Cottonseed oil, extracted from cotton seeds, is used in some margarines and in commercially made salad dressing. The ancient Chinese used the oil as a medicine and a lamp oil.
Until the middle of the 19th century when cottonseed oil production began, so much cotton seed was left over from cotton production, that it was considered a health problem.
Cottonseed and cottonseed meal are used in feed for livestock, dairy cattle, and poultry. Cottonseed oil is also used for food products such as margarine and salad dressing.