Trans-fatty acids effects

Mozaffarian D. Trans fatty acids—effects on systemic inflammation and endothelial function. Atheroscler. 2006 7 29-32. 

Judd, J.T., Clevidence, B.A., Muesing, R.A., Wittes, J., Sunkin, M.E. and Podczasy, J. (1994) Dietary trans fatty acids Effects on plasma lipids and lipoproteins of healthy men and women. Am. J. Clin. Nutr., 59, 861-868. 

Kritchevsky, D. (1982). Trans fatty acid effects in experimental atherosclerosis. Journal of Federation Proceeding, 41(11), 2813-7. 

Small amounts of trans-unsamrated fatty acids are found in ruminant fat (eg, butter fat has 2-7%), where they arise from the action of microorganisms in the rumen, but the main source in the human diet is from partially hydrogenated vegetable oils (eg, margarine). Trans fatty acids compete with essential fatty acids and may exacerbate essential fatty acid deficiency. Moreover, they are strucmrally similar to samrated fatty acids (Chapter 14) and have comparable effects in the promotion of hypercholesterolemia and atherosclerosis (Chapter 26). 

Figure 13.15 The effect of diet on the Cl 8 1 trans fatty acids in the lipids of human milk (a) diet rich in cows milk fat, (b) diet rich in hydrogenated vegetable oil. (Courtesy of A. Stolyhwo.)...

Ascherio, A. and Willett, W. (1997). Health effects of trans fatty acids. Am. J. Clin. Nutr. 66, 1006S-1010S. 

CN165 Svahn, ]. G., F. Feldl, N. C. Raiha, B. Koletzko, and I. E. Axelsson. Different quantities and quality of fat in milk products given to young children effects on long chain polyunsaturated fatty acids and trans fatty acids in plasma. Acta Paediatr 2002 91(1) 20-29. 

When trans-fatty acids are fed to rats with adequate amounts of essential fatty acids, they have little effect on growth, longevity, or reproduction, but when fed as the sole source of lipids they exaggerate the symptoms of essential fatty acid deficiency (111). An effect on the metabolism of long chain polyunsaturated fatty acids was noted however. 

The TRANSFACT study was a randomized, controlled, crossover study (n = 46), investigating the effects of industrially compared to natural trans-fatty acids (11-12 g/day, representing about 5% of daily energy). The study showed that trans-fatty acids from industrially produced sources resulted in lower plasma HDL-cholesterol concentrations... 

The reductionist approach of isolating dairy product components including calcium, CLA, and trans-fatty acids in dietary interventions trials often yields inconclusive results. It is therefore highly plausible that dairy products exert maximum health benefits when consumed in their natural form. Because individuals do not generally consume these individual dairy components in isolation, examining the effects of these foods in their whole forms should be encouraged. 

Chardigny, J. M., Destaillats, F., Malpuech-Brugere, C., Moulin, J., Bauman, D. E., Lock, A. L., Barbano, D. M., Mensink, R. P., Bezelgues, J. B., Chaumont, P., Combe, N., Cristiani, I., et al. (2008). Do trans fatty acids from industrially produced sources and from natural sources have the same effect on cardiovascular disease risk factors in healthy subjects Results of the trans Fatty Acids Collaboration (TRANSFACT) study. Am. ]. Clin. Nutr. 87, 558-566. 

Oxidation of Trans Fats Unsaturated fats with trans double bonds are commonly referred to as trans fats. There has been much discussion about the effects of dietary trans fats on health. In their investigations of the effects of trans fatty acid metabolism on health, Yu and colleagues (2004) showed that a model trans fatty acid was processed differently from its cis isomer. They used three related 18-carbon fatty acids to explore the difference in /3 oxidation between cis and trans isomers of the same-size fatty acid. 

Griinari, J.M., Shingfield, K.J. 2002. Effect of diet on milk fat trans fatty acid and CLA isomer... 

Offer, N.W., Marsden, M., Phipps, R.H. 2001. Effect of oil supplementation of a diet containing a high concentration of starch on levels of trans fatty acids and conjugated linoleic acids in bovine milk. Anim. Sci. 73, 533-540. 

Opposing effects of certain individual fatty acids could have influenced the lack of a relationship between dietary fat and fat type with the risk of breast cancer. Well-conducted animal studies suggest that linoleic acid promotes development of mammary tumors, whereas saturated, monounsatu-rated, and trans fatty acids have little or no effect. In many cases, w-3 polyunsaturated fatty acids suppress tumor development. Conjugated linoleic acid (CLA) is the most potent anti-cancer fatty acid in that amounts of 1% or less of dietary fat can substantially inhibit the development of mammary tumors (Ip, 1997). 

Mensink, R.P., Zock, P.L., Katan, M.P., Hornstra, G. 1992. Effect of dietary cis and trans fatty acids on serum lipoproteinja] levels in humans. J. Lipid Res. 33, 1493-1501. 

A process with potential practical applicability is the hydrogenation of edible oils. Reduction of multiply unsaturated triglycerides with hydrogen over Ni-based catalysts is frequently used to gain autoxidative stability of edible oils. According to the Polanyi-Horiuti mechanism, multiple 1,2 or 1,4 diadsorption of the fatty acid tail with exclusively c/s-configuration around the double bonds causes cis-trans isomerisation, whilst the number of double bonds is being reduced. The trans-fatty acid chains have adverse effects on the human metabolism and must be minimized. 

The presence of a cis double bond introduces a kink that prevents packing of the fatty acid chains. Cis double bonds maintain fluidity. Trans fatty acids have no structural effect, relative to saturated fatty acids, and so they are rare. 

N. de Rons, Trans fatty acids, HDL-cholesterol, and cardiovascular disease risk Effects of dietary changes on vascular reactivity, Wageningen Universiteit, Wageningen, the Netherlands, 2001. 

Trans-Fatty Acids and Their Health Effects... 

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