Bacon's primary asset is its fat, and that fat— surprise! – is primarily monounsaturated. Fifty percent of the fat in bacon is monounsaturated, mostly consisting of oleic acid, the type so valued in olive oil. About three percent of that is palmitoleic acid, a monounsaturate with valuable antimicrobial properties. About 40 percent of bacon fat is saturated, a level that worries fat phobics, but is the reason why bacon fat is relatively stable and unlikely to go rancid under normal storage and cooking conditions. That's important, given the fact that the remaining 10 percent is in the valuable but unstable form of polyunsaturates.7
Pork fat also contains a novel form of phosphatidylcholine that possesses antioxidant activity superior to Vitamin E. This may be one reason why lard and bacon fat are relatively stable and not prone to rancidity from free radicals.8
Bacon fat from pastured pigs also comes replete with fat-soluble vitamin D, provided it's bacon from foraging pigs that romp outdoors in the sun for most of year. Factory-farmed pigs kept indoors and fed rations from soy, casein, corn meal, and other grains, are likely to show low levels of Vitamin D.