Efficacy of a wheat polar lipid complex in reducing hair loss and improving hair growth in healthy women: A randomized, double‐blind, placebo‐controlled clinical study

Hair loss is a major source of psychological distress for affected people. Safe and natural ingredients are therefore needed to help reduce hair loss and stimulate hair growth. This pilot clinical study aimed at exploring the efficacy of a wheat polar lipid complex (WPLC, Ceramosides™), containing sphingolipids and digalactosyl diglycerides, on hair characteristics improvement in women showing acute hair shedding.


INTRODUCTION
Hair is a cosmetic attribute essential for personal identity.While men are mostly affected, it is estimated that 50% of women will experience noticeable hair loss throughout their lives [1].This leads to anxiety and psychological burdens in women, for which hair is strongly associated with femininity, attractiveness and self-esteem [2].Apart from female pattern hair loss, which involves a progressive transformation of terminal into vellus hair and therefore leads to a permanent alopecia [3], hair loss can be very often diffuse and temporary.Such a condition can be triggered by diverse events like emotional or physiological stress (surgical trauma or high fever), childbirth or sudden weight loss [4].Indeed, dietary deficiencies and caloric restriction can lead to hair shedding.In particular, low food intake of proteins, essential fatty acids, zinc, iron and vitamin D has been proposed as a possible cause [4,5].Finally, seasonal change is also reported as a triggering factor, as an increased frequency of hair shedding has been observed between July and October [4].The resulting hair shedding is time-limited and generally resolves naturally.
Hair is a complex structure consisting of the visible shaft and, below the scalp, a hair bulb, as well as a highly vascularized dermal papilla.The development of hairs relies on cycling [5,6].A growth phase (anagen) leads to hair production and constant elongation of the shaft for 2-5 years.Typically, 85%-90% of scalp hairs are in that phase.Growth ceases with a three to six-week-long apoptosis-driven regression of the follicle (catagen).Finally, the shaft matures into a club hair (telogen), which eventually sheds.About 10%-15% of the scalp hairs are typically in that last phase.This cycling process ensures the regular renewal of each hair of the scalp.It is under the tight control of several growth factors, including fibroblast growth factors (FGF), transforming growth factors (TGF), insulin growth factors (IGF) and many others [7,8].
Hair thinning and shedding can result from alterations in the hair cycle.In particular, the early entry of the hair into the telogen phase is defined as 'telogen effluvium' [4].First described in 1961 by Albert Kligman, telogen effluvium (TE) is the most common cause of temporary hair loss in women and is characterized by a diffuse increased loss of normal telogen hairs with a proportion of telogen hairs that can reach over 30% [9].The term 'telogen effluvium' refers to the premature termination of anagen stage of hair life cycle [10].Klingman suggested that a stressful event can trigger an acceleration of the hair cycle of anagen hair follicles, through unknown mechanisms, leading to a precipitated telogen phase and an excessive hair shedding about 2-3 months after the precipitating event [11].In most cases, TE duration is shorter than 6 months [12], and therefore called 'acute TE'.This condition resolves spontaneously in 95% of cases [4].Improvement generally occurs within 3-6 months, and the complete recovery is achieved in about a year [9].However, the resulting excessive hair shedding significantly affects the quality of life of the individuals concerned [13].The association of TE with age is unclear; however, elderly women are reported to be more susceptible to acute TE [4].Indeed, hormonal and age-related physiologic changes occurring in women's midlife, such as the onset of menopause, can lead to alterations in hair growth and quality [14].Oestrogens being involved in the regulation of the hair cycle; the decrease in ovarian oestrogen production driven by menopause has been associated with a reduction in anagen hair in postmenopausal women [15].
Although some anti-hair loss treatments exist, they are mainly devoted to pathological and hormonal hair loss [1,16], and there is currently no targeted treatment for the management of TE [4,17].These medications are associated with side effects, highlighting the need to seek safe and natural ingredients to help reduce hair loss and stimulate hair growth [18].Nutritional supplementation proved efficient in correcting specific dietary disorders or nutrient deficiencies in relation to hair quality [19].Since 2018, a few clinical studies claim that supplements including vitamins, minerals, amino acids and/or peptides, and sometimes a few additional ingredients, also have a positive impact [20][21][22][23].However, very few plant extracts were demonstrated to be efficient in reducing hair loss.These ingredients generally rely on the proliferation of hair follicle keratinocytes in relation to the stimulation of growth factors [24].
WPLC supplement contains 98% of polar lipids, essentially sphingolipids, among which glucosylceramides and digalactosyl diglycerides (DGDG), a natural emulsifier [25].If several studies showed benefits of ceramide supplementation for the skin [25][26][27][28][29][30][31], little is known about its effects on hair apart from the claims of the cosmetic industry to use them in hair conditioners to flatten the outer cuticle cells, improving smoothness and shine.As there is no literature report supporting that ceramides and/or sphingolipids improve hair growth and condition, a randomized, double-blind, placebo-controlled study was conducted using acute TE as a clinical model of temporary and diffuse hair loss.Sixty-six healthy women experiencing excessive hair shedding were evaluated after 56 and 84 days to assess the effect of WPLC supplementation on hair loss, growth, strength and aspect, as well as scalp sebum content.

Study design and ethics
This clinical study was designed as a randomized, parallelgroup, double-blind, placebo-controlled trial and aimed to investigate the effects of daily oral intake of wheat polar lipids over 84 days on hair loss and hair aspect.Assessments were carried out on Day 0 (D0), before starting supplementation to determine baseline results of all parameters, and after 56 (D56) and 84 days (D84) of supplementation.The diagram of the study design is provided in Figure 1.
Treatment allocation, evaluations and data analyses were performed blindly.
This study was approved on 28 July 2022, by an independent ethics committee for non-pharmacological clinical evaluations (Complife Italia Protocol H.E.HU.TE.NHL00.060.12.00_IT0003492/22) and conducted in Complife facilities (Italy).It strictly followed the 1975 Declaration of Helsinki principles, revised in 2013.All participants received detailed information, and all gave written informed consent before being recruited.The clinical protocol was registered with www.clini caltr ials.gov (NCT05954039).

Intervention
The WPLC supplement and the placebo were provided in identical opaque capsules, whose composition is described in Table 1.Briefly, active capsules contained 15 mg of wheat polar lipids complex (Ceramosides™, Seppic, France) in powder form, while placebo capsules contained no active substances.During the 84 days of the study, participants took two capsules every evening before sleeping.

Participants
A total of 66 healthy women with all hair types were recruited.Aged between 24 and 64 years old, they were Caucasian women presenting excessive hair shedding with a minimum of 15% of hairs in the telogen phase as determined by phototrichogram evaluation (see description below).The proportion of hair in the telogen phase ranging generally between 10% and 15% in physiological conditions, the threshold of 15% is therefore suggestive of telogen effluvium.All participants were also complaining about brittle and thin hairs.These participants were randomly assigned to the placebo or the WPLC group.During the entire study, participants, investigators and collaborators were kept blind to group assignment.
In addition to protocol adhesion, inclusion criteria were the absence of use of any anti-hair loss treatment in the 3 months preceding the study, the absence of use of any treatment interfering with hair shedding, growth and/or condition during the study as well as the willingness not to cut hair.Besides, participants were asked not to change their daily routine (including contraception when applicable).Participants with a disease and/or a treatment (including changes in oestrogen-progesterone contraception or hormonal treatment) susceptible to interfere with the study were excluded, as were participants with skin/scalp conditions liable to interfere with evaluations.Participants who underwent radiotherapy, chemotherapy and/or scalp surgery were also not considered.Additional exclusion criteria were nutritional disorders, hair diseases and excessive or fluctuating hair shedding for more than 6 months.Finally, participants who have been using systemic treatment affecting hair growth, including systemic or local androgenetic alopecia, for more than four consecutive weeks during the last 24 weeks before the inclusion visit were excluded, as were pregnant/breastfeeding women or those planning a pregnancy during the study.
Participants were also asked to fill in a daily diary specifying any significant change in their alimentary habits.

Compliance of participants to the treatment
At each visit (D56 and D84), the number of capsules used by participants was recorded.A compliance (100 x number of capsules taken/number of capsules to be taken) of over 80% was required.

Outcome assessment
All outcomes were assessed under controlled environmental conditions (22 ± 2°C with 40%-60% relative humidity).Participants were left to acclimate for 15-20 min before any evaluation.
To avoid interference with assessments, participants were asked not to use anti-dandruff and/or anti-fungal shampoo, nor to bleach and/or perm their hair in the 2 weeks preceding a visit.They were also asked not to wash their hair 48 h before visits nor to use any hair care products (e.g., gel, hairspray, wax and foam) between this last shampoo and visits.
The primary outcome was the anti-hair loss efficacy at D84 as evaluated by objective assessments.Hair characteristics (diameter and elongation at break point) and scalp sebum content at D84 were also considered.The secondary outcomes were these same parameters at an earlier time (D56), as well as the clinical evaluation of hairs, product acceptability and the participant's perceived efficacy.

Phototrichogram analyses
The phototrichogram is a non-invasive method allowing reliable and objective evaluation of the efficacy of anti-hair loss treatments [32].Assessments were performed before (D0) and after 56 (D56) and 84 (D84) days of supplementation, focusing on anagen hair density and proportion, as well as telogen hair density and proportion.Analyses were carried out on the receding hairline from the frontotemporal regions or the vertex using a TrichoScan® (Tricholog GmbH & Datinf GmbH, Germany), as described by Hoffmann [32].Briefly, macro-photographs were taken at each time point on a 1.8 cm 2 diameter scalp area.The number of hairs in anagen/telogen phases was counted using TrichoScan® software (Tricholog GmbH & Datinf GmbH, Germany).Anagen and telogen hair densities were calculated by dividing the number of hairs in anagen or telogen phase by the surface area.

Pull test
Pull tests were carried out at each visit (D0, D56 and D54) by the same trained dermatologist.A gentle traction was exerted on a bunch of approximately 60 hairs in three areas of the scalp (frontal, temporal and occipital regions), counting the number of tugged hairs.

Hair diameter and elongation
Hair diameter and elongation at break point were analysed at baseline (D0) and after 84 days of supplementation (D84) on hairs sampled from a region close to the one used for the phototrichogram analysis.The hair diameter from five hairs was calculated using an optical microscope and an image analysis software.
Hair elongation was measured with a Tensolab 2512A dynamometer (Mesdan S.p.A., Italy) using UNI EN ISO 5079:1998 standard procedure.Measurements were performed with single hair settings, an elongation velocity of 50 mm/min and a pre-tension of 5 cN.For each participant and time point, the average maximum elongation before breakage (% of initial hair length) of 15 hairs was determined.

Hair growth
Hair growth was evaluated at D84 by measuring the average length of five hairs from a scalp region (shaved at D0) close to the one chosen for phototrichogram evaluation (mid-vertex).

Scalp sebum content
The scalp sebum content was also quantified.Measurements were performed at D0, D56 and D84 using a Sebumeter® SM 815 (Courage+Khazaka Electronic GmbH, Germany).Sampling was performed on the central hairline using a 64 mm 2 mat synthetic tape.

Clinical evaluation
A trained dermatologist performed a clinical evaluation at each visit (D0, D56 and D84).Hair density and volume were scored using a 0-10 visual analogue scale, with 0 corresponding to a very light density/volume and 10 to a very important density/volume.Participants were considered improved if their grade at D56/84 was improved compared with D0.

Self-assessment questionnaire
During the last visit (D84), participants filled out a 17-item questionnaire concerning their feelings about their hair and scalp conditions.The questions were: 'After the use of the product, you feel that…' '…your hair is more beautiful', '…your hair is healthier', '…your hair quality improved', '… your hair is stronger', '…your hair is thicker', '…your hair is less prone to breakage', '…your hair has more volume', '…your hair is shinier', '…your hair is softer', '…your hair is less dry', '…your hair is easier to style', '…your hair grows faster', '…you lose fewer hairs', '…your hair has fewer split ends', '…your hair is less greasy', '…your scalp is more covered', and '…your scalp is more moisturized'.Possible answers were 'completely agree', 'agree', 'disagree', or 'completely disagree'.'Completely agree' and 'agree' were considered positive scores.

Statistical analysis
Relying on Guidelines for pilot studies that recommend recruiting 10-40 participants per group [33], 33 participants per group were enrolled.One participant from the placebo group withdrew from the study for personal reasons, leaving 32 participants in this group.Statistical analyses were performed on the Per Protocol population.The flow chart is provided in Figure 2.
Means and standard errors of the mean were calculated for each parameter of each group and at each time point.Percentages of variation versus D0 were also calculated for each time point and each participant.The mean and SEM of these percentages were then calculated for each group.
The intra-group statistical comparison was performed on raw data.When following a normal distribution, the comparison was performed using one-way repeated measures analysis of variance (RM-ANOVA) followed by post hoc Dunnett's test for multiple comparisons to a control (D0).Otherwise, Friedman test was used, followed by Dunn's test for pairwise multiple comparisons of the ranked data.
Inter-group statistical comparisons were performed on the percentages of variation versus D0.Data with normal distribution were analysed with one-way analysis of variance (ANOVA), followed by post hoc Šidák's correction for multiple comparisons.For not normally distributed data, a Kruskal-Wallis test was applied, followed by Dunn's test for pairwise comparisons.Statistical analyses were performed using GraphPad Prism 9.5.0 software.

Study participants
The descriptive statistics from the placebo and WPLC groups are presented in Table 2.The two groups showed no significant difference at baseline and included a minimum of 10 postmenopausal women.The enrolled women presented mild-to-moderate hair loss at baseline, as shown by the proportion of hair in the telogen phase below 20%.Food diaries also indicated that participants did not significantly change their habits throughout the study (data not shown).
F I G U R E 2 Flow chart of the study participants.
Capsule count revealed an overall treatment compliance of 97.4% ± 4.4%, with a minimum of 80% in the placebo group and 87% in the WPLC group.No participant reported adverse effects during the study.

Effects of WPLC supplementation on telogen and anagen parameters
Phototrichograms were performed at each visit (D0, D56 and D84) to gain insight into the evolution of the hair cycle by assessing the proportion and density of hairs in telogen or anagen phases (Figure 3).Data are presented in Table S1.
In the placebo group, the density of hairs in the telogen phase significantly decreased with time and was already noticeable at D56 (−8.1%), reaching a minimum at D84 (−8.3%).This lower density was significant in terms of proportion at D84 (−10.5%).Upon WPLC supplementation, telogen hair density decreased faster than in the placebo group, already reaching −17.7% at D56 compared with D0 and −23.5% at D84. Besides, compared with D0, the proportion of telogen hair was already significantly reduced at D56 (−17.9%) and showed a minimum at the end of the supplementation period (−27%).This minimum corresponds to a proportion of 14.0% ± 0.6% of telogen hair, a ratio that is below the threshold of 15% generally admitted to consider telogen effluvium.Furthermore, the decrease in the density and proportion of telogen hairs was faster and more pronounced in the WPLC group than in the placebo group.Considering anagen hairs in the placebo group, compared with D0, their density increased at D84 (+5.6%), as did their proportion (+2.5%).In the WPLC group, anagen hair density was already improved by +4.6% at D56, reaching a maximum of +11.9% at D84.Similarly, anagen hair proportion rose by +4.3% at D56 and + 6.5% at D84.Therefore, WPLC supplementation induced a stronger increase in the anagen hair density and proportion at D56 compared with the placebo and still did so at D86.

Effects of WPLC supplementation on the number of hairs tugged upon pull test
The estimate of hair loss severity by pull tests (Table 3) indicated that both placebo and WPLC groups presented reduced hair loss.If this decrease was only significant at D84 in the placebo group (−38.2%), it was already relevant after 56 days in the WPLC group (−14.7%),reaching a minimum at D84 (−47.9%).The difference between both groups was significant at D56 and at the limit of significance at D84.

Effects of WPLC supplementation on hair characteristics and growth
Hair diameter and elongation at break point were monitored at the end of the study (D84), and results were compared with those of D0 (Table 4).In the placebo group, none of these two features showed any variation.In the WPLC group, hairs presented a trend towards a slight diameter enlargement (+4.4%).More noticeable was the evolution of hair elongation, which slightly (+2.8%) but significantly increased after 84 days, leading to an enhancement compared with the placebo group.Furthermore, WPLC supplementation improved hair growth (+12.5%)compared with the placebo group after 84 days.

Effects of WPLC supplementation on clinically evaluated hair improvement
The percentage of participants showing improved clinical evaluation of hair density and volume at a time point (D56/D84) compared with D0 is presented in Table 5.A clinically relevant enhancement (>50%) of hair density was observed in the WPLC group at D56 and in both groups at D84.Similar results were obtained for hair volume.It should also be noted that there was a subset of participants showing worsened hair density/volume in the placebo group (density: 3%, volume: 9%), while no such worsening was observed in the WPLC group.

Effects of WPLC supplementation on scalp sebum content
In the whole cohort, scalp sebum content in the placebo group presented no evolution throughout the study while WPLC supplementation decreased it after 84 days, yet not leading to any significant difference with the placebo (data not shown).Participants with normal and dry hair are poorly relevant due to their low scalp sebum content, and indeed, they showed no variation in their scalp sebum content (data not shown).On the contrary, in the subpopulation of participants with oily hairs (baseline scalp sebum content ≥140 μg/cm 2 , Figure 4), WPLC supplementation decreased sebum content by −11.9% (p = 0.013) at D86, and this decrease was significant compared with the placebo (p = 0.044).

Effects of WPLC supplementation on hair characteristics of postmenopausal women
Focusing on the postmenopausal subgroup of participants, the effects of WPLC supplementation were similar to that observed in the entire population.As presented in Table 6, a significant decrease in telogen hair density and proportion was observed in the subgroup of postmenopausal women after 56 (−18.1% and −18.0%respectively) and 84 days (−22.8% and −26.6%  respectively) of supplementation, while no difference was observed in the placebo group over time.Similarly, a significant increase in anagen hair density and proportion was observed in this subgroup after 56 (+4.6% and + 4.7% respectively) and 84 days (+13.0%and +6.9% respectively) of supplementation, while no difference was observed in the placebo group over time.The variation of telogen/anagen hair density/proportion was therefore significantly different between WPLC and placebo groups, both at D56 and D84.It should be noted that no significant difference in density and proportion of hair in anagen/telogen phases was observed at baseline between premenopausal and postmenopausal women (data not shown).
Additionally, and similarly to that observed in the entire population, WPLC supplementation improved hair growth in postmenopausal women (+9.2%) after 84 days, in comparison with the placebo.While not reaching statistical significance, an upward trend in hair elongation was also observed in postmenopausal women supplemented with WPLC (+3.4%).Whatever the item, self-evaluation was consistently higher in the WPLC group than in the placebo group.This was particularly true for replies to questions such as 'Do you feel that…' '…your hair is less greasy', '…your hair grows faster', '…your hair quality improved', '…your hair has more volume' or '…you lose fewer hairs', confirming that participants also perceive clinical signs induced by WPLC supplementation.

DISCUSSION
Using acute TE as a clinical model of temporary hair loss, our results show a significant effect of WPLC in reducing hair loss and improving hair condition.Not only did it significantly reduce the density and proportion of telogen hair, leading to a proportion of telogen hair below that admitted to characterize excessive hair loss, but it also increased the density and proportion of anagen hair.Moreover, WPLC supplementation rapidly decreases the number of hairs tugged upon pull tests and leads to faster hair growth when analysing shaved scalp regions.Even if significant improvements were evidenced in the placebo group after 3 months (D84), they most likely correspond to the spontaneous recovery from acute TE.Other elements may be involved but, most importantly, WPLC supplementation enabled significantly faster and better enhancements of all these outcomes.Besides, if the supplement did not significantly change hair diameter, it did improve hair elongation and therefore resistance to breakage, clinically evaluated density/ volume, and the global perception of hair condition evaluated by participants.Additionally, WPLC proved efficient in reducing hair loss and improving hair reappearance and growth in postmenopausal women, at a similar level to that observed in the entire population.Interestingly, and in contrast with that observed in the whole cohort, no improvement was evidenced in the placebo group of postmenopausal women, suggesting that the natural recovery from acute TE is slower or less efficient in postmenopausal women.By accelerating this natural recovery, the supplementation with WPLC is therefore particularly suitable for postmenopausal women to reverse excessive hair loss.While the number of such studies is scarce, acute TE was previously demonstrated to be a relevant clinical model to evaluate the effectiveness of natural ingredients to reduce hair loss.In particular, wheat polar lipid-encapsulated miliacin, the main triterpenoid from millet (Panicum miliaceum) was proved to be efficient in reducing some telogen effluvium signs in a randomized, double-blind, placebo-controlled clinical study performed during 84 days [23].The supplementation decreased telogen hair density and improved clinically evaluated hair characteristics, but did not lead to any increase in the density of hairs in the anagen phase in comparison with the placebo.It was argued that such an absence of effect after 84 days is not surprising as it can take four to 7 months between the shedding of telogen hairs and the moment hairs grow sufficiently to become visible at the scalp surface [34].Yet, this hair eclipse phenomenon is not systematic and relates to some physiological or pathological conditions, which could make sense in the case of telogen effluvium.Still, teloptosis generally occurs late, and the club hair is retained until the emergence of a new shaft from the scalp surface.Therefore, it is possible to evidence a positive effect on anagen hair within a few weeks.This is the case upon WPLC supplementation.Furthermore, the increased hair growth induced by the supplement could have favoured a quicker visibility of emerging hairs.This is of interest as it implies that WPLC does not only have an anti-hair shedding effect but also stimulates hair reappearance and growth.Therefore, it seems that WPLC could promote the anagen phase while delaying the onset of the telogen phase.Similarly, a prospective clinical trial revealed the efficacy of a food supplement containing L-cystine, Serenoa repens and Equisetum arvense extracts, zinc and vitamins on hair loss associated with telogen effluvium in women [35].While the supplementation during 6 months with the blend showed a significant reduction in the number of hairs removed in the pull test, the study did not report any beneficial effect on hair growth.Additionally, a French pine bark extract, rich in proanthocyanidins, was recently reported to clinically improve total hair density in Chinese menopausal women following a 6-month supplementation, but without mentioning if the supplementation specifically improved anagen hair density and therefore hair growth [36].
To our knowledge, this is the first report of a clinical effect of sphingolipids on hair growth stimulation.Besides the effects of WPLC supplementation on hair loss, growth and condition, the present clinical evaluation also shows that WPLC decreased scalp sebum content in women with oily hair.How WPLC and its sphingolipids, especially glucosylceramides, and digalactosyl diglycerides (DGDG), can have such benefits will necessitate in vitro analyses to elucidate the underlying mechanisms.DGDG are a natural emulsifier which are likely to improve the efficacy of sphingolipids, especially glucosylceramides, by increasing intestinal absorption and bioavailability [25].Diet is a substantial source of sphingolipids humans must consume to obtain the ceramides and essential lipids they cannot synthesize [37].Several lines of evidence from animal studies indicate that nutritional glucosylceramides are metabolized by the gastrointestinal tract and enter the bloodstream to reach different organs, including the skin, where they serve as a source of ceramides [38][39][40].These ceramides account for 50% of the lipids from the skin's outermost layer, the stratum corneum, and are essential for its structure and function as a barrier.Several studies showed that ceramide dietary supplementation has beneficial effects on the skin barrier function, hydration, elasticity and recovery [25,26,[28][29][30]41].If these effects also apply to the scalp will need to be determined.Yet, similarly to the stratum corneum, ceramides are important components of intercellular lipids from the hair cuticle and are thought to exert a barrier function for hair against various external damages [42].Besides this structural function, our results highlight a potential role of sphingolipids, and glucosylceramides, on hair cycle regulation.

CONCLUSION
This pilot clinical study showed for the first time the beneficial effect of WPLC in reducing excessive hair shedding while stimulating the appearance and growth of new hairs, enabling a faster recovery.WPLC also improved participants' perception of their hair condition, which could have a positive psychological impact.Additionally, WPLC supplementation was associated with a reducing effect on scalp sebum content, which could be of general interest to women with oily hair.Furthermore, the beneficial effects of WPLC supplementation were evidenced in postmenopausal women at a similar level to that observed in the entire cohort.Together, these results highlight the promising use of WPLC as a nutricosmetic ingredient preventing hair loss and improving hair growth and quality in healthy women.These beneficial effects will need to be confirmed clinically and to be further investigated to identify the underlying mechanisms of action.

F I G U R E 1
Diagram of the study design.T A B L E 1 Composition of the WPLC and placebo capsules.

*T A B L E 2
Ages are reported as mean ± SEM. **Oily hair type is defined as women presenting a baseline scalp sebum content ≥140 μg/cm 2 .Descriptive statistics of the population at baseline (D0).F I G U R E 3 Evolution of parameters evaluated by phototrichograms.Results are presented as mean ± SEM with °p < 0.05, °°p < 0.01 and °°°p < 0.001 for the intra-group statistical significance versus D0, and *p < 0.05, **p < 0.01 and ***p < 0.001 for the inter-groups statistical significance.

T A B L E 3
Number of hairs tugged upon pull test.

Figure 5
Figure 5 presents the results from the 17-item questionnaire completed by participants at the end of the study (D84).Whatever the item, self-evaluation was consistently higher in the WPLC group than in the placebo group.This was particularly true for replies to questions such as 'Do you feel that…' '…your hair is less greasy', '…your hair grows faster', '…your hair quality improved', '…your hair has more volume' or '…you lose fewer hairs', confirming that participants also perceive clinical signs induced by WPLC supplementation.
Hair diameter, elongation and growth.Results are reported as mean ± SEM.In between brackets, is the intra-group significance of the evolution versus D0.Percentage of variation in scalp sebum content compared with D0 in women with oily hair.Results are presented as mean ± SEM with *p < 0.05 for the inter-groups statistical significance.
T A B L E 4Note: Evolution of hair parameters in the subgroup of postmenopausal women.Results are reported as mean ± SEM.In between brackets, is the intra-group significance of the evolution versus D0.
T A B L E 6Note: