Hydrogenated oils are created when hydrogen is added to unsaturated vegetable oils in order to increase their shelf life. In the 1960´s, scientific research was overwhelmingly demonstrating dangerous thecardiovascular and health risks of saturated fats derived from animals. In response to this research, attempts were made to substitute unsaturated vegetable oils with the dangerous saturated fats. However, unsaturated vegetable oil has a very short shelf-life and foods created using it spoil rapidly.
Scientists then discovered that by partially hydrogenating the unsaturated oils, the shelf life could be lengthened of food made from the result partially hydrogenated vegetable oil. From there, it took over 20 years until it was determined that partially hydrogenated vegetable oil is just as dangerous to cardiovascular health as the saturated oils found in animals. So the food industry has basically come full circle, and is back to adding a type of oil to most processed food that is dangerous to the cardiovascular health of the individual.
Hydrogenated oils and saturated fats are extremely harmful to cardiovascular health because in the environment found in the blood, these molecules tend to bind with each other and form plaques. Plaques are sticky and bind together and to the inside wall of blood arteries and veins and prevent blood flow.
A partial blockage of an artery will result in high blood pressure, both because the artery is required to transport the same amount of fluid in a smaller area, and also because the partially blocked artery is not nearly as elastic as a free artery. This narrowing of the arteries and increased blood pressure eventually will lead to the artery bursting under the pressure of blood flow. When this happens, tissue death results. This is very common in the arteries that supply blood to the heart and brain, resulting in a heart attack or stroke.
Because the health risks of hydrogenated are now well documented, movements are underway to eliminate the use of hydrogenated oils. The food industry, in general companies that make processed foods, are reluctant since the alternative oils are more expensive. The process of hydrogenating unsaturated fats is both easy and very cheap, and any change away from that will lead to increased costs for the processed foods industry. There does not yet exist an affordable substitute hydrogenated oils that are suitable for the processed food industry, however, there are many things individuals can do to reduce their intake of hydrogenated oils and trans fats.