Peanuts are also very widely sold for garden bird feeding. Low grade or culled peanuts not suitable for the edible market are used in the production of peanut oil, seed and feed, although some owners of pet hookbills avoid these kinds for that reason. Peanuts have a variety of industrial end uses. Paint, varnish, lubricating oil, leather dressings, furniture polish, insecticides, and nitroglycerin are made from peanut oil. Soap is made from saponified oil, and many cosmetics contain peanut oil and its derivatives. The protein portion of the oil is used in the manufacture of some textile fibers. Peanut oil is a mainly monounsaturated fat, much of which is oleic acid, the healthful type of fat that has been implicated for skin health. Some say peanuts are an unbalanced source of fat because they have only trace amounts of required Omega-3 fats.Some brands of peanut butter are fortified with Omega-3 in the form of flaxseed oil to balance the ratio of Omega-3 to Omega-6.