Conjugated linoleic acid (CLA) is an expression that refers to a group of isomers (i.e. molecules with the same number of atoms and double bonds, but not in the same position) of linoleic acid characterised by the fact that the two double bonds are interspersed with a single bond. This characteristic gives the molecule (and the double bonds therein) the name conjugate. Generally, the double bond conjugation is present at positions 9 and 11 or 10 and 12 (from the last carbon atom in the molecule).

Function

Theoretically, the intake of CLA would promote the emptying of adipocytes and the reduction of adipocyte volume (associated, of course, with a reduced willingness of these to refill). However, research has shown conflicting results. In fact, although the theoretical effect seems to be proven in rats, in humans some researchers, such as Haugen (2004) and Larsen (2006), have come to the conclusion that CLA is not really effective in the slimming process. Others, however, such as Erling and Gudmundseng, have found real efficacy in the molecule. Gaullier (2002) hypothesised that the reason why CLA did not work in some of the studies on men is that CLA supplements do not contain ‘good isomers’, i.e. the most active subcategory of CLA.

Negative notes

It appears that prolonged use of CLA may cause alterations in the blood profile of cholesterol and insulin. Therefore, prolonged use of CLA products should be avoided.

Form and dosage

CLA supplements are available on the market in tablet form. In terms of dosage, doses of 3g/day are associated with a reduction in fat mass. It is desirable to divide the daily dose into three different doses.