The Effect of Dietary Supplementation of Crocetin for Myopia Control in Children: A Randomized Clinical Trial

Abstract

The prevalence of myopia has been increasing in recent years. The natural carotenoid crocetin has been reported to suppress experimental myopia in mice. We evaluated the effects of crocetin on myopia suppression in children. A multicenter randomized double-blind placebo-controlled clinical trial was performed with 69 participants aged 6 to 12 years, whose cycloplegic spherical equivalent refractions (SER) were between −1.5 and −4.5 diopter (D). The participants were randomized to receive either a placebo or crocetin and followed up for 24 weeks. Axial length (AL) elongation and changes in SER were evaluated for 24 weeks. Both written informed assent from the participants and written informed consent from legal guardians were obtained in this study because the selection criteria of this trial included children aged between 6 and 12 years old. This trial was approved by the institutional review boards. A mixed-effects model was used for analysis, using both eyes. Two participants dropped out and 67 children completed this trial. The change in SER in the placebo group, −0.41 ± 0.05 D (mean ± standard deviation), was significantly more myopic compared to that in the crocetin group, −0.33 ± 0.05 D (p = 0.049). The AL elongation in the placebo group, 0.21 ± 0.02 mm, was significantly bigger than that in the crocetin group, 0.18 ± 0.02 mm (p = 0.046). In conclusion, dietary crocetin may have a suppressive effect on myopia progression in children, but large-scale studies are required in order to confirm this effect.

Food Supplements in the Treatment of Ophthalmic Diseases: Preclinical and Clinical Studies

“…In a randomized clinical trial, 69 myopic children aged 6 to 12 years received either a placebo or oral crocetin for 24 weeks. The spherical equivalent refractive error progressed during the 6 months of the study by -0.41± 0.05 Diopters in placebo controls, and by −0.33 ± 0.05 Diopters in crocetin treated (p < 0.05); the axial length increased by 0.21 ± 0.02 mm in placebo controls, and by 0.18 ± 0.02 mm in crocetin treated (p < 0.05), thus showing the potential effects of crocetin in slowing down myopia progression [489].…”

Crocetin: A Systematic Review

“…The axial length (AL) elongation was significantly smaller in the crocetin group (0.18 ± 0.02 mm) than that in the placebo group (0.21 ± 0.02 mm). In conclusion, dietary crocetin may have a therapeutic effect on myopia in children (Mori et al, 2019).…”

“…No adverse reactions associated with crocetin were reported during the clinical study. All adverse events reported were unrelated to crocetin administration (Mori et al, 2019). In a clinical study evaluating the pharmacokinetics of crocetin, 10 healthy volunteers had no significant adverse events after oral administration of 22.5 mg crocetin (Umigai et al, 2011).…”

Axial length shortening in a myopic child with anisometropic amblyopia after wearing violet light-transmitting eyeglasses for 2 years

“…The choroidal thickness was measured using spectral-domain optical coherence tomography (SD-OCT) (RS-3000, Nidek, Aichi, Japan) using ImageJ software (National Institutes of Health, Bethesda, MD) as reported previously. 9 , 10 , 11 , 12 The intraocular pressures were 13 mmHg bilaterally. We diagnosed ametropic amblyopia and prescribed non-violet light-transmitting eyeglasses.…”

“…A number of treatments have been used to retard myopia progression including outdoor activities, 6 orthokeratology, 7 low-dose atropine eye drops, 8 and dietary supplementation; 9 however, myopia currently cannot be stopped or improved by a non-surgical method.…”