Skip to comments.Higher trans fat levels in blood associated with elevated risk of heart disease
Posted on 04/15/2007 11:28:09 AM PDT by neverdem
High consumption of trans fat, found mainly in partially hydrogenated vegetable oils and widely used by the food industry, has been linked to an increased risk of coronary heart disease (CHD). New York and Philadelphia have passed measures eliminating its use in restaurants, and other cities are considering similar bans. A new study from the Harvard School of Public Health (HSPH) provides the strongest association to date between trans fat and heart disease. It found that women in the U.S. with the highest levels of trans fat in their blood had three times the risk of CHD as those with the lowest levels.
The study was published online on March 26, 2007, and will appear in the April 10, 2007 print issue of Circulation: Journal of the American Heart Association.
"The strength of this study is that the amount of trans fatty acid levels was measured in blood samples from the study population. Because humans cannot synthesize trans fatty acids, the amount of trans fat in red blood cells is an excellent biomarker of trans fat intake," said senior author Frank Hu, associate professor of nutrition and epidemiology at HSPH.
Clinical trials have shown that trans fatty acids increase LDL cholesterol and lower HDL cholesterol, making them the only class of fatty acids, which includes saturated fat, to have this dual effect. HDL (high-density lipoprotein) is considered a "good" cholesterol; LDL (low-density lipoprotein) a "bad" cholesterol.
The researchers, led by Hu and lead author Qi Sun, a graduate research assistant at HSPH, set out to test the assumption that higher trans fatty acid levels in erythrocytesred blood cellswere associated with a higher risk of heart disease among U.S. women. Blood samples collected in 1989 and 1990 from 32,826 participants in the Brigham and Womens Hospital-based Nurses Health Study were examined. During six years of follow-up, 166 cases of CHD were diagnosed and matched with 327 controls for age, smoking status, fasting status and date of blood drawing.
After adjusting for age, smoking status and other dietary and lifestyle cardiovascular risk factors, the researchers found that a higher level of trans fatty acids in red blood cells was associated with an elevated risk of CHD. The risk among women in the top quartile of trans fat levels was triple that of the lowest quartile. "Positive associations have been shown in earlier studies based on dietary data provided by the participants, but the use of biomarkers of trans fatty acids is believed to be more reliable than self-reports. This is probably the reason why we see an even stronger association between blood levels of trans fat and risk of CHD in this study," said Sun.
"These data provide further justifications for current efforts to remove trans fat from foods and restaurant meals," said Hu. "Trans fat intake in the U.S. is still high. Reducing trans fat intake should remain an important public health priority."
Makes me want to run out to KFC tonight ;) ...we must remember why they use this type of fat in the first place- because of the lard/butter scares of the 1970s. But now real butter and real lards are OK now...funny, eh?
Uh-oh. Look for our new Democrat Congress and Senate to regulate all restaurants and their menus. NYC started a very dangerous precedent with the “no trans-fats” allowed dictate. After trans-fats it’ll be salt. Then beef. Then barstools without proper padding.
While correlation is not causation, thanks for the epidemiological biomarker link!
The LDL/Plaque link is well-established, and so is the very-low-LDL/Plaque-reduction-obstruction-lessening (LDL 30 or less for extended time).
I can think of no reason whatever (except ignorance and/or false bravado)for the general public to disregard the science that shows transfat transformation into obstructing artery plaque at a rate that greatly exceeds non-hydrogenated fats.
I noticed a comment upthread about “butter scare”......yeh, THAT was when transfats were introduced as “safer”....they sure as hell aren’t!
I specifically remember learning in my A&P class that ALL types of fats (including “good” fats) - will become trans-fats if they are heated at high enough temps. for long enough. So even if “good” fats are used in the deep fryers at fast-food restaurants etc. - if the oil isn’t changed after each use of the fryer - it becomes a trans-fat.
blinachka wrote: Specifically remember learning in my A&P class that ALL types of fats (including good fats) - will become trans-fats if they are heated at high enough temps. for long enough. So even if good fats are used in the deep fryers at fast-food restaurants etc. - if the oil isnt changed after each use of the fryer - it becomes a trans-fat.
I believe this too and this might be like the spinach-scares recently...it might be a simple problem of not preparing the food properly.
The hydrogenation process employs Quan quanquan
1. High heat
2. A metal catalyst such as nickel, zinc, copper, or other reactive metals
3. Hydrogen gas.
The metals are used to react with the hydrogen gas which is bubbled up through the mixture. The metals catalyze the hydrogen and carbon atoms and converts the fatty acids by flipping one of the attached hydrogen molecules and rotating it half the diameter of the carbon chain.
This effectively creates a new molecular shape resulting in a stiffer or more rigid material, hence the change from a liquid to a semi-solid or solid substance. This new shape stiffens with the hydrogenation process making the oil behave more like a saturated fat (such as coconut fat which is 92% saturation and solid at room temperature).
Trans fats are the result of this reaction.
Partial hydrogenation, or “brush hydrogenation” is a minimal conversion step which only offers a small degree of reaction by hydrogenation. Brush hydrogenation increases stability for volatile fatty acids like the omega 3 (alpha-linolenic) and omega 6 (linoleic) polyunsaturated oils. Most commercial salad dressing oils, such as soybean oil, have been brush hydrogenated.
Hydrogenation raises the melting point of the fat and retards rancidity. But as recent health studies have found other problems can ensue when consuming large amounts of trans fats from hydrogenated products.
Trans Fatty Acid
Trans fatty acids are synthetic saturated fats. They are generally man-made, however they can form naturally in cow’s milk with up to 14% butter fat, and can also occur in vegetable fats (through hydrogenation). The hydrogen molecules attached at the center of the fatty acid carbon chain flips 180 degrees, which straightens the natural curve or kink in the typical cis-configured fat.
When converted, the cis-shape chemically alters to a trans configuration and hence is called a trans fat. Most margarine and vegetable shortening have been trans fat converted through full or partial hydrogenation process. Trans fats interfere with metabolic absorption efficiencies and tend to congregate at adipose tissue sites. They are difficult to excrete from the body and are a low quality energy source.
They should ban living. It always leads to death.
LOL! As my cousin said (many years ago) at the tender age of 8: "Life is a terminal disease."!!
All the natural health food people have been warning about this for decades but noooooo, they weren’t *real* professional doctors with *real* degrees from *real* accredited universities, so what did they know?
LOL...what did they know? I wonder too. A lot of people probably don’t know this but vegetarians have a higher rate of heart disease because of a lack of certain proteins that are only found in red meats. Proving that there is a danger or risk to everything.