Most of these physiological effects of CLA have been observed after feeding animals with mixtures of CLA isomers that contain mostly c9,t11 CLA and t10,c12 CLA in roughly equal amounts. In addition, animal studies have suggested that CLA has favorable effects on certain aspects of immune function ( Hayek et al, 1999 Turek et al, 1998 Wong et al, 1997 Yang et al, 2000), while ameliorating immune-mediated catabolism ( Cook et al, 1993 Miller et al, 1994).
![cis 9 trans 11 isomers cis 9 trans 11 isomers](https://d3i71xaburhd42.cloudfront.net/570e71a46bab8dcf0ecc4e505831d98d0ffd02d2/3-Figure1-1.png)
CLA has also been reported to decrease body fat while increasing lean body mass ( Blankson et al, 2000 Delany et al, 1999 West et al, 1998). Various positive health effects have been ascribed to CLA consumption, including anticarcinogenic ( Ip et al, 1994, 1997 Thompson et al, 1997), antiatherogenic ( Lee et al, 1994 Nicolosi et al, 1997), and antidiabetic activity ( Houseknecht et al, 1998). Unpublished data (TNO, Unilever) indicate that average intake for the Netherlands is about 200–400 mg CLA per day. In Germany average intake of CLA is estimated as 350 mg for women and 430 mg per day for men ( Fritsche & Steinhart, 1998b). Estimated average daily intake of CLA from these dietary sources ranges from 0.19 to 1.5 g of CLA ( Fritsche et al, 1998 Fritsche & Steinhart, 1998a) and varies for different countries ( Parodi, 1994). CLA concentrations in ruminant-derived products range from 3 to 7 mg CLA/g fat depending on source and processing of products ( Chin et al, 1994 Lin et al, 1995 Shantha et al, 1993, 1995). CLA is naturally present in milk and meat of ruminants due to its production by anaerobic bacteria in the rumen of these animals and can be produced industrially by partial hydrogenation of linoleic acid ( Chin et al, 1994 Parodi, 1994).
![cis 9 trans 11 isomers cis 9 trans 11 isomers](https://www.researchgate.net/publication/340347182/figure/download/fig1/AS:876590837805060@1586006950991/cis-9-trans-11-C9-increases-mitochondrial-fatty-acid-oxidation-and-affects-the.png)
Sponsorship: This study was supported by Loders Croklaan.Ĭonjugated linoleic acid (CLA) refers to a class of positional and geometric conjugated dienoic isomers of linoleic acid, of which cis-9, trans-11 (c9,t11) CLA and trans-10, cis-12 (t10,c12) CLA are the main isomers. This was seen in the CLA 50:50, but not in the CLA 80:20 group. Other aspects of immune function, ie DTH responses, NK cell activity, lymphocyte proliferation and production of TNF-α, IL1-β, IL6, IFN-γ, IL2, IL4, and PGE 2, were not affected.Ĭonclusion: This is the first study that suggests that CLA may beneficially affect the initiation of a specific response to a hepatitis B vaccination.
![cis 9 trans 11 isomers cis 9 trans 11 isomers](https://d3i71xaburhd42.cloudfront.net/cf1a086ab582a77f0102534f00639aa8a44a6b19/3-Figure1-1.png)
In subjects consuming CLA 80:20 glycerides this was 8/22 (36%). Results: Almost twice as many subjects reached protective antibody levels to hepatitis B when consuming CLA50:50 fatty acids (15/24, 62%) compared with subjects consuming the reference substance (7/21, 33%, P=0.075). The treatments were given as supplements in softgel capsules providing a total of 1.7 g (c9,t11+t10,c12) CLA fatty acids (50:50) or 1.6 g (c9,t11+t10,c12) CLA glycerides (80:20) per day in treatment groups for 12 weeks. Subjects and intervention: Seventy-one healthy males aged 31–69 y received one of the following treatments: (1) mixture of 50% c9,t11 CLA and 50% t10,c12 CLA isomers (CLA 50:50) (2) mixture of 80% c9,t11 CLA and 20% t10,c12 CLA isomers (CLA 80:20) and (3) sunflower oil fatty acids (reference). Objectives: To study the effects of two different mixtures of the main conjugated linoleic acid (CLA) isomers cis-9, trans-11 CLA and trans-10, cis-12 CLA on human immune function.ĭesign: Double-blind, randomized, parallel, reference-controlled intervention study.