Keto. Ketosis. A Ketogenic Diet. As these phrases are currently the #1 searched health and fitness related subjects on google right now, you’ve probably heard the buzz and have wondered what it’s all about! Just like you many of you may have, I hopped on the keto bandwagon earlier this year... with mixed results. Let’s chat a little bit about what keto is, what it does to your body, how to get into ketosis, and who it may or may not be suited for!
Ketosis is a metabolic state where the body produces “ketones” and burns these ketones and fat for fuel as opposed to carbohydrates. Ketogenic diets are characterized by a consistently high fat, moderate protein, and very low carbohydrate consumption. Typically, carbohydrates are the body's most readily available and preferred fuel source for fast energy. After you consume carbohydrates, be it a can of soda, a banana, or a sweet potato, those carbs are broken down into glucose and released/absorbed into your bloodstream through the small intestines at varying speeds. Depending on how quickly the food is digested (simple vs. complex carbohydrates), the pancreas will secrete varying amounts of insulin to prevent blood glucose levels from rising too high. This insulin spike causes blood sugar levels to fall and for those of us who are more insulin-resistant, subsequently leads to those familiar “Carb Coma”-like symptoms such as fatigue, lack of focus / energy, and mental fog.
When the body doesn’t have access to glucose for an extended period of time (through fasting, low-carb diets, or prolonged exercise), the body will burn stored fats instead of glucose, eventually resulting in a buildup of ketones from the breakdown of fatty acids, which may then be used as fuel. As it turns out, fatty acids and ketones are the brain’s preferred fuel source. This explains why so many people report the feeling of having a clean energy burn in addition to increased mental clarity and focus as one of the many positive benefits of being in a ketogenic state (aka the opposite of being in a 24/7 carb coma). By avoiding the vast majority of carbohydrates, moderating protein intake, and eating lots of fat to slow digestion, the body doesn’t produce a large insulin spike which leads to another one of the main benefits of a ketogenic diet - helping to reset and increase your body’s sensitivity to insulin and thus your body’s ability to more efficiently handle insulin spikes and use carbohydrates as fuel in the future. Being in a ketogenic state also means that your body has gotten incredibly efficient at burning fat as fuel… not only the fat that you eat, but also the fat that all of us tend to store on our bodys and work our tails off to try to get rid of!
Here is something important to note - there is a BIG difference between eating a high-fat / low-carb diet and ACTUALLY being in ketosis where your body is burning ketones for fuel instead of carbs. How do you know you’re in ketosis? Breath and pee sticks aren’t nearly as accurate as a blood glucose monitor… after a finger prick, you’ll want to see your BHB (Beta-Hydroxybutyrate) levels consistently ABOVE 0.5mm, without the use of supplements like exogenous ketones to help get you there. Especially in Western cultures, most people are extremely dependent upon carbs for fuel. We can’t help it, it’s just how we grew up! Even if you eat SUPER clean, you’re probably eating considerably more carbs than you will be able to eat if you decide the ketogenic diet is right for you. Herein lies one of my major qualms with keto - it is often extremely difficult to get into a state of ketosis, both physically, mentally, and from a practical standpoint. Most people can take anywhere from 2-3 days all the way up to TWO OR MORE WEEKS to transition from burning carbs for fuel to producing and burning enough ketones to officially be in ketosis. Any slip up in diet may result in an insulin spike which would halt the production of ketones, effectively “kicking you out” of ketosis or prolonging the time it takes to get INTO ketosis. Many people experience flu-like symptoms during this timeframe as your body makes this difficult adjustment, including nausea, fatigue, dizziness, irritability, etc… not fun at all. I personally experienced Keto Flu HARD for 3 days when I made the transition to ketosis and I only stayed in ketosis for about 3 weeks. Why? As awesome as the benefits of being in ketosis may be once you get finally there, ketosis is super hard to get into, even more difficult to maintain, and definitely isn’t for everyone!
Every single body is different and we are all predisposed to handle foods differently. Everyone’s endocrine systems operate a little differently as well and we all have varying levels of hormones such as estrogen, testosterone, cortisol, growth hormone, and insulin. Most people see positive results pretty quickly from cutting carbohydrate consumption overall but in the long term, men and especially women need a certain amount of carbohydrates for optimal reproductive hormone function and ketosis can have a negative effect on those functions. If you lead a high-stress life or are prone to adrenal fatigue, keto may not be right for you. In addition, if you play soccer, go to crossfit, do HIIT workouts, or are AT ALL interested in athletic performance I would HIGHLY recommend against ketosis. If your heart rate rises above a certain threshold, your body stops being able to metabolize fat for fuel and HAS to turn to glycogen stored in the muscle cells and the liver. Basically, if you’re doing any form of exercise that is going to cause you to get out of breath for more than a couple of minutes, you’re going to need to be burning glycogen for fuel and the only way to replenish your glycogen stores is to eat carbohydrates. While I lost close to 10 pounds and leaned out in the three weeks I was in ketosis, my athletic performance ability drastically reduced and my workouts REALLY suffered.
Again, everyone is different. For folks who are looking for increased mental clarity, more sustained energy, and would like to lose some fat but aren’t too concerned about how they’re performing in the gym or on the field, ketosis may be a great fit! It also may be a great fit for most people for a couple of weeks per year as a way to reset insulin sensitivity and help your body more efficiently burn both carbohydrates and fats when you get out of ketosis. Overall, I often recommend ketosis for many of my weight-loss clients but hardly any of my performance clients or clients with high-stress lifestyles or pre-existing metabolic conditions. The important thing, as always, is to do your research, ask your doctor, listen to your body, and perhaps try it yourself to see how you respond.