Efficacy of Oral Micronutrient Supplementation on Linear Nail Growth in Healthy Individuals

Introduction: Several studies demonstrate the effects of the oral supplementations on the skin while there are limited data for their effects on the nail quality in healthy individuals. Only placebo controlled double blind studies could provide the reliable data considering the physiologic nail growth. Objective: The objective of this study was to evaluate the efficacy of consumption of a micronutrient supplementation on linear nail growth and thickness. Subjects and Method: 60 healthy female volunteers aged 35 to 65 years old were enrolled, randomized blindly in treatment and placebo groups, taking one tablet per day for 3 months. The evaluation was performed on D0 and D90 ± 3 days by measuring the linear nail growth, nail thickness by high frequency ultrasound imaging and also subjects’ self-assessment. Results: All 60 subjects finished the study without any serious adverse event. At D90 both groups revealed a significant linear nail growth (5.20 ± 0.35 for treatment group (p = 0.001) and 5.15 ± 0.30 for placebo group (p = 0.001)). However, the difference between the treatment and placebo group was statistically significant (p = 0.01) demonstrating the efficacy of oral supplementation on linear nail growth. No significant difference was observed at D90 for nail thickness measured with HFUS between 2 groups. The self-assessment score regarding ?brittle nails? and ?split nails? was diminished non-significantly in both groups. Conclusion: The results observed in this trial revealed that the oral micronutrient supplementation can provide beneficial effect on nail growth. This result may be due to the whole formula as the single vitamin treatment like biotin was shown to be non-effective. A longer study would be needed to confirm the efficacy on nail thickness.