Eddy, the angry low carb diabetic blogger, has already ranted about this. Eddy is not keto however. He just dislikes anything that doesn’t exult low carb. The link between keto and starvation is important. TAC also notes that the brain runs on glucose, but low carb high fat (LCHF) followers are adamant that this is not the case.
I spent a few years studying biochemistry, and most of that time was spent learning about human metabolism. In the main we would look at what happens when systems are not working in order to understand the many complex processes at play when they are functioning properly, and for this reason the metabolic changes that occur in starvation were always a topic of interest. Because of this I have always had a strange fascination with ketosis, a metabolic state that occurs during starvation, and a great example of the stunning adaptability and resourcefulness of the human body.
Keto is very easy to be knocked out of, because it is not the body's natural state. The body and brain prefer glucose as fuel.
One of the really interesting things about ketosis is that it has a definite switching mechanism. Unlike a lot of biological systems which operate by degrees, it is either on or off in the human body, and as it is a starvation response, it is not considered an ideal state to be in. Ketosis is very much an emergency strategy, turned on during severe food shortage. Our bodies are never that keen to go into it, and will rapidly switch back to normal glucose metabolism once adequate nutritional intake is resumed.
The comments are as expected, as those who've lost weight eating less while skipping carbs descend to tout their success. This topic has taken on a special urgency because I now have a friend in real life (female) who seems to be trying the ketogenic diet to lose some weight. The only carbs she consumes regularly come from beer.
There is however another way to push the body into ketosis without being subjected to the severe starvation that normally accompanies it. A diet that is extremely high in fat, very low in carbohydrates, and fairly low in protein can induce a state of ketosis without a huge restriction in calories. The reasons why ketosis can be induced in this way are not well understood, but it seems likely that it is little more than a strange anomaly in the way ketosis is triggered, and that the body is being tricked into thinking it is being starved due to a very low carbohydrate and protein intake. The extremes of the ketogenic diet are something that we would have been unlikely to have encountered in any natural environment during our evolutionary history, so this non-starvation ketosis state is most likely due to a tiny flaw in our metabolic programming.
This can be applied to more than just keto touts and scammers:
In researching, I spoke to literally dozens of people, both researchers and clinicians, including world leading experts who have conducted some of the most important research into its effects (the very research that allowed its inclusion in the NICE guidelines as a treatment for epilepsy). I spoke to dietitians who have spent years working with the diet, putting hundreds of patients through it and dedicating their lives to its use. I also have Captain Science, who I would wager knows more about food, health and evidence based practice than all of the low carb commenters put together. Everyone I spoke to agreed, even fund raising organisations that are huge advocates of the ketogenic diet as a medical treatment. This is a medical intervention that pushes your body into an extreme state, and there are grave dangers associated with its unregulated use.
There’s a lot of rant and little evidence in this particular entry, beginning with a lengthy response to the critics of the first piece, which did include evidence and quotations from scholars in the field.
Desperation is where the vultures of pseudoscience gather, quick to pour on shame and scorn, and then offer salvation with their universal cures. It is a deception as old as the hills, and a remind that although ancient bloodletting and Victorian potions are ancient history, their poisonous legacy lives on in a new breed of dietary quacks.