The ketogenic diet a.k.a keto has often been promoted as a magic bullet for fat loss and overall health. Fortunes have been built on the promise of keto being THE answer that people are looking for to improve body composition and make gains. On the fat loss front we know that although not superior to a diet rich in carbohydrates, keto may be a solid option. But is keto a good idea for muscle growth or a potential gains killer?
What did they test? The authors reviewed the current available literature to see the effect of the ketogenic diet on muscle hypertrophy in resistance trained individuals.
What did they find? Overall, there were no differences between the keto groups and the control groups but keto did not seem to promote favorable increases in muscle mass.
What does it mean for you? This study comes with a few limitations that are discussed in detail below but if you absolutely love keto, being in a calorie surplus will ensure that you’re gaining muscle mass. If you don’t really like keto and want to maximize muscle growth, it’s best that you consume a diet rich in carbohydrates.
What’s the Problem?
Ah, the ketogenic diet (or “keto” for short). A diet that you’ve probably heard of, no matter if you’re a fitness enthusiast or not. A diet based on prioritizing fat and protein intake while reducing the macronutrient responsible for literally everything bad in the world, from obesity to the stock market of 1987. A diet that drastically reduces….*dramatic music intensifies* CARBOHYDRATES *screams of shock*.
Just kidding, carbohydrates are far from being a “bad” macronutrient, regardless of whether you’re training or not and they’re not the “cause of obesity” as many claim. Some of the main arguments made against carbs are mostly based on the carbohydrate insulin-model (CIM) of obesity, a model that proposes insulin as the main driver of obesity, something that has been disproven multiple times by the scientific community 1 2. We also came out with a great article on “why sugar did not cause the obesity epidemic”, which I think is worth checking out 3.
“But wait a second Dr. Pak”, I hear you saying, “I thought I was reading about ketogenic diets and muscle gain, not another “carbs are fine for you” article”. That’s true, good reader, I just needed to throw some carb™ disclaimers and set the scene for this research review. Now, enough hypothetical conversations, let’s look at the “problem” in question.
Keto diets reduce carbohydrates to approximately less than 50g per day or around 10% or less of one's total energy and require fat and protein intake to be prioritized 4. The keto diet is mostly known as a “fat/weight loss diet”, probably due to its supposed superiority compared to “regular diets”, something that has not been reflected in the literature comparing diets following keto-like macronutrient compositions versus “regular” diets that include carbohydrates 5. That said, the keto diet has been shown to be beneficial for inducing improvements in certain pathologies, like epilepsy, and regardless of not being superior to a “regular” diet, may also help improve body composition in different populations 6 7. The majority of research on the keto diet is also around obesity and whether the reduction of carbohydrates can aid in improving body composition in obese individuals but not much research has been carried out on muscle growth in trained individuals, and more specifically, people who lift.
Aside from keto not being “the one magic trick” for losing fat, many people seem to enjoy eating more fat and protein, often due to being able to eat more of certain foods that they like (eg: fatty cuts of meat, dairy etc). And that’s totally fine,*hippie voice on* namaste, you do you, but what about the gains brooo?
Is keto a viable option for those who want to increase muscle mass? Can you have your keto cake and eat it too? This systematic review by Vargas-Molina et al may shed light on these questions!