Trans Fats in Foods
Metabolism of natural 20-carbon polyunsaturated fatty acids like arachidonic acid results in the biosynthesis of mediators with potent physiological effects such as prostaglandins, prostacyclins, thromboxanes, leukotrienes, and lipoxins. These substances are known collectively as eicosanoids because they contain 20 carbon atoms (Greek eikosi = 20). However, polyunsaturated trans fatty acids cannot be used to produce useful mediators because the molecules have unnatural shapes that are not recognized by enzymes such as cyclooxygenase and lipoxygenase. Although low levels of trans-vaccenic acid occur naturally in some animal food products, partially hydrogenated oils contain a large proportion of diverse trans fatty acids. Trans fatty acids that are incorporated into the cell membranes create denser membranes that alter the normal functions of the cell.
Effect of trans fats on the heart.
Dietary trans fats raise the level of low-density lipoproteins (LDL or "bad lipoproteins") increasing the risk of coronary heart disease. Trans fats also reduce high-density lipoproteins (HDL or "good lipoproteins"), and raise levels of triglycerides in the blood. Both of these conditions are associated with insulin resistance which is linked to diabetes, hypertension, and cardiovascular disease.
Researchers have reported that people who ate partially hydrogenated oils, which are high in Trans fats, worsened their blood lipid profiles and had nearly twice the risk of heart attacks compared with those who did not consume hydrogenated oils. Because of the overwhelming scientific evidence linking trans fats to cardiovascular diseases, the Food and Drug Administration started requiring all food labels to disclose the amount of trans fat per serving in 2006.
Effect of trans fats on the brain.
Trans fats also have a detrimental effect on the brain and nervous system. Neural tissue consists mainly of lipids and fats. Myelin, the protective sheath that covers communicating neurons, is composed of 30% protein and 70% fat. Oleic acid and DHA are two of the principal fatty acids in myelin. Studies show that trans fatty acids in the diet get incorporated into brain cell membranes, including the myelin sheath that insulates neurons.[10] These synthetic fats replace the natural DHA in the membrane, which affects the electrical activity of the neuron.
Trans fatty acid molecules alter the ability of neurons to communicate and may cause neural degeneration and diminished mental performance. Neurodegenerative disorders such as multiple sclerosis (MS), Parkinson's Disease, and Alzheimer's Disease appear to exhibit membrane loss of fatty acids.
Unfortunately, our ingestion of trans fatty acids starts in infancy. A Canadian study showed that an average of 7.2% of the total fatty acids of human breast milk consisted of trans fatty acids which originated from the consumption by the mothers of partially hydrogenated vegetable oils. Baby milk formulas have violated rules and exceeded the amount of trans fats allowed. Baby milk formulas are thus a source of trans fats in babies.
Source: http://www.scientificpsychic.com/fitness/fattyacids2.html
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