No doubt you've heard that trans fats are bad for you and that you should avoid foods containing them. But why exactly are they so awful, and how do trans fats increase your risk of cardiovascular disease?
What is a Trans Fat?
First, a little science. Trans fat is just the common name for unsaturated fat with trans-isomer fatty acids. Trans fats are created through a process called partial hydrogenation. Why use this process if it creates an unhealthy product? Well, trans fats make oils more solid and extend their shelf life, as well as producing a pleasing texture in foods. Trans fats are found mainly in commerically baked cookies, cakes, crackers and some breads. Many restaurants use trans fats as frying oils as well, calling them liquid shortening.
How Do Trans Fats Affect You?
Trans fats may increase baked goods' shelf life, but they shorten yours! Trans fats raise your LDL ("bad" cholesterol) level and lowers your HDL ("good" cholesterol) level. Trans fats cause these negative cholesterol changes at twice the rate caused by simple saturated fats, which are unhealthy enough on their own.
Trans fats also raise your levels of C-reactive protein (CRP). A recent study showed that participants with the highest trans fat consumption level had CRP levels 73% higher than those who consumed the least trans fats.
Since the LDL/HDL cholesterol ratio and the CRP level are the two blood tests most often used to measure one's risk of cardiovascular disease, you can see that trans fats are bad news to anyone wanting to reduce their risk of cardiovascular disease (that would be everyone!).
What Do Studies Show?
The major study on the effect of trans fats on individuals was done in 2006. Among its findings:
- On a per-calorie basis, trans fats apparently increase the risk of coronary heart disease more than any other macronutrient. In fact, they contribute to a
substantially increased risk at even low levels of consumption.
- In a test of 140,000 subjects, a 2% increase in caloric intake from trans fats was associated with a 23% increase in coronary heart disease incidence.
- It is estimated that 30,000 - 100,000 cardiac deaths in the United States each year can be attrituted to trans fat consumption.
Where Are Trans Fats Found?
We've established that trans fats are bad for your cardiovascular health. Experts recommend that you eat no trans fats at all, or at least limit your intake to 1 or 2 grams daily. Be careful even of products boasting "0 grams of trans fat!," because this doesn't necessarily mean that the product has no trans fat - it simply has 0 grams per serving. Products can make this claim by making a serving just small enough to reach the 1 g threshold for reporting trans fat.
If you see the words "partially hydrogenated" in the ingredients, move on.
Educating yourself about trans fats and their negative affect on heart health is an important step in becoming healthier!