ID 1671 - Tryptofan

PL: Tryptofan
EN: Trytophane
Pdf: L-tryptophan

Oświadczenie (2)

1. Charakterystyka żywności / składnika

The food constituent that is the subject of the health claims is L-tryptophan.
L-tryptophan is an indispensable amino acid provided by mixed dietary protein intakes from different sources. L-tryptophan can also be consumed in the form of food supplements. The content of L-tryptophan in foods can be measured by established methods.
The Panel considers that the food constituent, L-tryptophan, which is the subject of the health claims, is sufficiently characterised.

2.1. Utrzymanie prawidłowego snu (ID 596, 1671)

The claimed effects are “mental health” and “mental and nerve function”. The Panel assumes that the target population is the general population.
In the context of the proposed wordings, the Panel assumes that the claimed effects refer to the maintenance of normal sleep. Normal sleep, including normal sleep onset latency, efficiency, duration and quality can be measured by validated methods.
The Panel considers that maintenance of normal sleep is a beneficial physiological effect.

3.1. Utrzymanie prawidłowego snu (ID 596, 1671)

A number of references provided for the scientific substantiation of the claim did not address relevant endpoints with respect to sleep, or did not report on L-tryptophan. Four references were narrative reviews and did not provide any original data for the scientific substantiation of the claimed effect. The Panel considers that no conclusions can be drawn from these references for the scientific substantiation of the claimed effect.
Three placebo-controlled studies examined the effects of L-tryptophan on measures of sleep.
Hartmann and Spinweber (1979) studied the effects of either 0 g, 0.25 g, 0.5 g or 1 g of L-tryptophan taken 20 minutes prior to bedtime on sleep latency and efficiency (defined as the ratio of total sleep time over total time in bed) in 15 normal males with mildly disturbed (insomniac) sleep (i.e. reporting sleep latencies over 30 minutes). The Panel notes that there were insufficient details on treatment regimens, including the nature of the products administered, on whether participants and researchers were blind to the dose, and on how the treatments were counter-balanced, and that there were other weaknesses, including the small number of subjects and the use of acute doses of L-tryptophan on only one occasion. The Panel notes that no conclusions can be drawn from this study for the scientific substantiation of the claimed effect.
Hudson et al. (2005) conducted a double-blind, randomised placebo-controlled trial on the effects of L-tryptophan on measures of total sleep time, sleep efficiency, time awake, and sleep quality in 57 adult subjects who met the DSM IV criteria (Diagnostic and Statistical Manual of Mental Disorders, 4th edition) for primary insomnia. Subjects were asked to stop sleep medication during the trial. Sleep measures were obtained by completion of sleep diaries. The Panel notes that patients
received various food bars, which varied in L-tryptophan content, and primary analysis showed that L-tryptophan had no effect on measures of sleep across the three weeks of the study.
The third study evaluated sleep onset latency and sleep quality in 10 patients with sleep disturbance who were administered 5 g of L-tryptophan by intra-venous infusion compared to physiological saline solution (Korner et al., 1986). The Panel notes that L-tryptophan was given intravenously at a dose greater than the conditions of use provided in the consolidated list. The Panel notes that no conclusions can be drawn from this study for the scientific substantiation of the claimed effect.
In weighing the evidence, the Panel took into account that the only intervention study which could be used to substantiate the claimed effect found no effect of L-tryptophan on measures of sleep.
The Panel concludes that a cause and effect relationship has not been established between the consumption of L-tryptophan and maintenance of normal sleep.

Warunki i możliwe ograniczenia stosowania oświadczenia

100-750 mg per day