The chemical structure of the fat that you eat is more important than you think. Everyone needs some fat in their diet, but too much and too much of the wrong types of fat can be bad for your health. A Dutch group of researchers has recently reported that trans fat (more correctly trans fatty acids) are more detrimental to cardiovascular health than saturated fats.
Generally speaking, polyunsaturated fats like those found in most vegetable oils and monounsaturated fats that are found in olive and canola oil are considered good fats to have in the diet. Saturated fats, most abundant in animal products such as meat and milk, are usually considered bad, but recent evidence suggests that trans fatty acids are worse.
Trans fatty acids do occur in milk naturally, but are more commonly produced during food processing. However, because we eat so much processed food now, in countries like the United States and the Netherlands, trans fat can make up to 7% of our total fat intake.
Avoiding trans fats may be difficult for the average consumer because the amount of trans fat in foods is not identified on their labels. It is included however in the total fat reported. The French fries, fried chicken, and doughnuts from fast food outlets all contain high levels of trans fat. Since the manufacturing process of hydrogenation is primarily responsible for the creation of trans fats, avoid anything containing hydrogenated oils.
Other reported effects of trans fatty acids that may be detrimental to health:
- Increases blood insulin levels in humans in response to glucose load
- Affects immune response
- Decreases the response of the red blood cell to insulin
- Inhibits the function of membrane-related enzymes
- Causes alterations in physiological properties of biological membranes
- Causes alterations in adipose cell size, cell number, lipid class, and fatty acid composition