Within two months of supplementation, hair density was shown to have significantly increased by 30 per cent.
Findings of the study were published in Health Science Reports.
Taking place between August 2018 and June 2019, the double-blind, randomised, placebo-controlled study recruited 76 Chinese women aged 45 to 60.
They were randomised to take the placebo or three supplement pills each containing 50mg of Pycnogenol – a proprietary bark extract from the French maritime pine tree provided by Geneva-based Horphag Research, which also funded the research.
Hair density significantly went up within two months of supplementation.
For instance, mean hair density increased from the baseline of 225.8 hairs / cm2 to 293.6 after two months of supplementation – a statistically significant increase of 30 per cent.
By the end of the six-month trial, mean hair density was 278.6 hairs / cm2 in the intervention group. Although this was a drop from the second month mark, this was nonetheless a significant increase from the baseline.
On the other hand, even though mean hair density had also increased in the placebo group by the second- and sixth-month mark of the study, the change from baseline was not statistically significant.
Association with resting flux
The increase in mean hair density was associated with a decrease in the resting flux of the scalp skin, which in is linked to an improvement in scalp microcirculation.
Median blood volume flux in both the placebo and intervention group was seen, based on photoplethysmography, which is used to detect blood volume changes in the body tissue.
However, only statistically significant change was reported in the intervention group.
Specifically, median blood volume flux declined from 2.30 to 1.80 by the second month of the trial and further shrunk to 1.30 by the end of the trial. This was a reduction of 21 per cent and 44 per cent respectively.
In comparison, median blood volume flux reduction occurred to a smaller degree in the placebo group.
Median blood volume flux was down from 1.95 to 1.85 by the end of second month and further decreased to 1.55 after six months.
Another finding was that transepidermal water loss (TEWL) had decreased significantly by 2.5 in the intervention group, while it went up by 6.0 instead in the placebo group two months into the trial.
An earlier trial also showed that TEWL had decreased in individuals taking 100mg of Pycnogenol over three months during autumn in Shanghai.
On the other hand, there was no significant change in hydration of scalp skin in the two groups.
Concluding the findings, the researchers said that although the precise mechanism behind Pycnogenol was not known, the improvement in hair density was associated with a decrease in resting flux of the scalp skin, which was also seen in an earlier study.
The researchers also suggested that the antioxidative capacity of Pycnogenol might have contributed to the improvement in hair density.
Source: Health Science Reports
An oral French maritime pine bark extract improves hair density in menopausal women: A randomized, placebo‐controlled, double blind intervention study
Authors: Cai C et al