The No Nonsense Ketogenic Article of Your Dreams

The No-Nonsense Ketogenic Article of Your Dreams
The ketogenic diet is probably the trendiest diet ever. It’s also probably the most misunderstood diet ever as marketers and influencers love to take advantage of its popularity by overexaggerating claims and taking science out of context to hype up ketogenic products.                                                                                                    Ultimately, you’re wondering, is keto truly good or bad for you? Is it overrated or can it be useful? Let’s answer this looking at the unbiased science, shall we? 

 What is Keto? (pronounced key-toe not ket-toe)
So, what even is keto? The ketogenic diet is essentially a moderate protein, high fat, and very low carb diet. The goal of this diet is to toss you into a state called ketosis by severely restricting carbohydrate intake.
This carbohydrate limit for keto is generally about 50 grams a day (2,3). This is not a set in the stone limit for everybody as mild ketosis has been seen in some people with slightly higher intakes, but generally speaking, you’d want to stay under about 20-60g of carbs daily to remain in ketosis. This likely means the only carbs you can eat are fibrous vegetables.
What the Heck is Ketosis?
So being on a ketogenic diet puts you into ketosis. Ketosis is where your body’s primary fuel source of glucose and fat switches to primarily using fat and ketones (4,6).
Your brain, in particular, uses primarily glucose. It can’t use fat so when carbs are severely restricted on keto, your brain switches to using ketone bodies that your body produces. Ketone bodies also called ketones are essentially an alternative fuel source for your brain when glucose isn’t available and despite what keto zealots will tell you, ketones are likely not the ideal fuel source for your brain when compared to glucose (9,10).
As for the rest of your body, it begins to utilize fat more as opposed to glucose (carbs). This might negatively affect you depending on your goal, but we’ll talk more about that later.
This entire process of converting to ketosis generally takes about 3-4 days and usually isn’t pleasant to adapt to (5). This is why people often report what they describe as keto fog or keto flu within the first few days/weeks attempting the diet describing symptoms of sickness or fatigue (16).
While on keto, it’s also common for people to report bad breaths known as keto breath because of the presence of ketone bodies in the blood (6).
A bit random, but it’s interesting to note that ketosis can also occur with extended fasting and times of starvation (11).
How Keto Started
Even though your annoying co-workers on keto might make this diet sound new and flashy, it’s actually not new. The ketogenic diet has been frolicking around for an entire century and if you’ve been attentive, it spikes in popularity every couple of years, then dies down slightly before spiking up again.
And this might be shocking, but keto actually didn’t start as some flashy fat melting diet popularized by celebrities. It actually started way back in the 1920s where doctors used it to treat epilepsy (1).
Epilepsy is a neurological disorder associated with seizures. 1 in 26 people will develop epilepsy and fortunately, the ketogenic diet has been shown to help.
What About My Love Handles Bro?
You’re probably thinking, “that’s great and all that keto helps children with seizures, but what about my weight loss goals bro? Is keto good for that?”
Yes, keto can definitely be good for weight loss, but it isn’t magical or superior to other diets as keto marketers would have you to think.
When people first learn about ketosis, many misunderstandings arise.
Because you do burn more fat than carbs while in ketosis, it leads many to believe you’ll lose more fat on keto.
Unfortunately, what marketers don’t want you to know is that burning and losing fat are completely different. You can burn more fat, but not necessarily lose more fat off your body.
How is this so?
Well, your body adapts to the fuel source you provide it. With extreme fat intakes and extreme carb restrictions, your body is obviously going to burn more fat and fewer carbs because that’s what you’re providing it (8,12).
Burning fat simply means your body is oxidizing it as fuel. On the other hand, to lose fat, you have to burn more total fat than you store or in other words, you have to be in a caloric deficit.
When tightly controlled studies comparing low carb vs low-fat diets, even though the low carb group burned more fat, it also stored more fat making the net outcome the same when calories and protein intake are equal (7).
This is why despite the hype behind ketosis, fat loss is not superior on a ketogenic diet given calories and protein in a diet is matched.
Net energy balance (calories in vs calories out) still determines fat loss, not ketosis (14). This is also to a good time to bring up that the ketogenic diet shares the same awful potential as every other diet on this planet which is, it still has the potential to make you fat.
Even though ketosis might sound great, it doesn’t miraculously save you from excess calorie consumption. If you eat more calories than your body can burn over time, you will still gain fat regardless if you’re in ketosis or not.
Why the Ketogenic Diet Might Be a Good Idea For Fat Loss
Even though the ketogenic diet isn’t necessarily superior when compared with other diets given the same calories, there are two advantages to the ketogenic diet you might want to consider if the goal is fat loss.
The first advantage is appetite suppression. Ketosis can suppress appetite for some people if maintained consistently (13).
Now, this appetite suppression benefit generally takes about 3 weeks to take effect, so like any other diet, to reap the benefits, you have to be consistent (15).
The second advantage of the ketogenic diet is early weight loss (7). This applies to all low carb type of diet as restricting carbs causes additional losses in water and glycogen at the beginning. However, studies show long term body composition is the same.
Even though the long-term effects are the same, in my experience, the early weight loss of a low carb diet like keto can be very beneficial for clients who want to see the scale drop fast early on.
This could ignite motivation in people who are easily discouraged when initial progress appears too slow even if most of the early weight is just water.
Why the Ketogenic Diet Might Be a Bad Idea For Fat Loss
Despite being a viable weight loss diet on paper, people forget in practice, you have to actually stick to the diet consistently to reap the rewards.
Some of the studies I mentioned earlier are metabolic ward studies or tightly controlled studies, meaning participants were housed and forced to eat the exact food instructed. This is great to study the effects of a diet with clarity, but this doesn’t tell us much about whether the diet is easy to stick to given your own free will.
When you look at ketogenic studies where participants weren’t paid, housed, and forced to eat specific foods, it showed the ketogenic diet is not easy to adhere to (17).
This is very similar to people I know who claim to be doing keto. Most people I see who do keto can’t restrict carbs consistently and end up having cheat meals on the weekends which inevitably will kick you out of ketosis. Even if you ate no carbs the following week, it would take you half the week to finally get into ketosis in which you would stay for only a couple of days before cheating again.
A true keto diet has very little to no carbs which are usually too restrictive for people to stick to for long periods. Research has shown us the only people who actually stick to it consistently are paid athletes and people housed in confined studies like lab rats.
Still, the ketogenic diet can be a great weight loss diet if you can stick to it consistently. If you can’t, no sweat, there are plenty of other options that are just as good. Keto is simply just another tool to choose from in the endless toolbox of diets.
What About Other Goals?
Even though the ketogenic diet started gaining mainstream popularity for the sake of weight loss, many influencers are promoting it for other goals like hypertrophy or performance.
In reality, a ketogenic diet seems to be potentially suboptimal for both hypertrophy and performance.
Let’s take a deeper look at these aspects.
Keto and Athletic Performance
When it comes to traditional sports performance, keto isn’t ideal both in terms of aerobic and anaerobic measures.
This is because, with a ketogenic diet, you lack carbohydrates and besides tasting really good, carbohydrates have other crucial benefits (28).
For starters, when carbs are burned for fuel, they produce more energy than fat (18). On top of this, a carb sufficient diet will allow the glycogen in your muscles to be full along with replenishing it during exercise, both of which are critical for maximum performance (19).
Here’s a systematic review in 2016 showing carbs are beneficial for performance particularly when exercising for longer than 90 minutes (20).
In actual competition, victories are attained thanks to carbohydrates. Race winning moves, sports of long durations, and bouts of high intensity all rely heavily on carbs (21,22,23,24,27).
Research has also indicated in concurrent training where both resistance and endurances styles of training occur, a ketogenic diet is not optimal (19).
This study on CrossFit, for example, concluded that a moderately low carb diet might be ok for short durations of CrossFit, but a higher carb diet is likely needed to maximize performance especially for longer demands (25).
As far as pure anaerobic performance, this study showed keto isn’t as good either (26). You’ll likely lose power.
Further Considerations for Athletic Performance on Keto
Another big thing to consider as it pertains to athletic performance is metabolic flexibility. This is a concept made famous by Dr. Mike T Nelson and it’s basically the idea of how flexible your metabolism is. If you’re in ketosis, your metabolism isn’t very flexible as it’s only adapted to fat and not carbs.
Having a flexible metabolism means you can switch back and forth between fat and carb use instead of just solely using one.
By going on keto, you’re less metabolically flexible. As carbs are restricted, an enzyme called PDH which controls carbohydrate use gets hindered (29).
Once this enzyme is hindered, it doesn’t recover immediately. When you reintroduce carbs, you still won’t maximize the performance benefits of carbohydrates for some time even if glycogen stores are replenished (29).
With all this considered, at best keto is ok for athletic performance and at worse it’s vastly inferior to any other diet that includes sufficient carbs.
Keto and Lifting Performance
But surprisingly outside of traditional athletic sports and concurrent styles of training, the evidence behind keto’s effect on pure lifting is not as clear cut.
Most keto studies on strength training have major limitations like not controlling for equal protein as well as not testing for blood ketones to ensure ketosis is achieved and maintained.
Considering the glaring limitations, some studies do show the ketogenic diet can maintain strength comparable to the control groups (30,31).
This review article on carb’s effect on resistance training concluded it most likely depends on the volume, duration, and intensity (32). With more volume/time of lifting, carbohydrates become increasingly important.
This lines up well with a study done on intermediate Olympic lifters, a sport in which volume and duration of intensity are fairly low compared to traditional sports (33). The Olympic lifters lost fat and muscle on a ketogenic diet but were able to maintain performance. While Olympic weightlifting is considerably different than the strength training most people do to get jacked, this study at least shows the ketogenic diet can be advantageous for weight class restricted athletes looking to maintain performance.
So what’s the verdict on keto’s effect on strength training?
Considering the data we do have on traditional athletic performance and the limited data we have on keto’s direct relationship with strength training, my conclusion is that a ketogenic diet is a likely fine for lifting performance given volume and duration is low.
However, I do think a higher carbohydrate diet would be beneficial for maximizing strength training if your workouts involve a lot of sets/reps or go pass 1 hour.
Keto and Muscle Building
Some people will say you can’t build much muscle on keto because you can’t eat much protein without going out of ketosis.
In theory, this is true because protein can be converted into glucose which would stop ketosis, but when played out in practice, high protein intakes have been shown to not kick people out of ketosis as long as carb intake is very low (34).
Research has shown as much as 2.8g of protein per kg of body weight doesn’t withdraw you from ketosis. That’s way more than enough daily protein to build muscle.
As for not having sufficient carbs, we know that the muscle signaling enzyme mTOR is unaffected by carbohydrate restriction (35).
So then this begs the question if a protein is equal, is there any muscle-building benefit or drawback to eating a ketogenic diet?
The answer is yes. This infamous study done by Vargas and colleagues shows that despite being assigned a caloric surplus, the ketogenic group could not eat in a surplus and resulted in no muscle growth.
This is not saying you can’t build muscle on a ketogenic diet, but it does show that it’s difficult to eat enough total calories on keto. This is likely because the ketogenic diet as discussed earlier is pretty good at suppressing your appetite.
In general, I don’t recommend the ketogenic for muscle building. While it is possible, it’s not optimal because it makes it harder to eat sufficient calories and overall gym performance is likely compromised (32).
Bonus Study
I have one more ketogenic study that’s important to highlight (36). This one compared a ketogenic diet with just a basic low carb diet.
We know if calories are matched, the weight loss will be the same, but what I found interesting is that the low carb diet outperformed the ketogenic diet when it came to micronutrients.
With the ketogenic diet’s drastically low carb requirements, you miss out on fruits, starches, and grains, all of which have plenty of valuable vitamins and minerals.
It goes to show you two important things.
  • If you prefer a low carb diet, a simple low carb diet is probably better than a pure ketogenic diet where carbs are practically banned.
  • If you do choose to do a ketogenic diet, selecting nutrient-dense foods is important to prevent nutrient deficiencies given your limited food choices.
Wrapping it All Up
I hate to sound like I’m bragging, but this is literally as comprehensive and unbiased of a ketogenic diet article as you’re going to get. Just like with all my other articles, I’ll be updating it if new evidence comes out.
To recap everything into adorable little bullet points, here are the key takeaways.
  • The ketogenic diet’s goal is to put you into the state of ketosis. This generally takes 3-4 days of heavy carb restriction.
  • Most people are not able to stay in ketosis because of dieting inconsistencies, not to mention there are annoying side effects to adapting to ketosis.
  • Regardless of attaining ketosis or not, the ketogenic diet is like every other diet when calories and protein are matched. It can make you lose weight if you eat low enough calories and it can make you gain weight if you eat too many.
  • The ketogenic diet can be a viable fat loss diet especially considering its appetite-suppressing effects, but only if you can stick to it consistently which the research has shown to be hard to do given your own free will.
  • The ketogenic diet is subpar for athletic and typical sports performance.
  • The ketogenic diet is fine for traditional weight lifting, but likely not optimal if your workouts are long or involve high volume.
  • The ketogenic diet can build muscle but is likely not optimal for hypertrophy as it’s hard to eat sufficient calories paired with the fact that lifting performance might be compromised.
  • If you’re not careful, the ketogenic diet may leave you deficient in micronutrients as food choice is severely limited.
References
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