CLA (conjugated linoleic acid) in contemporary food and its positive influence on body composition

CLA (conjugated linoleic acid) in contemporary food and its positive influence on body composition

Remo Jutzeler, Ing. Appl Food Sciences FH, MAS Nutrition & Health ETHZ

Previous studies on CLA intake through nutrition showed strongly varying and relatively low amounts, but did not consider animal-adapted feeding strategies nor biosynthesis in human metabolism out of precursors. Dairy food and meat, respectively animal fat, are the only food sources of CLA and its precursor vaccenic acid, of which CLA is partly formed in humans. By natural feeding strategies, i.e. pasture access, strikingly higher quantities of CLA and vaccenic acid are possible in those food categories. Grass-based feeding methods provided »2-2.5fold higher quantities of CLA than standard corn- and soy-based feeding. A focussed nutrition, respecting nutrition guidelines, with such foods permits a CLA intake clearly above 1000 mg up to more than 3000 mg/day (1).

Regarding the effect of CLA supplementation on body composition there are now already 22 studies of a longer duration between 2 weeks and 12 months available, whereof one was prolonged to 24 months. CLA intake during at least 12 weeks with ³ 3 g/day may reduce body fat mass and maintain muscle mass during restricted diets, and also reduces body fat regain after cessation of a diet. The question arises, if CLA may be considered as a semi-essential nutrient, which is not present in today’s’ food in adequate amounts anymore.

(1) R. P. Jutzeler van Wijlen, P. C. Colombani: Grass-based ruminant production methods and human bioconversion of vaccenic acid with estimations of maximal dietary intake of conjugated linoleic acids. Int Dairy J. In Press, Accepted Manuscript