Konjuge linoleik asit: Obezitedeki etkileri

Obezite büyük bir oranda genetik bir hastalık olmakla birlikte, gelişimini sosyal, kültürel, bilişsel, biyolojik ve çevresel etmenler etkilemektedir. Obezite; tip II diabet, kalp hastalıkları, kanser, hipertansiyon, osteoartirit gibi sağlık sorunlarının oluşumuna katkıda bulunmaktadır. Son yıllarda obezitenin tedavisinde diyet eklerinin kullanımı yaygınlaşmakta ve ağırlık kaybında hastalar tarafından sihirli bir güç olarak görülmektedir. Literatürde zayıflama amacıyla içlerinde konjuge linoleik asitin de bulunduğu yaklaşık 50 ek ve 125 ticari preparat olduğu belirtilmektedir. Konjuge linoleik asitler (KLAs), başta süt ürünleri olmak üzere besinlerde doğal olarak bulunan konjuge oktadekadionik asit isomerlerinin bir grubudur. Yapılan çalışmalarda çoklu doymamış yağ asitlerinin (ÇDYA) bir grubu olan KLA 'nın metabolik ve anUobezite aktivitesine dikkat çekilmiştir. Deneysel çalışmalarda aterosklerozisi azaltıcı etkisinin yanı sıra, sıçanların diyetlerine ilave edilen KLA ile vücut ağırlıklarının % 60 oranında azaldığı gösterilmiştir. İnsan çalışmalarında ise KLA 'nın kas dokusunu artırarak vücut yağını azalttığı, ancak bu etkisinin beklenenden daha az olduğu belirtilmiştir. Bu derlemede KLA 'nın özellikleri anlatılmış ve obezitede KLA 'nın etkisini gösteren çalışmalar özetlenmeye çalışılmıştır.

Conjugated linoleic acid: Effect on obesity

Mostly a hereditary disease, the development of obesity is influenced by social, cultural, cognitive, biological and environmental factors. Obesity contributes to type 2 diabetes, coronary heart disease, cancer, hypertension and osteoarthritis. In recent years the use of dietary supplementations has become common and perceived as a magic power for weight loss by the patients. In literature, nearly 50 supplements and 125 commercial preparates are reported among which is also conjugated linoleic acid. Conjugated linoleic acids (CLAs) are a group of octadecadionic acid isomers which are naturally found in foods, especially in dairy products. In a number of studies, the metabolic and anti-obesity activity ofCLA as a group of polyunsaturatedfatty acids have been emphasized. In experimental studies, besides its decreasing effect on atherosclerosis, when added to the diets of mice, CLA caused weight loss by 60 %. In human studies CLA declined body fat by increasing muscle tissue, but the observed effect was less than the expected. In this review, the properties of CLA were described and the studies on the effects of CLA on obesity were summarized.

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1.Riserus A, Brisman K. Treatment with dietary trans 10 cis 12 conjugated linoleic acid causes isomer-spesific insulin resistance in obese men with the Metabolic Syndrome. Diabetes Care 2002, 25: 1516-1521.
2. Terpstra HM. Effect of conjugated linoleic acid on body composition and plasma lipids in humans: an overview of the literature. Am J Clin Nutr 2004, 79: 352-361.
3. Georgy SL, Kelly ND. Conjugated linoleic acid : A review. Alternative Medicine Review 2001, 6: 367-382.
4. Blankson H, Jacob A, Fapertun H, et al. Conjugated linoleic acid reduces body fat mas in overweight and obese humans, J Nutr 2000, 130: 2943-2948.
5. Bclury MA. Dietary conjugated linoleic acid in health: physiological effect and mechanisms of action. Annu Rev Nutr 2002, 22: 505-531.
6. Mac Donalds HB. Conjugated linoleic acid and disease prevention: a review of current knowledge. J Am Coll Nutr 2000, 19 : 111-118.
7. Wahle WJ, Hey s SD, Rotondo D. Conjugated linoleic acids: are they benefical or detrimental to health? Prog Lipid Res 2004, 43:553-587.
8. Park Y, Albright KJ, Liu W, et al Effect of conjugated linoleic acid on body composition in mice. Lipids 1997, 32: 853-858.
9.Rahman SM, Wang YM, Han SY, et al. Effects of short-term adninistration of conjugated linoleic acid on lipid metabolism in white and brown adipose tissues of starved/refed Otsuka Long-Evans To kus h ima fatty rats. Food Res Int 2001, 34: 515-520.
10. Pariza MV, Park Y, Cook ME. The biologically active isomers of conjugated linoleic acid. Prog Lipid Res 2001, 40: 238-298.
11. Park Y, Storkson JM, Albright KJ, et al. Evidence that the trans-10, cis-12 isomer of conjugated linoleic acid induces body composition changes in mice. Lipids 1999, 34:235-241.
12. Whigman LD. O'Shea M, Moheda IC, et al. Safety profile of conjugated linoleic acid in a 12-month trial in obese humans, Food Chem Toxicol 2004, 42:1701-1709.
13. Kamphuis JW, Lejeune GM, Saris WHM, et al. The effect of conjugated linoleic acid supplementation after weight loss on bodyweight regain, body composition and resting metabolic rate in overweight subjects. Int J Obes Relat Metab Disord2003, 27:840-847.
14. Gaullier JM, Halse J, Hove K, et al Supplemantation with conjigated linoleic acid for 24 months is well tolerated by and reduces body fat mass in healthy, overweight humans. J Nutr2005, 135:778-784.
15. Zambell KL, Keim NL, Van Loan MD, et al. Conjugated linoleic acid supplementation in humans: effects of body composition and energy expenditure. Lipids 2000, 35: 777-784.
16. Smedman A, Vessby B. Conjugated linoleic acid supplementation in humans-metabolic effects. Lipids 2001, 36: 773-778.
17. Medina EA, Horn WF, Keim NL, et al. Conjugated linoleic acid supplementation in humans: effects on circulating leptin concentrations and appetite. Lipids 2000, 35:783-788.