Earlier quoted context omitted.
> It’s so hard to eat healthy, I honestly cannot fathom how people do it. Learn to cook well so that eating out would result in lower quality meals compared to what you could make yourself. Once you're controlling what goes into your meals, instead of outsourcing it, that makes it easier to control portion sizes, how much fat/oils go into things (I've found that restaurant dishes have an absurd amount of fat in them…
“Has a high amount of fat” isn’t the same thing as “unhealthy”. “Has a high amount of calories” isn’t either. Wanting to lose weight isn’t necessarily about health, and eating a lot of fat is an effective way to lose weight.
However the fats used in restaurants are often used for frying, and likely have been used repeatedly for many hours. Oils used for frying can quickly produce compounds that are not great to consume, like various aldehydes, VOCs, free radicals etc[1]. If they've been used for hours, the chances of those compounds being in your food are high.
They are often low quality, as well, like soybean oils that can be high in fats that can be unhealthy in excess and might contribute to CVD.
I bring up the fat thing not because I think fats are the reason why people gain weight, I'm well aware of how high fat low carb diets are effective. I bring it up because restaurants often put fats into food you might not put it in at home, and the food can soak a lot of it up, turning what might be a 500 calorie dish into something that's 1200 calories or more. If you're trying to watch what you eat, eating out can make that hard because you don't know exactly how much food you're actually eating, and you can't really rely on nutritional breakdowns you might find online or from the establishments themselves.
The foods the fats are in also seem to be high in carbohydrates, which isn't great for ketosis.
I also bring it up because of Ulillillia's decision to degrease the pizzas that were the only thing he ate. By doing that he was able to lose weight while literally only eating pizza for every meal for years.