This is including eating out for lunch on weekdays though, which costs at least 10 dollars a day.

Fruit and vegetables are more expensive. A decent apple will cost about 1.50 each. 1 metric litre of milk costs about 2 dollars, and 10 eggs wil probably run you around 3 dollars.

Meat, depending on the origin and cut, can cost you about 6 dollars for about 150 grams (or a much, much more).

You can get frozen manufactured food for fairly reasonable prices, but I'm kind of a snob and pretty much will not eat anything that has ingredients I don't understand in it.