Researchers, reporting last month in Circulation, have found that the amount of trans-fatty acids present in red blood cells correlates with the risk for subsequent heart attacks and death from coronary artery disease.
Investigators from Harvard Medical School studied blood samples from over 32,000 women participating in the Nurse's Health Study. They found that women who had high levels of trans-fats in their red blood cells also had high levels of LDL cholesterol ("bad" cholesterol) and low levels of HDL cholesterol ("good" cholesterol). The subsequent risk of heart attacks or cardiac death was over three times higher than expected in women with the highest trans-fat levels.
This elevated risk is greater than would be predicted from the elevations in LDL and reduction in HDL levels (an effect known to be associated with diets high in trans-fat), strongly suggesting that the trans-fatty acids themselves must directly increase cardiac risk.
This study is the first to directly measure trans-fat levels in the blood and correlate those levels with cardiac risk. All other studies that have indicted trans-fatty acids have relied on dietary histories alone to estimate the consumption of foods high in trans-fatty acids. Accordingly, this study will give strong ammunition to those campaigning to eliminate trans-fatty acids from American diets.
DrRich comments:
Any argument that trans-fatty acids are actually safe - an argument pleasing to the processed food industry - has been dealt a serious blow by this new study. Trans-fats really should be avoided.
Unfortunately, it is trans-fatty acids that allow us to enjoy processed foods that require long shelf-lives without liquefying or spoiling. So what's the healthy thing to do? Avoid processed foods as much as possible, and go for the fresh stuff whenever you can - at least until medical science figures out whether newer man-made fats (such as interesterified fats ) also produce premature degenerative diseases. You may not like caving in to the food nannies in this way, but you'll stand a better chance of living to fight another day.
Sources:
Sun Q, Ma J, Campos H, et al. A prospective study of trans fatty acids in erythrocytes and risk of coronary heart disease. Circulation March 2007; DOI: 10.1161/CIRCULATIONAHA.106.679985.
