Research done by Ray Peat points in another direction. His research shows not only that unsaturated fats are non-essential to humans but also toxic. On the contrary, he claims that saturated fats are healthy. You can find more information at his web site: http://raypeat.com/.
There are other researchers that claims that saturated fats and cholesterol are healthy. More information is available via the web site The International Network of Cholesterol Skeptics (THINCS): http://www.thincs.org/.
Future posts will go into greater detail.