Are Vegetable Oils Really Healthier Than Animal Fats?

Industrially processed vegetable (seed) oils are ubiquitous in the supermarket. These bright gold-yellow oils are often sold in large plastic bottles and include canola, cottonseed, corn, safflower, and soybean oil just to name a few. Part of the reason these oils are found everywhere is that they can be used in nearly any application including baking, deep-frying, sautéing, and are usually one of the first ingredients in that salad dressing in your fridge. Just about any processed food nowadays has some combination of soybean or palm oil.

These oils were meant to replace animal fats and improve the health of America when they were introduced during the second half of the 20th century. The benefits were obvious. Consuming vegetable oil instead of animal fat was the best way to reduce blood cholesterol levels, which was at the time, understood to be a major cause of heart disease. However, even decades later, obesity and chronic disease rates continue to rise. In fact, the introduction of industrial vegetable oils to the food supply correlates very well with the rise in obesity rates. So my question is: Was introducing these oils to the food supply a good idea and should we be consuming them? To understand the exact implication of the introduction of vegetable oils, we have to go back to the very beginning when they were introduced and examine what has happened since.

The vegetable oil takeover started with Crisco

The origin of plant-based fats in the western diet actually goes back to 1911 with the introduction of Crisco (crystallized cottonseed oil). Crisco, or shortening, was introduced by Procter & Gamble in 1911 as part of the early industrialized food boom. Crisco is made by hydrogenation of cottonseed oil, a process which removes some of the carbon-carbon double bonds in the oil, giving it properties more like animal fats, which are solid at room temperature.

The use of “solid plant fats” like Crisco caused serious problems for Americans that we are now quite aware of and trying to fix. The primary problem lies in the hydrogenation process used to make these fats. Hydrogenation causes the chemical structure of the fatty acids to slightly rearrange, creating trans-fatty acids. These types of fats are not found in nature…