Food is a non-countable noun when it means food in general (less food not fewer food); we don’t say one food or two foods. It is both singular and plural depending on the context of the statement, so foods is acceptable. (Many snack foods aren’t good for your health). We also use ‘foods’ when talk about varieties or types of food (foods like sandwiches, crisps and fruit):
Nobody can survive for long without food.
Why have you put so much food in your plate? Can you eat all this!
Her mother-in-law kept on talking with food in her mouth.
Those refugees in camps are running out of food.
This supermarket sells all varieties of foods from Chinese and Indian suppliers.
Many of these foods require refrigeration.
Here you can buy all foreign foods at reasonable prices and they’re unbeatable.
As she has just recovered after a long illness, the doctor said she needs to eat fruits, vegetables, and other healthy foods.
His mother is allergic to certain foods; she can’t eat dairy, soy and a lot of other things!
He looked in the freezer and found all kinds of frozen foods, so he took everything he could lay his hands on.
Some of my favourite Italian foods are Panzenella, Bruschetta and Focaccia Bread.
