ketogenic Diet entail?
KD, as a way to eat. is rather simple in concept.  On KD it is important to eat very little to no carbs and extremely high quantities of fat.  As a guideline, each meal should be broken down to the following percentages: 60-80% Fat, 15%-25 % Protein, and 5-10% Carbohydrates.  For optimal performance for very active populations the higher ends of the protein and carb range are a good idea.  The lower end of the percent range for protein and carbohydrates are recommended for more sedentary people.  For a good resource of common mistakes Click Here .  The title refers to athletes but I believe these mistakes are common among the beginner keto dieter as well. 


What is ketogenesis?
In simplest of terms ketogenesis is the breakdown of fatty acids by the liver (and kidney a little) to produce 3 ketone bodies: acetoacetate, beta-hydroxybutyrate, and acetone. Technically beta-hydroxybutyrate is not a ketone body (because it has an extra “OH” on the compound), but it can be broken down to acetoacetate and used in the body in the same manner as the other two ketones.  


How do you get your body into ketosis?
One of the fastest ways to get into ketosis is to participate in Intermittent Fasting(2), exercise daily, keep your carbohydrate intake to under 20 grams per day, and drinking a ton of water.  Entering ketosis can occur within about 2-7 days following the aforementioned strategy.  Once in ketosis, depending on your body and your activity level you can stay in ketosis while consuming from 20-50 grams of carbohydrates a day.  


If you want to talk through what you just read you can schedule a call with me by using this link: https://calendly.com/catalystjoe/15min or email me at [email protected]

Part Two: Experiences

My personal experience
I consider myself an athlete.  My weekly training consists of 4-6 days of Brazilian Jiu Jitsu (sometimes twice a day) and 1-3 times a week of strength training (a mix of kettlebells, barbells and bodyweight).  My diet has always been important to me, so that I can optimize my performance in and out of my training arenas. Endurance, power, strength and recovery usually dictated my daily nutrition.  I was worried that with the lack of glucose in my system I’d see a decrease in my performance.  I have not seen a decrease in my performance. With that in mind I have not been training for maximum strength or power.  Overall, my experience has been very positive on the Keto Diet.   My focus has been on maintaining my current strength level, increasing mobility, staying injury free and becoming better at Jiu Jitsu.  Below is a list of Pros and Cons that I have experienced (these are not listed in any particular order). 


  • Increased fat loss.  I went from just around 190lbs to 178.8lbs without increasing exercising or consciously adjusting my total calorie intake.  I have just been listening to my body after I break my morning fast (see: Intermittent Fasting for details on my morning diet regimen) and eating enough meals to keep me satiated.


  • Longer hunger satiation between meals.  I have noticed that I can go longer in between meals without getting extremely ‘hangry’ (think Snickers commercial where an angry biker eats a bar and turns back into a sweet old grandma because she is no longer hungry).


  • Decreased food cravings throughout the day.  I have been considered by many to be a croissant connoisseur.  Most mornings I craved a croissant, or chocolate ice cream at all times of day, but honestly those cravings are either gone or are so little I don’t even notice them.    


  • I become full during meals with a smaller portion of food.


  • Fewer energy crashes throughout the course of a day.  After a lot of meals, I used to feel lethargic-- I no longer notice this after my meals.  I also used to need a nap around 3:30-4pm, this is no longer the case. 


  • I was forced to cook more and cut out any to all processed/pre-packaged foods.  This is positive outcome no matter what diet you are using.


  • My sleep has been deeper and longer.  I feel more rested when I wake up each morning. 


  • Finally, the loss of body fat.  This one is not only evident by the scale, but also from the visible change in my body composition. 


  • Change in digestion.  During the initial week or so of my current keto adventure my stomach was not very happy.   I didn’t have pain or discomfort, but after eating a high fat meal I immediately had to use the bathroom.  Now that I am more “fat adapted” this is no longer the case.  But in the beginning, this was a con.  My body seems to really agree with this lifestyle while others may experience extreme digestion issues.


  • Grocery bill.  With the change in diet came an over haul of my pantry.  I had to obtain a lot of different foods and spices that I normally didn’t have stocked.  My initial two bills were double what they normally were.  I also found that quality high fat foods tend to be a higher in price than carbohydrate dense foods.  I don’t know why this is just what a comparison of my Stop & Shop receipts showed.  Now my bill seems to have evened out but there a less weeks of a less expensive receipt.


  • Difficultly eating out.  Going out to dinner can be difficult, but with a little ingenuity it is possible.  Most of the dishes won’t satisfy your macros as they are designed.  An example of something that could work while out is a cheese burger (extra cheese) with no bun, bacon, avocado, mayo on the side, and a small side salad with lots of olive oil on the side.  Don’t be afraid to ask for mayo or and butter on the side and add it to your protein. 


  • Constant meal prepping and or carrying of food.  To make sure that I have the right macro percentages covered I do have to spend a lot of time meal prepping or at least finding the right recipes to cook. 

If you want to talk through what you just read you can schedule a call with me by using this link: https://calendly.com/catalystjoe/15min or email me at [email protected]

**I’d like to note that during the majority of my experience with Keto I have been supplementing with exogenous (from outside the body) ketones


The experiences of Talia Mariani:  Catalyst Coach, Director of Catalyst Experience, and actor extraordinaire!
I came to Keto on a slightly different journey.  Diagnosed with Hashimoto’s (a hypothyroid, autoimmune condition) about 3 years ago, I felt as though I had already exhausted every anti-inflammatory protocol available.  I had heard about Keto through the various fitness channels, but having done Atkins all throughout high school, I wasn’t exactly eager to hop on another “low” to “no-carb” diet.  I admit, without giving it much thought, I chalked Keto up to just another nutritional fad.

 Then Mr. Joe Boffi began his Keto experiment.  Now, don’t tell him I said this, but he’s a rare bird in the fitness industry - he is someone whose knowledge and opinion I can easily trust.  So as he came skipping into work everyday, bragging about his increase of energy and lack of appetite or cravings, I began to see Keto, no longer as a simple fad-diet, but rather as a viable option worth exploring.

 Through living with Hashimoto’s over the past few years, I have learned to stop making fat or weight loss a goal – it simply proves too uncontrollable or disappointing.  Instead, my health and fitness goals are catered towards strength, keeping my body’s inflammatory responses low, and maintaining steady energy for daily workouts and life.  So as I began to research in order to prep for ketosis, while all the articles boasted about the diet’s benefits for fat loss and weight management, my attention was more so caught by claims such as “improved cognitive function,” “better digestion,” and “less inflammation.”

 Was it all too good to be true?  There was only one way to find out.  Here is a summary of my experience so far…



  • Butter and Bacon.  Enjoy!


  • Side effects from Hashimoto's improved (including eczema, bloating, dry skin, etc.)


  • Better sleep


  • I started sleeping better and my energy sustained throughout the entire day. 


  • Mental clouds parted and I could think and focus clearer than I had in years. 


  • My digestion became so regimented that I honestly started to brag about it in public spaces


  • The final, unexpected win?  The number on my scale adjusted in the right direction for the first time in 2 years.



  • The “Keto-Flu,” as all the blogs call it, is when your body works through its final glycogen stores and instead begins processing ketones for energy.  It can be quite the shocker for a system that’s become so reliant on glucose.  For me, the Keto-Flu took me down on day 6 for nearly 16 hours. The process was miserable.  I felt sick, lightheaded, and nauseous.  Truthfully, I consider myself lucky that the accompanying migraine forced me to sleep through most of it.  I’m not telling you all of this to scare you away from trying ketosis, but I do feel the experience is worth noting.  I’d hate for the Keto-Flu to take anyone by surprise.


  • It's a bit topsy turvy to start prioritizing fat in your meals.  It takes some practice and careful meal planning at first to get the hang of it.  Also, be prepared for some friends and family to give you some concerned looks while ordering out - it's okay, they'll be asking you for more information when they start to see the results ;)


  • Can’t forget becoming a living furnace / sweat monster!

Feel free to email Talia at [email protected] if you have any questions about her experiences!


Part 3: Conclusions

So, what’s the hype?
A lot of the chatter has to do with fat loss and ketones.  Without getting into the science of it, essentially during nutritional ketosis (keto diet) your body has no extra glucose to use, so your body starts to burn fat and make fatty acids.  Your liver then starts to produce ketones, from these fatty acids, instead of glucose for energy(3).  There are reports that ketones also improve mitochondria health, improved mental focus for some, and help to retard some diseases (like cancer(4)). Thus, a lot of the hype is about fat loss and the therapeutic effects ketones may have on the body.    


There is a common misconception that the Keto Diet (KD), or even ketosis is only about starvation.  While a person can reach ketosis through starvation, ultimately KD, or ketosis in general, is about the depletion and absence of glucose, and the presence of ketones to be utilized as an energy source.  Basically, the KD is an extremely low carb, moderate protein, and high fat diet.  During KD a person can still consume a large quantity of calories and not be starving themselves.  With all the different nutritional options out there, some options work really well for some and not so well for others.   If you are interested in KD give it a shot and see how you feel.  Quoting the amazing Dr. Dooley “As always, It’s your call!”   

Thank you for reading,

Joe Boffi
Co-Founder Catalyst S.P.O.R.T.
[email protected]

P.S. I hope you found some interesting information in this article and you are now better equipped to give KD a try if that is what you are looking for. Don't be afraid to contact me with questions or more information on how Catalyst can enhance your health & fitness!

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