ID 3165 - Sprzężony kwas linolowy

PL: Sprzężony kwas linolowy
EN: CLA (Conjugated linoleic acid)
Pdf: conjugated linoleic acid

Oświadczenie (2)

1. Charakterystyka żywności / składnika

The food that is the subject of the health claim is conjugated linoleic acid (CLA).
CLA refers to a group of positional and geometric isomers of linoleic acid that are characterised by the presence of conjugated dienes. CLA is a natural, but minor, component of fats from ruminant animals present in the human diet primarily in meat and dairy products. In nature, the most abundant isomer is cis-9, trans-11 (c9, t11), whereas in supplement forms CLA is typically sold as an equal mix of the two predominant isomers c9, t11 and t10, c12. Different isomers may have different effects.
The majority of the human intervention studies provided for the scientific substantiation of the health claims have used equimolar combinations of the c9, t11 and t10, c12 isomers, and therefore the Panel assumes that the food, which is the subject of the health claims, is an equimolar mixture of the CLA isomers c9, t11 and t10, c12
The Panel considers that the food constituent, an equimolar mixture of the conjugated linoleic acid (CLA) isomers c9, t11 and t10, c12, which is the subject of the health claims, is sufficiently characterised.

2.1. Udział w utrzymaniu lub osiągnięciu prawidłowej masy ciała (ID 686, 726, 1516, 1518, 2892, 3165)

The claimed effects are “weight management”, “body weight management” and “weight management, fat metabolism enhancement”. The Panel assumes that the target population is the general population.
The Panel assumes that the claimed effects refer to contribution to the maintenance or achievement of a normal body weight.
Weight management can be interpreted as contribution to the maintenance of a normal body weight. In this context, weight loss in overweight individuals even without achieving a normal body weight is considered to be a beneficial physiological effect.
The Panel considers that contribution to the maintenance or achievement of a normal body weight is a beneficial physiological effect.

3.1. Udział w utrzymaniu lub osiągnięciu prawidłowej masy ciała (ID 686, 726, 1516, 1518, 2892, 3165)

Most of the randomised, placebo-controlled trials (RCTs) which investigated the effects of CLA supplementation on body weight and body composition in humans that were cited in the consolidated list were included in the meta-analysis by Whigham et al. (2007) described below. One additional RCT not included in the meta-analysis was cited in relation to this claim (Steck et al., 2007).
Whigham et al. (2007) conducted a meta-analysis of randomised, double-blinded, placebo-controlled trials which investigated the effects of interventions using either equimolar mixtures of purified CLA isomers c9, t11 and t10, c12 (15 studies, doses ranging from 1g per day to 6.8 g per day, mean dose 3.2 g per day) or purified t10, c-12 and/or c9, t11 CLA isomers alone (three studies) on body weight and body composition either during or after weight loss. One of the weight loss studies considered was a 12-month uncontrolled follow-up of a previous 12-month intervention (Gaullier et al., 2005). Most interventions lasted 12 weeks or less. Among the 15 original RCTs which investigated the effects of supplementation with equimolar mixtures of the purified CLA isomers c9, t11 and t10, c12 on body weight during weight loss, only two found a significant reduction in body weight in the CLA group compared to the placebo (Watras et al., 2007; Gaullier et al., 2007), whereas no differences between groups were observed in the remaining 13 RCTs (Blankson et al., 2000; Gaullier et al., 2004; Mougios et al., 2001; Smedman and Vessby, 2001; Pinkoski et al., 2006; Berven et al., 2000; Riserus et al., 2002; Malpuech-Brugere et al., 2004; Atkinson, 1999; Petridou et al., 2003; Eyjolfson et al., 2004; Taylor et al., 2006; Lambert et al., 2007). No significant differences in body weight between CLA and the placebo group were observed using either 3.2 g per day CLA or 6.4 g per day CLA (equimolar combination of the c9, t11 and t10, c12 isomers) for 12 weeks in the RCT by Steck et al. (2007) which was not included in the meta-analysis.
The meta-analysis by Whigham et al. (2007) also reviewed three studies on the effects of CLA supplementation on body weight maintenance after weight loss (Kamphuis et al., 2003; Larsen et al., 2006; Whigham et al., 2004), none of which observed significant differences between CLA and placebo groups with regard to body weight changes.
In weighing the evidence, the Panel took into account that 14 out of 16 intervention studies in humans did not report a significant effect of CLA on body weight, that most of the studies considered were short-term (12 weeks or less), and that none of the three studies on body weight maintenance after weight loss showed a significant effect of CLA compared to placebo.
The Panel concludes that a cause and effect relationship has not been established between the consumption of an equimolar mixture of the CLA isomers c9, t11 and t10, c12 and contribution to the
maintenance or achievement of a normal body weight.

Warunki i możliwe ograniczenia stosowania oświadczenia

The effective dose of CLA is 1.7 g -3.4g/a 50:50 mixture of c9, t11 and t10, c12 is of CLA per day for 12 weeks