The fats good for human health belong to the category of polyunsaturated fatty acids, specifically to the category of Omega-3s and Omega-6s. Within these two categories are the essential fatty acids that humans must consume in food to keep themselves healthy, as the body is unable to synthesize them on its own.
There are two essential fatty acids: alpha-linolenic acid, an Omega-3, and the linolenic acid belonging to the group of omega-6s. These two essential fatty acids, also known as vitamin F can be found in plant oils like linseed and seeds. The correct ratio between Omega-3s and Omega-6s in the diet should be 1 to 5. Currently the average is 1 to 10.
There are other healthy fats belonging to the long-chain Omega-3s, with a chemical composition of a chain of 20 or more carbon atoms, which are found primarily in fish oil, also rich in vitamin A and D. They are fatty acids composed from the essential fatty acids, and the ones especially important to the body are eicosapentaenoic acid, or EPA, and docosahexaenoic acid, or DHA, found mostly in fish and fish products.
Finally there is a particular type of Omega-6, CLA (conjugated linoleic acid), whose primary source is milk and dairy products, particularly from grazing animals, and which can also be found to a lesser extent in beef, veal, pork, lamb and chicken. CLA has beneficial effects for the immune system, the cardiovascular system, bone health and the glycemic index. It is good to integrate it into the diet in the right quantities and as part of a balanced diet.
A diet rich in polyunsaturated fatty acids is associated with a reduced risk of thrombotic infarct and cardiovascular diseases in general, as they reduce excessive cholesterol and triglycerides and their accumulation in the arteries.
Polyunsaturated fats are also indispensable for the production of energy, the formation of cellular membranes, the transfer of oxygen from air to the blood, hemoglobin synthesis, proper hormonal balance and hormonal production, vasoconstriction and the regulation of pain and inflammation.
They are anticarcinogenic, improve microcirculation and mitigate damage caused by arthritis.