Well I know personally I have switched to a "keto" diet, and continue to stay on it not due to weight loss but just the amazing concentration levels and feeling I get while on it.

You are limited to essentially 20g of carbs a day total. This is enough to get a healthy dose of vegetables (not fruit of any kind - leafy greens) and that is about it. Maybe a dollup of sriracha.

Either way, after being on the diet for a couple months I had one bite of a chocolate bar and let me tell you, the flavor was 1000x more intense and I felt no need for more after the first bite.

Of course this is one person's experience, YMMV.

People go on low carbohydrate or ketogenic diets and feel better because cortisol and adrenaline levels are boosted. It's like getting a cortisone shot. This affect can last a year or two. But then eventually stress hormone resistance develops and the whole thing falls apart with some ugly health consequences. People get crashed testosterone and thyroid levels and brain fog.

Sustained low carb is a bad idea. You are mimicking the metabolism of starvation. For the most part you want to be operating with glycogen topped up.

>You are mimicking the metabolism of starvation

Really? Because I feel a heck of a lot less hungry, and sometimes need to remind myself that it's past time to eat breakfast or lunch.

I should have been clearer. I was specifically referring to simple carbohydrates (glucose, fructose etc) and avoiding all and for a period of 8 weeks I consumed no fruit. During that time I consumed the main bulk of my diet consisted of legumes and vegetables. All meals were prepared and cooked by either myself or my wife.

We did consume rye bread, but that was made ourselves and used only the amount of sugar needed to activate the yeast.

After 8 weeks I have returned fruit into my diet, but always whole.

The point I was trying to make on the root comment in this, was that simply going cold turkey on sugar, in my case, wasn't hassle free because of the headaches, but it was worth it.

right. if parent is talking about switching to a ketogenic diet (hardly any carbs), feeling bad for a few weeks is entirely normal as your brain switches over to ketones for fuel. and your fluid / sodium levels adjust (one needs higher sodium intake during transition). and if parent cut out gluten, that has been reported to have opiate-like withdrawl symptoms as well.

sources: the art and science of low carb living, wheat belly