I have no stake in the Keto game; I neither love nor hate the diet. I’ve done it for a few months, which I think is crucial when critiquing any diet. It’s important to experience something yourself before recommending or discouraging someone else from using it, particularly as a nutritionist. There are aspects of the diet that I like and aspects that I dislike. Keto is by far the hottest weight loss diet right now, and naturally every diet will have its benefits and drawbacks.
Dieting is both very simple and very complex. You have to find the right method of restricting your calorie intake. While the idea of restricting calories is elementary, the follow through is what most people struggle with. They know what to do, they just can’t do it. What is the easiest way for you to control your calorie intake over a sustained period of time? Could it be Keto?
The number one reason most people experiment with the ketogenic diet is for weight loss. As we mentioned, the number one key to success with weight loss is the person’s ability to comply with the diet over a long period of time. The ketogenic diet is restrictive… but also not. Hear me out. The diet is restrictive in the sense that you are essentially eliminating an entire macronutrient group, carbohydrates. No more fruits, bread, pasta, starches, grains etc. In that regard the diet seems very restrictive. But you have to consider what happens when you consume carbohydrates. You get a surge of energy due to a spike in blood glucose levels, followed by a subsequent drop in said glucose. This leads to low energy, more hunger, and cravings for more carbs. Hard to stay on a diet when you’re feeling ‘hangry’ every three hours.
Since you are not ingesting carbohydrates on the ketogenic diet, your blood sugar remains stable all day every day. Hunger pangs become much less frequent, and you’ll often find yourself going hours without the thought of food entering your mind. This is a huge plus for any dieter.
However, achieving a caloric deficit is still vital. If there is any metabolic benefit to the ketogenic diet, it is minor. You cannot simply remove carbs, eat pepperoni and cheese all day, and expect to lose weight. You have to eat responsibly.
Brain Health/Disease Prevention
Many people report improvements in mental clarity on keto. The brain can use both glucose and ketones (the energy derived from fat metabolization) to function. These reports are largely anecdotal, as it would be difficult to measure differences in mental acuity from glucose vs. ketones since there are so many other variables involved. In addition, would it necessarily be the ketones providing the improved brain function or is it the stability in blood glucose?
Perhaps the greatest benefit of the ketogenic diet is its effect on neurodegenerative diseases. As mentioned before, the brain can use both glucose and ketones for energy. However, glucose is the preferred energy source. If glucose is available, the brain (and body in most cases) will use it. Many neurodegenerative diseases are based upon the brain’s inability to use glucose. By starving the body of glucose and consuming high amounts of fats, it allows ketones to become the main fuel source and gives the brain an alternate fuel to use.
This ideology applies to certain forms of cancer as well. Many cancer cells rely on glucose to thrive and grow. These same cells are unable to utilize ketones. Once again, starving the body of glucose and using ketones as its main energy source may be helpful in mitigating the effects of certain diseases. (Note: I am not a doctor, just telling you what I know).
Carbohydrates cause inflammation to some degree, largely based on the type and quality of carbohydrate. Inflammation has its place and function, but too much can lead to pain, disease, etc. Although I feel the gluten intolerance narrative is largely overblown, there are some people that truly have a hard time digesting gluten. The same applies to dairy. If you are a person with say, chronic joint pain, perhaps a low carb or keto diet can help alleviate the symptoms.
The body has multiple energy systems when it comes to exercise. The energy system you use is based on both the intensity and duration of the activity. Endurance athletes use mainly the slow glycolytic (carbohydrate fueled) and beta oxidative (fat fueled) energy systems. Carbohydrate storage has a limited capacity, eventually the body will turn to fats for fuel. Fats are a robust energy source, they can sustain activity for a very long time. Unfortunately, most people are so reliant on carbs that they have a hard time making the transition to fats when carbohydrate stores run low.
Ever heard of a runner getting his ‘second wind?’ This occurs when they have made the switch from carbs to fats. An aerobic athlete can forgo this period of fatigue if they are running on fats from the very beginning.
The Delicate State That is Ketosis
Your body wants to use carbs for energy. It’s dying to use carbs for energy. Carbs are truly the body’s preferred energy source. Anyone who has done the ketogenic diet for an extended period knows that it is not only hard to get into ketosis, it’s hard to stay in ketosis. The only way to truly know is to use a blood ketone meter, which I own. I can tell you from experience, blood ketone levels fluctuate all day every day, leaving you questioning what you’re doing wrong… or right. Point is, it can be a frustrating experience.
You may experience gut issues when making the transition from a carbohydrate-based diet to a fat-based diet. I’ll spare you the details, but you may become well acquainted with your lavatory.
The worst thing that can happen is being in what I call ‘no man’s land’, where you are consuming too many carbs to get into ketosis but not enough to fuel your day-to-day activity.
The Long Term Sustainability of Elimination Diets
Will you really be able to avoid cake, pizza, and ice cream for the rest of your life? Better yet, should you? The body wants to achieve homeostasis and thus will adjust to anything you do (within reason). If you avoid carbs for a long period you will lose the ability to tolerate carbs. You will produce less of the digestive enzymes to break down carbs. This is why I suggest cycling off of keto every few months and slowly re-introduce carbs back into your diet, just for a week or so.
Anaerobic Sport Performance
Earlier we touched on the keto diet’s application to endurance sports. We mentioned how endurance athletes utilize both carbs and fats during exercise. This is not the case for all sports. Anaerobic sports like football, sprinting, hockey, and mixed martial arts among others primarily utilize creatine and carbohydrates for energy. Rarely will the athlete utilize fats unless they are completely depleted. Even then, the beta oxidative system that utilizes fats will not be able to keep up with the high speed nature of the sport and thus the athlete’s performance will suffer greatly.
Included in these anaerobic sports is bodybuilding. If you are a gym rat looking to put on as much muscle as possible, then the keto diet is just not optimal. I’m not saying it’s impossible to add muscle, that would be an irresponsible statement. However, the lack of carbs will negatively impact anabolism and performance in the gym. The glycolytic energy system is a major component of bodybuilding.
Making the Mental Shift
This is rarely discussed but in my opinion is the biggest barrier to success with the ketogenic diet. We have been brought up in a world that heavily markets low fat or fat free foods, dressings, desserts, and meals. When you are bombarded with this for your entire life, it becomes hard to accept anything else as true.
I know fats are important for many aspects of overall health and wellness. Hell, I know saturated fats are important. But I must admit, it was hard to make the mental shift and accept the fact that I have to eat upwards of 200g of fat per day in order to get into a state of ketosis. All too often I have people come up to me asking for advice on keto and in almost every situation they are eating too much protein and/or not enough fat. They experience the ‘no man’s land’ state that I alluded to earlier.
Keto is MOST appropriate for:
- Sedentary people looking to lose weight and improve their health
- People who may be predisposed to certain diseases
- Endurance athletes
Keto may not be ideal for:
- Anaerobic athletes or people looking to gain maximal amounts of muscle
- People who live a lifestyle in which they cannot consistently consume meals that allow them maintain a state of ketosis.