Unripe, stale, and mouldy foods are unfit to be eaten and likely to cause severe illness.
3.

Foods are sometimes spoiled by having things mixed with them which are not food, or which are poisonous.
4.

The foods most liable to be adulterated in this way are milk, sugar, and butter.
5.

Tobacco, while not actually eaten, is thought by some persons to be a food, but it is not.

It is a poison, and injures all who use it.
6.