Edible oils of vegetable origin come from a number of vegetable growths: olives, corn, nuts (as almond, peanut), seeds (as sunflower, poppy), and cotton. Olive-oil has long been used in the countries of olive-culture. The other vegetable oils are of relatively recent development as factors in the usual human diet. With the exception of olive-oil and such fats as are inherent constituents of most foods, fats as human food have been taken from animal foods, such as milk and pork.

Olive-oil and most animal fats are considered more generally digestible by all persons than the other oils that have more recently come into food-use. This is ascribed by many to their more wonted or agreeable flavor. The other oils now prepared as foods are sometimes by-products of processes that serve humanity in other ways. Cottonseed-oil is a notable illustration of this. The more extended use of nuts as a substantial food has led to a new valuation of their fats and a marked and rapid development of their use in made foods also as substitutes for animal-fat foods, as peanut-butter for butter made from milk. These are not full diet-equivalents of the animal fats whose place in the diet they share.

Fat In Human Foods (Compare Percentages)

Olive-oil is the most highly valued of salad-oils. It is also the most expensive. This leads to its adulteration or mixture with other oils. It needs to be kept pure for human use.