The mechanism at the end of the day is still caloric restriction that leads to weight loss. Keto is just a means to that end.
E.g. insulin levels affects digestion, food high in sugars stimulates insulin secretion, which in turn leads to more fat being stored.
Foods made of refined carbohydrates can give you diabetes and yes, you can eat more calories on a Keto diet, versus a high carbs diet. I know because I tried both, with strict measurements and daily notes.
That said, I don’t think keto diets are healthy. Our body is made to eat vegetables. And we need carbs and sugars too — except that when they come from fruits and vegetables, you also get fibers, which diminishes insulin secretion, plus you get needed nutrients not found in white bread or cheesecake, so again, we’re talking of calories that aren’t equal.
1) A ketogenic diet is wasteful by nature, you excrete some percent of the calories you consume.
2) It completely ignores the effects of hormones. You need insulin to store fat and build muscle. A diet that triggers more insulin may result in storing more fat. This does not violate the first law of thermodynamics - this energy will either be burned from your fat stores, or compensated for by reducing your metabolism. I expect in reality a combination of both.
Nutritionists have promoted so many falsehoods based on faulty studies, forever damaging the image of the healthcare industry, that people now feel justified in ignoring sound medical advice and embracing alt-truth (e.g. anti-vaxers).
But I understand that mentality. I see myself as a very logical person compared to the general population, yet when my doctor tells me I need to lower my cholesterol, I ignore her. What does she know? What they taught her in Medical school, and I don't trust that at all. She doesn't have the time in our rushed 10 minute appointments to debate me on the subject, or even give me a recommended reading list.
I feel the need to do my own research on the subject by reading medical papers but I haven't had the energy or inclination yet. From what I have bumped into over the years, it seems your basic HDL and LDL numbers don't say much about risk of heart disease or stroke.
If it is swapped with a mix of protein and carbs, then you have some confounding variables of the thermic effect of the protein to account for.
From what I have seen, keto diets work due to two things: 1) Reduced caloric intake due to chopping out carbs - a major swath of foods 2) Increased adherence due to stabilizing blood sugar levels and thereby increasing satiety (the whole "stay full longer" thing)
If you have other studies that have been shown significant in an isocaloric state, I'd love to see them. I just haven't run across any that have shown good control around these areas. I personally like keto (and bacon) so I'm always looking for another excuse to do it, but I don't think that there is a ton of evidence for it doing any hormonal magic in healthy populations at the moment.
That's like saying that calling `fsync` will make your files bigger because it promotes data storage. It might store some data earlier, but the end balance is the same.
So keto may reduce your weight, but it's not actually reducing your fat stores, it's just reducing the amount of water in your body.
I saw one good description of what is going on: You don't ever lose fat cells just the amount of fat each one stores. When you enter ketosis your cells give up some of the water they were using as place holders for the fat they are waiting to store. Thus the periodic "whoosh" that ketorers report. Every few weeks you notice you have to pee a lot and you lose a few pounds.