In Finland we don't that much like all-you-can-eat type places. Mostly younger people go to them, and young couples who like to eat to satisfy their sexual needs. And those ice hockey players. In suburbs it's more famous, though there are two RAX in central Helsinki.
But there's one legendary all-you-can-eat place, called RAX. There they have all kinds of unhealthy food: pizza, chicken wings, pasta, salad, soup, sausages, french fries, lasagna. All you feel like eating when you are having a hung over, but after you eat you realize it was a huge mistake and feel shittier than you felt before putting anything in your mouth.
But as you don't need much mathematic, the food served there are not that nutritious plus they can include what ever, especially lot's of salt and super fat cheese. Also if you just choose to eat salad buffet, it's filled with super thick cucumber slices and can food. Yummy.
Here you can see the nutritious levels of food served in RAX.
with additional 1€ you get all-you-can-eat ice cream
Salad buffet: 5.95€
note: sometimes they have discount weeks, all-you-can-eat for 6.95€.