It's just that there have been one too many threads of people promoting some particular fad diet idea (gluten is poison! sugar is poison! soylent is the food of the future!) and I'm getting kind of sick of them. I've been hearing these fad diet ideas for years, it's just different things which are claimed to be the poison or different combinations of things or combination of restrictions which are claimed to be the be-all cure.
This thread hasn't been particularly bad, though you were a bit overly pushy about ketogenic diets and dismissive of criticisms of them earlier: "I'm not aware of any scientic data that found adverse consequences. You get a lot of resistace from health professionals because for the last decades what you eat on a ketogenic diet has been blamed for heart diseases or high cholesterol, but there never was scientific evidence to back up those claims."
> So eating above one's caloric requirement and a lack of energy are always problems of willpower?
No, there is not always a problem of lack of willpower. Metabolism plays a role, though diet and behavior play a big role too. There are certain circumstances for which ketogenic diets are appropriate, just like there are certain circumstances for which gluten free diets are appropriate; likewise, just because they are appropriate and effective in certain cases doesn't mean they are appropriate or effective for every case.
I think that for a lot of people, however, the problem is willpower. There are a lot of people who just want an easy excuse or an easy answer, when there really is an easy answer that just takes a bit more willpower.
I do believe that the low-carb, paleo, ketogenic, and likewise diet fads have at least helped combat the harmful emphasis on low-fat above all else. I recall at the height of the low-fat craze finding lots of fat free and low-fat foods that were stuffed with tons of sugar to compensate.
> I think everybody can get behind this, it's like thinking of the children.
No, I don't think everyone can get behind it. There are a lot of people who take the "you can eat whatever you want as long as it's not carbs" idea and eat way too much bacon, pork rinds, and the like.
Fresh fruits and vegetables are healthy. Eating pork rinds instead of a banana because the banana is fairly carb rich and the pork rinds are not is not healthy.
> So grains healthy, fat bad? As you don't mention meat that's probably also bad? Well, it's the details that get interesting, what are healthy foods.
I don't think dividing it into "this entire category of food is healthy, this food is not" is a good way to approach your diet. So no, I'm not claiming "grains healthy, fat bad". Both grains and fats are good for you, in moderation. Likewise meat. All of these things can be bad for you when taken to excess; eating too much meat can give you cancer (and some meats are fattier, leading to the problems with too much fat), too much fat can raise your cholesterol leading to heart disease, too much grains (especially highly refined grains) can lead to spikes in blood glucose and harm your insulin response.
What I'm saying is favor fruits and vegetables over grains, favor whole grains over refined, treat meat as a supplement, flavoring, or occasional treat rather than the central part of every meal, favor unsaturated fats (generally vegetable oils and fish) over saturated fats (generally from other animal sources), and keep refined sugar consumption very low. If you need to lose weight, eat a little less, and try to fill up a little more on things without much caloric value like greens (but don't go spending all of your time eating salads, as they generally come with dressings that consist mostly of fat and sugar, defeating the whole point).
Personally, I follow this by eating meat (of any form, fish, poultry or red meat) only about 3 times a week. I never drink soda (can't stand the stuff now that I'm not used to it any more). I generally use unsalted nuts or fruit as a snack if I need something to tide me over between meals (but don't snack often). I usually buy whole grain bread. But I cook with butter plenty (as well as with olive oil, I love sauteing food in a combination of the two), I put cream in my coffee, I enjoy the occasional juicy steak, I eat a lot of cheese (my one main vice), and I have the occasional dessert.
Now, I don't claim that my diet would work for everyone. That's why I'm not out selling it; it's just what happens to work for me. But I do think that it's good to employ an approach of moderation and avoiding thinking about food in black and white terms, unless there's a very good reason why a food should be completely banned (like if you have celiac disease, a nut allergy, or a moral objection to consuming animals).