If you google the ketogenic diet, a lot of interesting options come up. Articles written by ".com doctors" selling products, posts by "health-influencer" Instagramm-ers, and other alleged health authorities. But what is a ketogenic diet? And is it a good idea?
According to the trendy diet world, the ketogenic diet is a carbohydrate-restricted, high-fat diet, that is promoted on the basis of "turning your body into a fat burning machine." But let's back up for a minute—what is a ketogenic diet, really, and is it a good idea?
In short, the diet industry has (as they have with many things), deeply over-simplified a complicated biological process and tried to re-brand it into a trendy selling point.
Keto diet blogs tell readers to eat a very high-fat and low-carbohydrate diet, basically restricting their intake to things like meats, eggs, oils, certain nuts and seeds, and non-starchy vegetables, like greens.
It's a bit like the Paleo diet, but more carbohydrate restrictive. A look into the science of the state of ketosis is slightly less glamorous than what is depicted on keto-blogs. Ketosis is a metabolic state that your body enters when it does not have enough glucose to use for energy.
Basically, your brain and body are starving, but you must continue to feed your brain to stay alive, so you begin to use fat stores to create ketone bodies in the liver, which are transported to the blood for fuel.
Importantly, ketone bodies are acidic, and while your body is equipped with many systems to try to maintain a viable blood pH, if you have too many ketone bodies in your blood for too long, you can overwhelm your body's buffing system, which can lead to blood acidosis.
Acidosis can lead to icky symptoms such as confusion, fatigue, headache, lack of appetite, increased heart rate, a drop in blood pressure, and rapid and shallow breathing.
While it's true that your brain makes very efficient use of ketone bodies, this efficiency is a survival mechanism because your body is essentially clinging to any form of fuel it can receive.
It is the human body's line of defense before beginning to metabolize muscles as fuel, which is something that those who use the ketogenic diet to "get in shape," should consider before entering ketosis.
There have been reports of intentionally advising patients to enter a state of ketosis as an intervention for epilepsy and diabetes. Remember that these are extreme dietary interventions for extreme conditions.
Your brain's preferred source of fuel is glucose (carbs), so for a normal, healthy person, I would suggest feeding it what it prefers.
Ketogenic diets require extremely low levels of carbohydrate consumption, which is unrealistic and unsustainable in the long-term, and I personally would not suggest them as a path to health.
Rather, I would suggest eating a balanced, sustainable diet that makes your both brain and body feel energized and happy.