Har skrevet ett langt svar nå. 
Oh. My. God! You should read a bit about low carb high fat (LCHF) before discrediting it.
And learn the difference between ketosis (safe and controlled) and ketoacidosis (diabetes out of control). Ketosis is safe – the blood sugar will not get dangerously low (dizziness and stuff). In ketosis, the dizziness and out-of-energy feeling is temporary and only last the first day or two as the body is switching to a much more reliable source of energy – fat. I’ve been in ketosis for months and I’ve gained muscles, lost body fat, my blood sugar is constant at a good level and my doctor tells me that my blood samples are better (i.e. I’m healthier). I don’t get cravings, I just get hungry. And I feel SUPER!
“Essential” is a word we put in front of carbs, fat and proteins to show that it’s a substance that we absolutely need to include in our diet since the body is not able to produce this substance by itself. As of yet, no one has discovered an essential carbohydrate. But we know of several essential fatty acids (fat) and several essential amino acids (protein). So what does this tell us? We do not need to eat carbohydrates AT ALL – unless you’re a body builder. I have heard of people doing Vasaloppet (90 km on skis) without carbs.
“3. Eat ENOUGH carbohydrates to obtain optimal brain functionality”:
I agree on this one, sort of, because “enough carbs” is actually ZERO. All the carbs the body needs can be made from fat or protein. And the body does NOT go into starvation as long as you eat a lot of fat.
According to your logic, if I drink a lot of gasoline, I will gain weight? :P The body is more complex than “calorie in, calorie out”. If you eat very low carb and high fat and adequate protein, the body will burn more calories by itself (by making the ketones and stuff). I can eat 3000 calories a day, not exercise and still lose fat (and keep the muscles I already have).
OK, it takes a while for the body to learn to rely on fat instead of glucose, but if you hang in there and keep trying, you’ll learn that the body works FAR BETTER on fat than glucose. We can keep going for a really, really long time, because the body has the energy it needs. So NO, your work-out will not suffer (again, as long as you’re not a body builder) as you DO have readily energy to keep you going.
And this IS a “normal diet”. I’m eating natural food, and food that we’re adapted to eating. Humans have been around for about 200.000 years. We’ve been farmers for 5-10.000 years – depending on where you’re from. In Northern Europe, we’ve been farmers for merely 5.000 years. What did we eat prior to the agricultural revolution? We ate a lot of meat and a few vegetables and fruits that we happened to find. We haven’t evolved that much in such a short period. The body still isn’t adapted to eating high carb.
But it’s important to note that the less carbs you eat, the more fat you need to eat. I agree that starvation is not healthy. But the body does not starve if you eat a lot a fat, adequate protein and no carb. On such diet (I’ll eat like this for the rest of my life BTW) we learn that we shouldn’t eat unless we’re hungry, and we should eat until we’re comfortably full. As long as you listen to your body and give it the energy it needs, it will NOT go into starvation mode.
I see you got one part right that a lot of people don’t know: eating lots of carbs over a long period results in insulin resistance for many people – and eventually diabetes type 2. Congratulation, just by acknowledging that you’re leaning towards low carb. 
It’s fascinating that tribes eating LCHF (there are a few African tribes, and the Inuit used to be LCHF) do not have such sicknesses… By the way, the Inuit now do (now that we’ve introduced them to HCLF), along with heart problems, obesity and a bunch of other sicknesses.
And please find evidence for stating that saturated fat is unhealthy. There is none. It’s just something that everyone “knows”. Like when everyone “knew” that the world was flat…
Do you think that losing weight (fat) when you’re overweight is unhealthy? When burning fat, the fat is released from the fat cells and is circulating in our veins prior to being used as fuel by the cells. And how does the body store the fat? As SATURATED FAT! So we have saturated fat circulating in our veins when burning fat.
Keys lipid hypothesis is wrong on both accounts:
1. Saturated fat does not increase your cholesterol
2. Cholesterol does not clog your arteries
Most doctors still measure total cholesterol and prescribe statins for people with high total cholesterol. The same doctors acknowledge that there’s good cholesterol and bad cholesterol. So if the total cholesterol is high, but the bad cholesterol is low, shouldn’t that be a good thing? Total cholesterol doesn’t tell us a damn thing. And what’s the “bad cholesterol”? Carbohydrates stored in our body…
By eating eggs and bacon for breakfast every day (and sometimes for lunch and dinner too), and eating sauces made of crème and spices (nothing else) for three months, I became more healthy:
Total cholesterol went from 5,5 (a bit “high”) to 5,2 (still a bit “high”)
Triglycerides (very bad cholesterol) went from 1,6 (which isn’t that bad) to 0,7 (which is excellent).
HDL (good cholesterol) went from 1,1 (a bit low) to 1,2 (still a bit low, but increased by 0,1)
LDL (both good and bad cholesterol, the smallest ones are bad, the bigger ones are good. But the triglycerides gives us an indication how many of them are good and how many of them are bad): I don’t know since there was something wrong with the last sample.
By depriving the body of fat (including saturated fat), you’re depriving the heart and a lot of other organs of energy. I don’t understand how that should be healthy…
But I agree that not all fats are healthy. Keep away from trans fat! So use butter! Not “oh my god, I can’t believe it’s not butter” butter and margarine, but DAIRY BUTTER. Trans fat is damaged fat and causes cancer. The only oils/fats that should be used for frying is dairy butter and extra virgin coconut oil. Extra virgin olive oil is healthy, but do not heat as it will generate trans fat.
And protein is a horrible source of energy. That’s not why we need it. It’s a building stone.
Funny you should mention effects on your hormones and neglecting to mention that insulin IS a hormone – an anabolic hormone. By eating high carb over a longer period, the insulin level is generally too high. The body needs to have a hormonal balance, so it tries to reduce the production of other anabolic hormones to keep the balance. What are the other anabolic hormones, you ask? Growth hormone and sex hormones (testosterone and oestrogen). Do we really want that? In addition, the insulin is our fat storing hormone…
I don’t really know why I bothered, but I’m really passionate about this subject.