nutrients
Article
A Collagen Supplement Improves Skin Hydration,
Elasticity, Roughness, and Density: Results of a
Randomized, Placebo-Controlled, Blind Study
Liane Bolke 1 , Gerrit Schlippe 1 , Joachim Gerß 2 and Werner Voss 1, *
1
2
*
Dermatest GmbH, Engelstraße 37, D-48143 Münster, Germany; dr.bolke@dermatest.de (L.B.);
dr.schlippe@dermatest.de (G.S.)
Institut für Biometrie und klinische Forschung (IBKF) der Westfälischen Wilhelms-Universität Münster,
Schmedding Straße 56, D-48149 Münster, Germany; joachim.gerss@ukmuenster.de
Correspondence: dr.voss@dermatest.de; Tel.: +49-251-481637-20
Received: 7 August 2019; Accepted: 8 October 2019; Published: 17 October 2019
Abstract: The purpose of this randomized, placebo-controlled, blind study was to investigate the
effects of the drinkable nutraceutical ELASTEN® (QUIRIS Healthcare, Gütersloh, Germany) on skin
aging and skin health. Drinking ampoules provides a blend of 2.5 g of collagen peptides, acerola
fruit extract, vitamin C, zinc, biotin, and a native vitamin E complex. This controlled interventional
trial was performed on 72 healthy women aged 35 years or older. They received either the food
supplement (n = 36) or a placebo (n = 36) for twelve weeks. A skin assessment was carried out and
based on objective validated methods, including corneometry (skin hydration), cutometry (elasticity),
the use of silicon skin replicas with optical 3D phase-shift rapid in-vivo measurements (PRIMOS)
(roughness), and skin sonography (density). The verum group was followed for an additional four
weeks (without intake of the test product) to evaluate the sustainability of the changes induced by
the intake of the test product. The test product significantly improved skin hydration, elasticity,
roughness, and density. The differences between the verum group and the placebo group were
statistically significant for all test parameters. These positive effects were substantially retained
during the follow-up. The measured effects were fully consistent with the subjective assessments of
the study participants. The nutraceutical was well tolerated.
Keywords: aging; beauty; bioavailability; collagen peptides; cutometry; corneometry; wrinkles; high
coverage [HC] collagen complex
1. Introduction
Healthy skin provides an active interface between the internal and external environments of
the body and enables permanent adaptation and acclimatization of an organism during its lifetime.
Many different factors exacerbate the aging process of the skin, including intrinsic ageing, irradiation,
consumption of a non-balanced diet, and stress-related deficiencies in micronutrients [1–3], leading to
an age-dependent collagen loss in the skin.
Collagen, the most abundant component of the extracellular matrix, is the decisive protein that
determines skin physiology, by maintaining the skin structure and enabling its numerous functions to
take place [4–6]. The extracellular matrix retains water and supports a smooth, firm, and strong skin.
The structure of collagen is reminiscent of a rope. Three chains wind around each other forming a
collagen triple helix. These building blocks combine to form collagen fibrils of enormous strength and
tensile force [4–6].
Studies have shown that age-dependent reduction in collagen synthesis can be reversed by oral
administration of specific bioactive collagen peptides [4,7–11]. These oligopeptides are obtained by
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enzymatic hydrolysis of natural collagen. After ingestion, they are further metabolized to bioactive
di- and tri-peptides in the gastrointestinal tract, which are then released into the blood stream and
accumulated in the skin to form the collagen biomatrix [4,7,9]. Typical collagen hydrolysates are
composed of peptides of different lengths and, depending on the collagen source, are characterized by
a special amino acid composition. The unique (high coverage—[HC]) collagen complex (ELASTEN® )
tested here contains short chain oligopeptides composed of 5 to 8, 9 to 15, and 16 to 26 amino acids and
have a high coverage with amino acids sequences found in human skin collagen proteins.
External and internal factors drive the physiological process of skin aging associated with a decline
in collagen formation [12,13]. The collagen content of young and healthy skin has been demonstrated
to exceed 75% [4–6,12,13]. Collagen fibers are synthesized primarily by the fibroblasts in the deeper
layers of the skin. As such, rejuvenation of the biomatrix can be effectively improved only through a
supply of sufficient nutrients via the blood stream [2]. Collagen formation is diminished in mature
skin and the biomatrix of the skin begins to collapse when the collagen scaffold loses its strength and
stability [5,7,9,14]. Factors such as sunlight, smoking, environmental pollution, alcohol abuse, and
nutrient deficiency can accelerate this process [12,13]. The elasticity is then diminished, and lines and
wrinkles emerge. Due to the loss of collagen, the skin becomes increasingly thinner and drier.
A previous pilot study demonstrated that the oral intake of special bioactive collagen peptides,
also tested in the present trial, induce beneficial effects on human skin structure and function [8]. In
this former non-controlled pilot trial, which was conducted in 16 healthy women, ELASTEN® was
orally applied for 3 months. The study showed significant and sustainable improvements of skin
hydration, elasticity, and roughness. The present study was performed to confirm the results obtained
in the pilot trial under randomized, placebo-controlled conditions. The peptides provided by the food
supplement ELASTEN® are characterized by a high contribution of amino acid sequences from human
collagen, and are combined with specific synergistically acting dermonutrients.
2. Materials and Methods
2.1. Study Design and Ethical Aspects
This clinical study employed a randomized, placebo-controlled, single-blind design. It was
conducted according to the applicable principles of good clinical practice (GCP) [15]. The clinical study
was registered in the German Clinical Trial Register and at the International Clinical Trials Registry
Platform (no. DRKS00015664). The investigation was in full compliance with the principles outlined in
the Declaration of Helsinki and with national regulations of Germany. A written informed consent
was received from all volunteers. The trial protocol was approved by the Freiburg Ethics Commission
International, Freiburg, Germany on 11 September 2017.
2.2. Study Participants
A total of 72 female subjects aged 35 years or more with healthy skin of any type participated in
this study. The main exclusion criteria were as follows: Major or chronic skin diseases, major internal or
chronic diseases, intake of drugs with any impact on skin reactions (e.g., glucocorticoids, antiallergics,
and topical immunomodulators), application of preparations and care products containing active
substances 7–10 days before participating in the study, heavy allergies or the occurrence of severe
adverse events due to cosmetics in the past, sunbathing or solarium visits during the study, known
cancer, pregnancy, and lactation.
Participants were instructed to maintain their living habits 9 and to not begin or change any
estrogen or progesterone therapies. However, none of the participants were under estrogen or
progesterone treatment during the study. Any intake of other products similar to the test product
during the study was not allowed.
The recruited subjects were randomized to receive either ELASTEN® (verum group) or a placebo.
Randomization was performed with alternating allocation of subjects.
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2.3. Study Schedule
The study duration was twelve weeks. After obtaining informed consent from the subjects, their
suitability for participation in the study was checked. Before the first intake of the study product,
after twelve weeks of intake, and after a follow-up period (without intake) of 4 weeks (T16), subjects
were dermatologically examined, and tolerability and efficacy data were collected. At the end of the
follow-up period, the sustainability of the previously observed effects was evaluated in the test group
of subjects who had taken the test product for the twelve-week period.
2.4. Test Product and Placebo
The test product is classified as a food supplement. Both the test product and placebo were
delivered in identical drinking ampoules. The test product ELASTEN® (QUIRIS Healthcare, Gütersloh,
Germany) contained a specially developed blend of 2.5 g collagen peptides, 666 mg acerola fruit
extract, 80 mg vitamin C, 3 mg zinc, 2.3 mg vitamin E, and 50 µg biotin. Other ingredients, which
were also contained in the placebo, were potassium sorbate, sodium benzoate, carboxymethylcellulose,
citric acid, natural aroma, and water. The placebo (QUIRIS Healthcare, Gütersloh, Germany) did not
contain any nutrients. The test product and placebo were taken daily before or together with a meal.
The specific collagen peptides were produced following GMP (good manufacturing practice) [16]
guidelines in an IFS (international featured standards)—and ISO (International Organization for
Standardization)—certified plant by water extraction of the endogenous collagen from bovine skin,
and subsequent enzymatic hydrolysis and sterilization.
2.5. Assessment of Safety and Tolerability
Safety and tolerability of the test material was assessed by three methods: (1) Evaluation of
tolerability by dermatological examinations before, during, and after the application phase of the
study; (2) monitoring of adverse events during the study through information collected in interviews
and questionnaires; and (3) the questionnaire at the end of the study.
2.6. Dermatological Examinations
Before, during, and after the study, the skin of subjects was examined according to established
clinical and dermatological assessment criteria. Each finding and type of reaction before and after the
study was documented and graded on a four-point scale: 0 = no pathological finding, 1 = mild skin
reaction, 2 = moderate skin reaction, and 3 = severe skin reaction.
2.7. Measurements
All measurements were done under rested conditions of the subjects and under stable physical
environmental conditions (room temperature 20 ◦ C and humidity 40%–60%).
2.7.1. Skin Hydration
Hydration of the external layer of the epidermis (stratum corneum) was measured on the forearm
capacitively with a Corneometer CM 825 (Courage and Khazaka, Cologne, Germany). For each
measurement time, at least three measurements at different locations in the test area on the forearm
were performed [17].
2.7.2. Skin Elasticity
For the assessment of skin elasticity, a Cutometer MPA 580 (Courage and Khazaka, Cologne,
Germany) was used. The functional principle is based on suction of the skin using a probe with
negative pressure, which causes the test area to be drawn into the aperture of the probe [18]. For each
measurement, skin elasticity (“R2”) at three different places of the test area (forearm) was assessed and
the values were averaged.
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2.7.3. Skin Roughness
Skin roughness was measured on the face of the subject, on the basis of silicone imprints (skin
replicas). The structure of the skin surface was determined by means of the optical 3D in-vivo measuring
method PRIMOS (phase-shift rapid in-vivo measurement of skin; PRIMOS Compact, GFMesstechnik
GmbH, Teltow, Germany). The “arithmetic average roughness” and the “maximum roughness” were
used as common skin surface descriptors. A replica was prepared for each measurement in order
to determine skin roughness Rz, which is defined as arithmetic mean of the individual depths of
five contiguous individual measuring sections of the (digitally) filtered profile of equal lengths. The
technology reproducibly determines skin roughness [19].
2.7.4. Skin Density
Sonographic measurements were used to determine skin density [14]. The SkinScanner DUB®
Simple (tpm® taberna pro medicum, Lüneburg, Germany) enables the visualization of structures up to
a maximal depth of 1 cm. Measurements were performed on the thigh.
2.8. Questionnaire
After 12 and 16 weeks, participants filled out questionnaires regarding their subjective assessments
of different parameters concerning the characteristics and performance of the product such as efficacy,
odor, taste, consistency, and skin appearance.
2.9. Statistical Analysis
Statistical analyses were performed according to the principles of ICH (International Conference
on Harmonization) guideline E9 “Statistical Principles for Clinical Trials” [20] using SAS software
(Version 9.4 for Windows, SAS Institute Inc., Cary, NC, USA).
The objective skin parameters—hydration, elasticity, roughness, and density—were evaluated
by descriptive analyses at T0 (day 0), T12 (day 84), and T16 (day 112). Efficacy was determined by
relative changes of these parameters, which were determined by the following differences of the
means: T12–T0, T16–T0, and T16–T12. The location and scale statistics of all the parameters were
calculated, including the arithmetical mean, standard deviation, minimum, and maximum. From the
calculated values of skewness and kurtosis it was concluded that all the parameters could be regarded
as (approximately) normally distributed.
The results are presented graphically by means of box-and-whisker plots. The box ranges from
the 25th percentile up to the 75th percentile. Whiskers are drawn from the ends of the boxes to the
largest and smallest values that did not represent outliers. Outliers are defined as being values more
than 1.5 times the interquartile range away from the box. Outliers are represented by symbols beyond
the whiskers.
Inferential statistical analyses were performed using Student’s t test [21]. Intra-individual mean
changes of skin parameters (comparing T12 versus T0, T16 versus T0, and T16 versus T12) were
evaluated using paired t tests. The mean outcomes in the verum and placebo groups were compared
using the t test for independent samples. The primary outcomes and test hypotheses of the trial
were based on the comparison of the verum and placebo groups with respect to the relative change
(T12–T0) of: (i) Skin hydration, (ii) skin elasticity, (iii) skin roughness, and (iv) skin density. The
multiple significance level across the four primary tests was set to 5% (two-sided). In order to adjust for
multiple testing, the Bonferroni method [22] was applied. The primary results provide confirmatory
statistical evidence. Beyond the primary statistical analyses, all other statistical analyses are considered
exploratory. The p-values are regarded noticeable (“significant”) for p ≤ 0.05.
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3. Results
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3.1. CONSORT (Consolidated Standards of Reporting Trials) Flow Diagram of the Controlled
Interventional
Trial
3.1. CONSORT (Consolidated Standards of Reporting Trials) Flow Diagram of the Controlled Interventional
Trial
Seventy-two subjects aged 35 to 73 years were statistically analyzed. The mean age in the verum
group (nSeventy-two
= 36) was 50.6
± 11.2
years
the placebo
group (n analyzed.
= 36), 52.4The
± 8.3
years.
subjects
subjects
aged
35 and
to 73inyears
were statistically
mean
age No
in the
had verum
to be excluded
the study.
group (n =during
36) wasscreening
50.6 ± 11.2 and
yearsthroughout
and in the placebo
groupNo
(n protocol
= 36), 52.4violations
± 8.3 years.occurred.
No
subjects had
to be for
excluded
during
screening
and throughout
study. the
No intention-to-treat
protocol violations (ITT)
All subjects
assessed
eligibility
could
be analyzed
(n = 72).theHence,
occurred.
All
subjects
assessed
for
eligibility
could
be
analyzed
(n
=
72).
Hence,
the intention-topopulation and the per-protocol (PP) population were identical. The safety population
(SP) also
treat
(ITT)
population
and
the
per-protocol
(PP)
population
were
identical.
The
safety
populationtrial is
included all 72 enrolled subjects. The flow of subjects through the controlled interventional
(SP) also included all 72 enrolled subjects. The flow of subjects through the controlled
depicted in a CONSORT conform diagram [23] (Figure 1).
interventional trial is depicted in a CONSORT conform diagram [23] (Figure 1).
Assessed for eligibility (n = 72)
Enrollment
Excluded (n = 0)
Randomized (n = 72)
Allocation
Allocated
to
ACTIVE
intervention
Allocated to PLACEBO intervention
(n = 36)
(n = 36)
Follow-Up
Lost to follow-up (n = 0)
Lost to follow-up (n = 0)
Discontinued intervention (n = 0)
Discontinued intervention (n = 0)
Analysis
Analyzed
(n = 36)
—Excluded from analysis (n = 0)
Analyzed
(n = 36)
—Excluded from analysis (n = 0)
Figure
1. Recruitmentofofthe
theeligible
eligible subjects
subjects with
protocol
and and
assessment.
Figure
1. Recruitment
withthe
theintervention
intervention
protocol
assessment.
clinical
study
wasconducted
conducted as
as aa two-arm
two-arm clinical
trialtrial
of the
The The
clinical
study
was
clinicalinterventional
interventional
of test
the product
test product
against placebo for twelve weeks with a follow-up period of four weeks without intake in the
against placebo for twelve weeks with a follow-up period of four weeks without intake in the subjects
subjects that received the test product. At the end of the follow-up period, the sustainability of the
that previously
received the
test product. At the end of the follow-up period, the sustainability of the previously
observed effects was demonstrated in the test group that was no longer treated with the
observed
effects All
wasenrolled
demonstrated
theexamined
test group
was before
no longer
theproduct
test product.
test product.
subjects in
were
as that
intended
first treated
intake ofwith
the test
All enrolled
subjects
were
examined
as
intended
before
first
intake
of
the
test
product
or
placebo
or placebo (T0), after twelve weeks of intake of test product or placebo (T12), and after a follow-up (T0),
afterperiod
twelve
weeksintake
of intake
ofweeks
test product
or that
placebo
(T12), andtaken
afterthe
a follow-up
without
of four
in subjects
had previously
test productperiod
(T16). without
intake of four weeks in subjects that had previously taken the test product (T16).
3.2. Tolerability
oughout
the study
follow-up
period. period.
throughout
theand
study
and follow-up
Skin3.3.
Hydration
Skin Hydration
Figure 2Figure
shows2 the
descriptive
analysisanalysis
of skin hydration
before intake
studyofproducts
(at
shows
the descriptive
of skin hydration
beforeof
intake
study products
(at
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6 of 14
, after
twelve
of
intake
T12),(atand
at the
of the
period (at
T16).(atNo
T0),
after weeks
twelve
weeks
of (at
intake
T12),
and end
at the
end follow-up
of the follow-up
period
T16). No
Nutrients
2019, 11,
2494
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nificant
differences
were found
the mean
skin
hydration
at T0 for
significant
differences
were
found
for
theinitial
mean
initial
skin
hydration
atthe
T0verum
for thegroup
verumand
group
and
The for
products
were
well
tolerated.
Dermatological
examinations
revealed
no pathological
skin
irritancy
or
tolerability
of
the hydration
testwas
product/placebo
was
placebo
group (35.0
± reactions,
4.8
AU
vs.
33.7 vs.
±reactions,
5.1
AU,
p =allergic
0.2405).
At T12,The
mean
skin
hydration
the placebo
group
(35.0
± 4.8
AU
33.7
± 5.1
AU,
p =reactions.
0.2405).
At
T12,
mean
skin
was
3.2.
Tolerability
rated
by
subjects
as
follows:
“very
good”
=
66%/56%,
“good”
=
33%/33%,
“neither
nor”
=
0%/8%,
nificantly
increased,
by 28.0%
11.5% ±(44.5
± 4.4
AU± vs.
± 5.7
AU,
p < AU,
0.0001),
in the verum
significantly
increased,
by± 28.0%
11.5%
(44.5
4.4 36.6
AU vs.
36.6
± 5.7
p < 0.0001),
in the verum
“bad”
=increase
0%/3%,
and
“very
bad”
=placebo
0%/0%. was
In
thelimited
placebo
group,
one
subject
reported
nausea and
up. On
the On
other
the
in
the
placebo
group
to
9.0%
±
6.6%.
group.
thehand,
other
hand,
the
increase
in
the
group
was
limited
to
9.0%
±The
6.6%.
The
The products were well tolerated. Dermatological examinations revealed
no pathological
skin
one
heartburn.
Apart
from
these
two
cases,
participants
did
not
report
any
adverse
erence
betweenbetween
the
groups
T12, as
well
difference
betweenbetween
the
relative
changes
in test
skinproduct/placebo
difference
the at
groups
atreactions,
T12, as the
well
as the difference
the relative
changes
in skin events was
reactions,
irritancy
or
allergic
reactions.
The
tolerability
of
the
throughout the study and follow-up period.
dration
of both groups
to
be highly
(p
< 0.0004)
favorin
offavor
the test
product.
hydration
of both
groups
proves
besignificant
highly
significant
(p66%/56%,
< in
0.0004)
of
the
test product.
ratedproves
by subjects
asto
follows:
“very
good”
=
“good”
= 33%/33%,
“neither nor” = 0%/8%,
The final
measurements
at
T16
show
that
such
effects
persist
for
some
time.
After
four
weeks
The
final“bad”
measurements
at
T16
show
that
such
effects
persist
for
some
time.
After
four weeks
= 0%/3%,
and “very bad” = 0%/0%. In the placebo group, one subject
reported
nausea and one
3.3.
Skin Hydration
houtwithout
further further
taking
of
the Apart
test
product,
skin
hydration
was stillwas
significantly
increased
inevents in
taking
of the
testthese
product,
skin participants
hydration
stillreport
significantly
increased
heartburn.
from
two
cases,
did
not
any
adverse
throughout the
Figure 2 shows the descriptive analysis of skin hydration before intake of study products (at
mparison
to the initial
(40.1
±
4.9
AU).
comparison
tostudy
thestate
initial
state
(40.1
±
4.9
AU).
and follow-up period.
T0), after twelve weeks of intake (at T12), and at the end of the follow-up period (at T16). No
significant
differences were found for the mean initial skin hydration at T0 for the verum group and
3.3. Skin
Hydration
the placebo group (35.0 ± 4.8 AU vs. 33.7 ± 5.1 AU, p = 0.2405). At T12, mean skin hydration was
Figure
2 shows the descriptive analysis of skin hydration before intake of study products (at T0),
significantly increased, by 28.0% ± 11.5% (44.5 ± 4.4 AU vs. 36.6 ± 5.7 AU, p < 0.0001), in the verum
after twelve
weeks
intake
(at the
T12),
and atinthe
end
of thegroup
follow-up
period to
(at9.0%
T16).± No
significant
group. On
the of
other
hand,
increase
the
placebo
was limited
6.6%.
The
differences
were
found
for
the
mean
initial
skin
hydration
at
T0
for
the
verum
group
and
the
placebo
difference between the groups at T12, as well as the difference between the relative changes in skin
grouphydration
(35.0 ± 4.8
AU groups
vs. 33.7proves
± 5.1to
AU,
p = 0.2405).
At T12,
mean in
skin
hydration
significantly
of both
be highly
significant
(p < 0.0004)
favor
of the testwas
product.
final measurements
that
such
effects
for some
After four
weeks
increased,The
by 28.0%
± 11.5% (44.5at±T16
4.4 show
AU vs.
36.6
± 5.7
AU,persist
p < 0.0001),
in time.
the verum
group.
On the
further
taking
of placebo
the test group
product,
skin
hydration
was
still significantly
increased
in the
other without
hand, the
increase
in the
was
limited
to 9.0%
± 6.6%.
The difference
between
comparison
to
the
initial
state
(40.1
±
4.9
AU).
groups at T12, as well as the difference between the relative changes in skin hydration of both groups
proves to be highly significant (p < 0.0004) in favor of the test product.
Figure 2.Figure
Skin hydration
before (T0)
and (T0)
afterand
(T12)
intake
ofintake
study of
products,
as well asasafter
2. Skin hydration
before
after
(T12)
study products,
wellfollowas after followup (at T16)
and
placebo
boxplot
the
meanthe
(×),mean (×),
up for
(at the
T16)test
forproduct
the test (grey)
product
(grey)
and (white)
placebogroups.
(white) The
groups.
The shows
boxplot
shows
FigureFigure
2. Skin
hydration
before
(T0)(T0)
andand
after
(T12)
as well
wellasasafter
afterfollowfollow-up
2. Skin
hydration
before
after
(T12)intake
intakeofofstudy
study products,
products, as
(at T16)
for
the
test
product
(grey)
and
placebo
(white)
groups.
The
boxplot
shows
the
mean
(×),
median
up (at T16) for the test product (grey) and placebo (white) groups. The boxplot shows the mean (×),
median (median (
median
( max–min
),whiskers
and max–min
AUindicates
indicates
arbitrary arbitrary
absolute levels and
max–min
(
).).AU
arbitrary
units,where
), and
whiskers
(). AU( indicates
).arbitrary
AU indicates
units,
(), and),
and
max–min
whiskers
(whiskers
units, units,
where
absolute
levels and changes
changes are significantly different for the test product and placebo with p ≤ 0.0001 (****).
are significantly different for the test product and placebo with p ≤ 0.0001 (****).
3.4. Skin Elasticity
The final measurements at T16 show that such effects persist for some time. After four weeks
At T0, taking
skin elasticity
wasproduct,
similar inskin
the verum
group
(R2
= 0.69
± 0.05) andincreased
placebo group
(R2 =
without further
of the test
hydration
was
still
significantly
in comparison
0.71
±
0.06;
p
=
0.3240).
After
intake
of
the
test
product
and
placebo,
the
elasticity
(R2
values)
to the initial state (40.1 ± 4.9 AU).
significantly increased in both groups (Figure 3). At T12, skin elasticity was increased in the verum
3.4. Skin
Elasticity
group
by 0.81 ± 0.04 AU and in the placebo group by 0.75 ± 0.06 AU. This difference proved to be
highly
significant
(p < 0.0004).
At
T0, statistically
skin elasticity
was similar
in the verum group (R2 = 0.69 ± 0.05) and placebo group
(R2 = 0.71 ± 0.06; p = 0.3240). After intake of the test product and placebo, the elasticity (R2 values)
significantly increased in both groups (Figure 3). At T12, skin elasticity was increased in the verum
group by 0.81 ± 0.04 AU and in the placebo group by 0.75 ± 0.06 AU. This difference proved to be
highly statistically significant (p < 0.0004).
Furthermore, skin elasticity in the test group was only slightly reduced at the end of the follow-up
period (R2 = 0.76 ± 0.07), corresponding to a mean decline of −6.38% ± 7.01%, however it did not drop
to its initial level.
Nutrients FOR PEER REVIEW
7 of 14
Nutrients 2019, 11, 2494
7 of 14
Nutrients FOR PEER REVIEW
ER REVIEW
6 of 14
The products were well tolerated. Dermatolo
reactions,
irritancy reactions, or allergic reactions.
ucts were well tolerated. Dermatological examinations revealed no pathological skin
rated
by
subjects
as follows: “very good” = 66%/5
ancy reactions, or allergic reactions. The tolerability of the test product/placebo was
“bad” = 0%/3%, and “very bad” = 0%/0%. In the
ects as follows: “very good” = 66%/56%, “good” = 33%/33%, “neither nor” = 0%/8%,
one heartburn. Apart from these two cases, p
%, and “very bad” = 0%/0%. In the placebo group, one subject reported nausea and
throughout the study and follow-up period.
n. Apart from these two cases, participants did not report any adverse events
e study and follow-up period.
3.3. Skin Hydration
ation
Figure 2 shows the descriptive analysis of sk
Figure 2.
Skin hydration
before (T0)
and(T0)
after
(T12)
intake
studyofproducts,
as well as
followFigure
2. Skin hydration
before
and
after
(T12)ofintake
study products,
as after
wellT0),
as
after
followafter
twelve weeks of intake (at T12), and a
shows the descriptive analysis of skin hydration before intake of study products (at
up (at T16)
forT16)
the test
(grey) and
placebo
(white) groups.
The boxplot
shows the
mean
(×),
up (at
for product
the test product
(grey)
and placebo
(white) groups.
The boxplot
shows
the
mean (×),
significant
differences were found for the mean ini
lve weeks of intake (at T12), and at the end of the follow-up period (at T16). No
the placebo group (35.0 ± 4.8 AU vs. 33.7 ± 5.1 A
ferences were found for the mean initial skin hydration at T0 for the verum group and
significantly increased, by 28.0% ± 11.5% (44.5 ± 4
roup (35.0 ± 4.8 AU vs. 33.7 ± 5.1 AU, p = 0.2405). At T12, mean skin hydration was
group. On the other hand, the increase in the p
ncreased, by 28.0% ± 11.5% (44.5 ± 4.4 AU vs. 36.6 ± 5.7 AU, p < 0.0001), in the verum
difference between the groups at T12, as well as th
e other hand, the increase in the placebo group was limited to 9.0% ± 6.6%. The
hydration
both
groups (at
proves to be highly signi
Figure
3. Skin
elasticity
beforebetween
(T0) and the
afterrelative
(T12) intake
of study
products,
andof
after
follow-up
ween the groups at T12,
as well
as3.the
changes
in skin
Figure
Skindifference
elasticity before
(T0) and after
(T12) intake
of study
products, and after follow-up (at
The the
final
measurements
T16)
for the
test product (grey)
and placebo
(white)
groups.
The boxplot shows
mean
(×), median at T16 show that suc
both groups proves to be
highly
< 0.0004)
favor
of the
test product.
T16)significant
for the test (p
product
(grey)inand
placebo
(white)
groups. The boxplot shows the mean (×),
without
further
taking
of the test product, skin
median median
(
), and
max–min
( ( whiskers
).).AU
indicates
arbitrary
units,
( T16 (show
), and
whiskers
(). The
).levels
AU
indicates
arbitrary
units,
( max–min
),whiskers
andwhiskers
max–min
( absolute
The
absolute
levels
and
changes
are
significantly
different
measurements
at
that
such
effects
persist
for
some
time.
After
four
weeks
),median
and
max–min
and
changes
are significantly
different
for the
comparison
to
the
initial
state
(40.1 ± 4.9 AU).
for theskin
test product
and
placebo
groups,
with p (****).
≤ 0.0001 increased
(****).
er taking of the test test
product,
hydration
was
still
in
product
and
placebo
groups,
with
p ≤significantly
0.0001
o the initial state (40.1 ± 4.9 AU).
Furthermore, skin elasticity in the test group was only slightly reduced at the end of the
3.5. Skin Roughness
(R2 = 0.76 ± 0.07), corresponding to a mean decline of −6.38% ± 7.01%, however it
Infollow-up
line withperiod
improvements
in skin hydration and elasticity, skin roughness decreased during
did not drop to its initial level.
intake of the test product. As shown in Figure 4, the depth of wrinkles measured by PRIMOS replicas
was reduced
the verum group after twelve weeks of intake. Starting from similar initial mean
3.5. Skin in
Roughness
values of 161.6 ± 11.4 µm (test product) and 161.7 ± 13.0 µm (placebo; p = 0.9702), the wrinkle depth
In line with improvements in skin hydration and elasticity, skin roughness decreased during
decreased to 118 ± 16.4 µm in the verum group and to 151.4 ± 15.9 µm in the placebo group. The
intake of the test product. As shown in Figure 4, the depth of wrinkles measured by PRIMOS
relative
difference
between
T0 and T12 was four times higher in the verum group (−26.8% ± 8.1%)
replicas
was PEER
reduced
in the verum group after twelve weeks of intake. Starting from similar initial
Nutrients FOR
REVIEW
8 of 14
than inmean
the placebo
group
(−6.4%
± (test
5.8%;
p < 0.0004).
The±maximum
improvement
of skin
roughness
values of 161.6 ± 11.4 µ m
product)
and 161.7
13.0 µ m (placebo;
p = 0.9702),
the wrinkle
was 41%.
depth decreased to 118 ± 16.4 µ m in the verum group and to 151.4 ± 15.9 µ m in the placebo group.
The relative difference between T0 and T12 was four times higher in the verum group (−26.8% ±
8.1%) than in the placebo group (−6.4% ± 5.8%; p < 0.0004). The maximum improvement of skin
roughness was 41%.
After the follow-up period, the depth of wrinkles increased between T12 and T16 from 118 ±
16.4 µm to 131.6 ± 21.9 µm, demonstrating a persistent, highly significant difference of −18.9% ±
9.9% in skin roughness in relation to the initial state (Figure 4; p < 0.0001).
Skin hydration before (T0) and after (T12) intake of study products, as well as after follow) for the test product (grey) and placebo (white) groups. The boxplot shows the mean (×),
Figure 2. Skin hydration before (T0) and after (T12
up (at T16) for the test product (grey) and placebo
Figure Figure
4. Skin roughness
(wrinkle (wrinkle
depth determined
from the phase-shift
rapid in-vivo
measurement
4. Skin roughness
depth determined
from the phase-shift
rapid
in-vivo
of skin measurement
(PRIMOS) skin
before (T0)
after
(T12)(T0)
intake
study
products
and
afterproducts
follow-up
of replica)
skin (PRIMOS)
skin and
replica)
before
andofafter
(T12)
intake of
study
and after follow-up (FU) with test product (grey) and placebo (white), boxplot showing the mean ), and max–min whiskers (
), and
(×), median ( ), and max-min whiskers ( ), absolute levels and changes are significantly different
O represent
), and max–min
whiskers
( product
). AU
indicates
arbitrary
units,
forwhiskers
the test
and placebo
at p and
< 0.0001
(****).are
outlier.
max-min
(
), absolute
levels
changes
significantly
different for the test product and
median
(
(FU) with test product (grey) and placebo (white), boxplot showing the mean
(×), median
(
placebo at p < 0.0001 (****).
3.6. Skin Density
O
represent outlier.
Both test product and placebo induced an improvement in the skin density, sonographically
measurable as the thickness of the epidermis. Starting from similar initial values (35.7 ± 7.2 µ m for
the test product and 36.9 ± 8.6 µ m for placebo), measurements revealed a highly significant increase
in the thickness of the epidermis and the corresponding skin density in the verum group by 24.8% ±
T0), after twelve
weeks
of intake
and
the end
(at T16).
No(at T16). No
T0), after
twelve
weeks(atofT12),
intake
(atatT12),
and of
at the
the follow-up
end of theperiod
follow-up
period
significant differences
found for
thefound
meanfor
initial
skin hydration
T0 for theat
verum
and group and
significantwere
differences
were
the mean
initial skinathydration
T0 forgroup
the verum
the placebo the
group
(35.0 group
± 4.8 AU
vs.± 33.7
± 5.1vs.AU,
0.2405).
mean
placebo
(35.0
4.8 AU
33.7p ±= 5.1
AU, At
p = T12,
0.2405).
Atskin
T12,hydration
mean skinwas
hydration was
significantlysignificantly
increased, by
28.0% ± 11.5%
(44.5± ±11.5%
4.4 AU
vs.±36.6
± 5.7vs.
AU,
p <± 0.0001),
verumin the verum
increased,
by 28.0%
(44.5
4.4 AU
36.6
5.7 AU, in
p <the
0.0001),
group.Nutrients
On the
other2494
hand,
the increase
in increase
the placebo
group
was group
limitedwas
to 9.0%
± 6.6%.
The±8 6.6%.
group.
the other
hand, the
in the
placebo
limited
to 9.0%
2019, 11,On
of 14 The
difference between
the
groups
at
T12,
as
well
as
the
difference
between
the
relative
changes
in
skin
difference between the groups at T12, as well as the difference between the relative changes in skin
hydration ofhydration
both groups
proves
to beproves
highly to
significant
< 0.0004) in
of the
product.
of both
groups
be highly(psignificant
(p favor
< 0.0004)
in test
favor
of the test product.
After
the final
follow-up
period,
depth
of that
wrinkles
increased
between
T12
and
T16 four
fromweeks
The final
measurements
at T16
showthe
such
effects
persist
for some
time.
four
weeks
The
measurements
atthat
T16
show
such
effects
persist
for After
some
time.
After
118
±
16.4
µm
to
131.6
±
21.9
µm,
demonstrating
a
persistent,
highly
significant
difference
of
without further
taking
of the
test of
product,
skin
hydration
still significantly
increased inincreased
without
further
taking
the test
product,
skin was
hydration
was still significantly
in
−18.9%
9.9%
in skin
roughness
relation
to AU).
the initial state (Figure 4; p < 0.0001).
comparison
to±the
initial
state
(40.1
4.9inAU).
comparison
to
the
initial± state
(40.1 ± 4.9
3.6. Skin Density
Both test product and placebo induced an improvement in the skin density, sonographically
measurable as the thickness of the epidermis. Starting from similar initial values (35.7 ± 7.2 µm for the
test product and 36.9 ± 8.6 µm for placebo), measurements revealed a highly significant increase in the
thickness of the epidermis and the corresponding skin density in the verum group by 24.8% ± 16.8%
(toNutrients
44.0 ±FOR
7.6 µm,
p < 0.0001; Figure 5). Furthermore, a significant improvement was observed in9the
PEER REVIEW
of 14
placebo group of 6.8% ± 14.8% (to 39.0 ± 8.7 µm, p < 0.0109). The difference between the relative
changes of both groups proved to be highly significant (p < 0.0004) in favor of the test product.
Figure 2. SkinFigure
hydration
before
(T0) and
after(T0)
(T12)
intake
study
products,
as well
as after
2. Skin
hydration
before
and
afterof(T12)
intake
of study
products,
asfollowwell as after followup (at T16) forup
the
product
and placebo
groups.
The boxplot
the mean
(×), the mean (×),
(attest
T16)
for the(grey)
test product
(grey)(white)
and placebo
(white)
groups.shows
The boxplot
shows
Figure 5. Skin density (sonographically measured) before (T0) and after (T12) intake of study products,
Figure
5. Skin density
measured)
(T0)
and groups.
after (T12)
study
and
after follow-up
(at T16)(sonographically
for the test product
(grey) andbefore
placebo
(white)
The intake
boxplotofshows
and
follow-up
(at
T16)
for
test product
(grey)
and). AU
placebo
(white)
groups. The
medianthe
(products,
), and
whiskers
( the
). AU
indicates
arbitrary
units,
median
( after
), and
max–min
whiskers
indicates
arbitrary
mean
(×), median
( max–min
), max–min
whiskers
(
), and( outliers
(o). Absolute
levels
and
changesunits,
are
boxplot shows the mean (×), median ( ), max–min whiskers ( ), and outliers (o). Absolute levels
significantly different for the test product and placebo with p ≤ 0.0001 (****), p ≤ 0.001 (***), and p ≤ 0.05
and changes are significantly different for the test product and placebo with p ≤ 0.0001 (****), p ≤
(*). O represent outlier.
0.001 (***), and p ≤ 0.05 (*). O represent outlier.
The effect of the test product within twelve weeks did not disappear during the four weeks
3.7.
Skin Improvements
of thePersistence
follow-upofperiod.
After discontinuing the application, the mean skin density decreased to
36.7 ± The
6.9 µm
at
T16.
This
value
was still
highly
significantly
increase
compared
to the initial
value at 6
efficacy and sustainability
ofathe
effects
of the test
product
are summarized
in Figures
T0and
(p =7.0.0008).
In Figure 6, the differences between the changes (T0–T12) in skin hydration (A), skin
Change from Baseline (%)
elasticity (B), skin roughness (C), and skin density (D) of the test product and placebo are
3.7. Persistence of Skin Improvements
illustrated. The relative differences between T0 and T12 were significantly higher in the verum
group
in the
placebo
group (p
0.0004).
Thethan
efficacy
and
sustainability
of<the
effects of the test product are summarized in Figures 6 and 7.
In Figure 6, the differences between the changes (T0–T12) in skin hydration (A), skin elasticity (B),
skin roughness (C), andA.
skin density (D) of the
placebo are illustrated.
B. test product andC.
D. The relative
differences between
T0
and
T12
were
significantly
higher
in
the
verum
group
than
in
the
placebo group
Skin Hydration
Skin Elasticity
Skin Roughness
Skin Density
(p < 0.0004).
30
20
10
0
-10
-20
-30
3.7. Persistence of Skin Improvements
Change from Baseline (%)
The efficacy and sustainability of the effects of the test product are summarized in Figures 6
and 7. In Figure 6, the differences between the changes (T0–T12) in skin hydration (A), skin
elasticity (B), skin roughness (C), and skin density (D) of the test product and placebo are
illustrated.
The relative differences between T0 and T12 were significantly higher in the verum
Nutrients
2019, 11, 2494
9 of 14
group than in the placebo group (p < 0.0004).
A.
Skin Hydration
B.
Skin Elasticity
C.
Skin Roughness
D.
Skin Density
30
20
10
0
-10
Nutrients FOR PEER REVIEW
10 of 14
-20
After
-30discontinuation of administration of the test product, the effect on skin hydration was
reduced by −45.8% during the follow up compared to T12. A better persistence was demonstrated
for the improvement of skin roughness. This parameter decreased by only 30.6% compared to T12.
Test Product: T0–T12
Skin elasticity and skin density were reduced by 38.5% and 31.3%, respectively (Figure 7). For all
Placebo: T0–T12
skin parameters tested in this study, the percentage improvements in the verum group at the end of
Figure
6.period
Percentage
of7)
skin
parameters
between
the baseline
andthe
theimprovements
the twelve
the
follow-up
(T16,change
Figure
were
much
more
pronounced
than
in the
Figure
6. Percentage
change
of skin
parameters
between
the
baseline
and
the
end
ofend
theof
twelve
week
week
interventional
period
(T0–T12)
in
the
test
group
(blue
bars)
and
in
the
placebo
group
(red
placebo
group at
T12 (Figure
interventional
period
(T0–T12)6).in the test group (blue bars) and in the placebo group (red bars). Error
bars). Error bars indicate the standard errors of the mean. Changes are significant at p < 0.0001 (all
bars indicate the standard errors of the mean. Changes are significant at p < 0.0001 (all parameters
parameters
except skin density at T16 with a significance level of p < 0.0008).
3.8.
Subjective
Rating
except
skin density
at T16 with a significance level of p < 0.0008).
Change from Baseline (%)
A.
Skin Hydration
B.
Skin Elasticity
C.
Skin Roughness
D.
Skin Density
30
20
10
12
12
16
12
16
16
0
-10
16
-20
-30
12
12 after 12 week Intervention: T0–T12
16 after 12 week Intervention and 4 week Follow up: T0–T16
Figure 7. Percentage changes of skin parameters in the test group between baseline and the end of the
Figure 7. Percentage changes of skin parameters in the test group between baseline and the end of
twelve week interventional period (T0–T12, solid blue bars) and between baseline and the end of the
the twelve week interventional period (T0–T12, solid blue bars) and between baseline and the end of
fourthe
week
periodperiod
(T0–T16,
open open
whitewhite
bars)bars)
for skin
hydration
(A), (A),
skinskin
elasticity
(B),(B),
skin
fourfollow-up
week follow-up
(T0–T16,
for skin
hydration
elasticity
roughness
(C),
and
skin
density
(D)
in
the
test
group.
The
error
bars
indicate
standard
errors
of
the
skin roughness (C), and skin density (D) in the test group. The error bars indicate standard errors of
mean.
Changes
are
significant
at
p
<
0.0001.
the mean. Changes are significant at p < 0.0001.
After
discontinuation
of administration
of the test
product, the
effect
hydration
was
In the
beginning, about
64% of all participants
characterized
their
skinonasskin
more
or less dry,
reduced
by −45.8%
during
the follow
up compared
to T12.
A better
persistence
demonstrated
approximately
22%
as normal,
and about
6% as fatty
(8% did
not provide
such was
information).
All
for prompted
the improvement
of
skin
roughness.
This
parameter
decreased
by
only
30.6%
compared
to
T12.
effects were more positively assessed by the test group as compared to the placebo
Skin
elasticity
and
skin
density
were
reduced
by
38.5%
and
31.3%,
respectively
(Figure
7).
For
all
skin
group. Up to three quarters of subjects in the test group agreed with the positive statements. As
parameters
the percentage
in the
verum
group
at the
endmost
of the
shown intested
Tablein1,this
the study,
differences
of the testimprovements
group compared
to the
placebo
group
were
follow-up
period
(T16,scaly
Figure
7) (47%
were more
muchagreements),
more pronounced
than the(23%),
improvements
in the (29%),
placebo
apparent
regarding
skin
skin elasticity
skin appearance
andatskin
(13%). After discontinuation of taking the study products, experienced effects
group
T12dryness
(Figure 6).
largely persisted for at least four weeks in both study groups.
Table 1. Self-perception rating, agreement to statements concerning test product effects reported as
a percentage in relation to placebo effects.
After 12 Weeks of Taking the Product
my skin is less dry.
my skin is less scaly.
the elasticity of my skin is improved.
my skin appearance is improved.
 (%) Test Group Relative to Placebo Group
+13.0
+47.4
+22.7
+28.6
Nutrients 2019, 11, 2494
10 of 14
3.8. Subjective Rating
In the beginning, about 64% of all participants characterized their skin as more or less dry,
approximately 22% as normal, and about 6% as fatty (8% did not provide such information). All
prompted effects were more positively assessed by the test group as compared to the placebo group.
Up to three quarters of subjects in the test group agreed with the positive statements. As shown in
Table 1, the differences of the test group compared to the placebo group were most apparent regarding
scaly skin (47% more agreements), skin elasticity (23%), skin appearance (29%), and skin dryness (13%).
After discontinuation of taking the study products, experienced effects largely persisted for at least
four weeks in both study groups.
Table 1. Self-perception rating, agreement to statements concerning test product effects reported as a
percentage in relation to placebo effects.
After 12 Weeks of Taking the Product
∆ (%) Test Group Relative to Placebo Group
my skin is less dry.
my skin is less scaly.
the elasticity of my skin is improved.
my skin appearance is improved.
my skin appears more wrinkle-free.
external skin care products can be used less frequently.
+13.0
+47.4
+22.7
+28.6
+10.5
+27.3
∆ = Delta, difference in percent after 12 weeks of intake.
4. Discussion
Topically applied skin care products such as creams, lotions, and sera often fail to reach the
deeper layers of the skin in order to causally and lastingly influence the skin aging processes. The
aim to reach the dermis, the most important skin layer for the restoration of collagen synthesis, has
been achieved by developing highly bioavailable and thus bioactive short chain nutritional collagen
peptides [4,5,10,24]. This was also confirmed by the present trial, particularly by the improvement of
the density and elasticity of the skin. It was clearly shown that the effects of the test product were not
restricted to the epidermis.
A systematic review of the dermatological applications of oral collagen supplementation has
recently demonstrated that collagen supplements can increase skin hydration, elasticity, and dermal
collagen density. Eleven studies with a total of 805 patients suggest that administration of collagen
peptides can positively impact various skin conditions and skin aging [9]. Collagen supplementation
was safe with no reported adverse effects. Asserin et al. demonstrated in a randomized controlled
trial that the intake of 10 g of collagen hydrolysate over at least 56 days leads to an increase in skin
moisture and collagen density compared to placebo [25]. Collagen dipeptides that were taken over
56 days in a study by Inoue et al. also resulted in significantly more improvement in skin moisture,
elasticity, wrinkles, and roughness for the subjects that received 10 mg per day in comparison to study
participants who received 0.5 mg per day or placebo [26].
Compared to placebo, a significant reduction in eye wrinkle volume along with an increase of
procollagen type I and elastin was reported by Proksch et al. after the intake of 2.5 g collagen per
day over 56 days [27,28]. In addition, it was shown by Schunck et al. the intake of 2.5 g collagen
peptides over a period of 180 days led to a statistically significant decrease in the degree of cellulite
and a reduced skin waviness on thighs [29].
The supplement tested here provides a drinkable blend of collagen peptides and acerola fruit extract
with endogenous antioxidants, such as vitamin C, zinc, biotin, and a native vitamin E complex. Studies
suggest that an age-related reduction in collagen synthesis can be addressed by the administration of
oral collagen peptides together with other specific skin nutrients [7,9,11].
Nutrients 2019, 11, 2494
11 of 14
A clinical pilot study has previously demonstrated significant effects of the test product on skin
hydration, elasticity, and roughness after three months of application of the supplement in 16 women
aged 45–60 years [8].
The present study was conducted as a clinical interventional study on 72 healthy women treated
either with the food supplement (n = 36) or a placebo (n = 36) for three months to confirm and
extend these observations. It was demonstrated that drinkable collagen peptides together with other
dermonutrients could induce long lasting visible improvements in the skin’s appearance. However, it
should also be considered that collagen peptides, depending on the source material and manufacturing
process, could differ with respect to molecular size and amino acid composition.
One reason for the significant improvements of skin parameters shown in the present study might
be the high similarity between the collagen peptides provided by the bovine [HC] collagen complex
and those of human collagen. Hydrolysis of the bovine collagen yields specific bioactive short chain
peptides that are characterized by a high coverage of their amino acid profile with the amino acid
sequence of human collagen I. The amino acid sequence coverage of the bovine collagen peptides
used in this study was determined by liquid chromatography–mass spectrometry (nanoLC/MS/MS
hardware [24]: Aquity® UPCL M-Class HSS T3, Waters, MA, USA) using Mascot software (Matrix
Science, London, UK). This analysis revealed a coverage of 31% for collagen type I alpha 1 chains, 18%
for collagen type I alpha 2 chains, and 13% for collagen type III alpha 1 chains. These values were
compared to 4% to 20%, 7% to 16%, and 6% to 11% ranges, respectively, for other collagen peptides,
obtained from pigs, chickens, or marine sources (see Reference [30] for a review).
Moreover, the amino acid composition of the peptides is reflected by a high content of specific
amino acids that are abundant building blocks of human collagen, such as hydroxyproline, proline,
glycine, glutamic acid, alanine, and arginine [7,31,32]. During digestion, the oligopeptides are further
metabolized to bioactive di- and tri-peptides in the gastrointestinal tract and are subsequently released
into the blood stream [11,33–38]. The concentration and type of collagen, as well as the content of
other skin-relevant nutrients can differ in mono and combination products. Therefore, it is crucial to
underline the importance of product-specific trials.
In the follow-up phase, the verum group was observed one month after cessation of the treatment
to evaluate the sustainability of the changes induced by the application. The results show that all the
effects were substantially retained during the follow-up period. Throughout the study, there were no
adverse effects, neither for the placebo nor for the test product, which has been on the market for many
years as a food supplement.
The placebo effects shown here were attributed to the unconscious lifestyle changes of the subjects
during the study and conclusively demonstrated the necessity of a placebo control to reliably assess
the effects of a test product. The differences between the verum group and the placebo group were
highly significant for all of the test parameters after three months of treatment. For all of the skin
parameters tested in this study, the percentage improvement in the verum group was still higher at the
end of the follow-up period, after four months, than at the beginning of the application.
The findings were relevant in terms of skin physiology and decisive for demonstrating the validity
of this specific approach. Moreover, the effects were not only fully confirmed in objective test methods
for assessing skin hydration, elasticity, roughness, and density, but also in the subjective assessment of
the subjects. Therefore, the oral application of dermonutrients allows for a long-lasting regeneration of
the skin that is clearly visible and cosmetically relevant.
5. Conclusions
This randomized, placebo-controlled clinical trial confirmed that skin aging could be addressed
using nutrients that are able to restore skin hydration, elasticity, and density. Objective dermatological
measurements, such as cutometry and corneometry, have proven that oral collagen peptides together
with other dermonutrients significantly improve skin hydration, elasticity, roughness, and density
after three months of intake. These tests thus verify the results obtained in previous trials. Moreover,
Nutrients 2019, 11, 2494
12 of 14
and in line with the objective measurements, the study participants, in their subjective assessments,
concluded that their skin appearance had significantly improved.
Finally, the collagen supplement did not cause any side effects and proved to be safe and well
tolerated during the entire period of application and thereafter.
Since the collagen peptides and the skin nutrients were taken orally, the effects reached the deeper
layers of the skin and sustainably improved skin physiology and appearance. In conclusion, the tested
dermonutrient allowed for a long-lasting and cosmetically relevant regeneration of the skin. Ongoing
studies are exploring the decisive nutritional mechanisms involved in improving skin physiology
and appearance.
Author Contributions: Conceptualization, L.B., G.S., and W.V.; methodology, L.B., G.S., and J.G.; validation, L.B.
and J.G.; formal analysis, J.G.; investigation, G.S. and L.B.; data curation, J.G.; draft writing—review and editing,
L.B., G.S., J.G., and W.V.; visualization, J.G.; supervision, W.V.; and project administration, L.B.
Funding: This research was funded by Quiris Healthcare, Germany.
Conflicts of Interest: The authors declare no conflict of interest. The sponsor had no influence on execution,
analysis and interpretation of the data.
References
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
Blume-Peytavi, U.; Kottner, J.; Sterry, W.; Hodin, M.W.; Griffiths, T.W.; Watson, R.E.; Hay, R.J.; Griffiths, C.E.
Age-Associated Skin Conditions and Diseases: Current Perspectives and Future Options. Gerontology 2016,
56 (Suppl. 2), S230–S242. [CrossRef]
Perez-Sanchez, A.; Barrajon-Catalan, E.; Herranz-Lopez, M.; Micol, V. Nutraceuticals for Skin Care:
A Comprehensive Review of Human Clinical Studies. Nutrients 2018, 10, 403. [CrossRef] [PubMed]
Zhang, S.; Duan, E. Fighting against Skin Aging: The Way from Bench to Bedside. Cell Transpl. 2018, 27,
729–738. [CrossRef] [PubMed]
Sato, K. The Presence of Food-Derived Collagen Peptides in Human Body-Structure and Biological Activity.
Food Funct. 2017, 8, 4325–4330. [CrossRef] [PubMed]
Cole, M.A.; Quan, T.; Voorhees, J.J.; Fisher, G.J. Extracellular Matrix Regulation of Fibroblast Function:
Redefining Our Perspective on Skin Aging. J. Cell Commun. Signal. 2018, 12, 35–43. [CrossRef]
Arseni, L.; Lombardi, A.; Orioli, D. From Structure to Phenotype: Impact of Collagen Alterations on Human
Health. Int. J. Mol. Sci. 2018, 19, 407. [CrossRef]
Zague, V.; de Freitas, V.; da Costa Rosa, M.; de Castro, G.A.; Jaeger, R.G.; Machado-Santelli, G.M. Collagen
Hydrolysate Intake Increases Skin Collagen Expression and Suppresses Matrix Metalloproteinase 2 Activity.
J. Med. Food 2011, 14, 618–624. [CrossRef]
Schlippe, G.; Bolke, L.; Voss, W. Einfluss oraler Einnahme von Kollagen-Peptiden auf relevante Parameter
der Hautalterung: Hautfeuchtigkeit, Hautelastizität und Hautrauigkeit. Aktuelle Dermatol. 2015, 41, 529–534.
[CrossRef]
Choi, F.D.; Sung, C.T.; Juhasz, M.L.; Mesinkovsk, N.A. Oral Collagen Supplementation: A Systematic Review
of Dermatological Applications. J. Drugs. Dermatol. 2019, 18, 9–16.
Banerjee, P.; Shanthi, C. Cryptic Peptides from Collagen: A Critical Review. Protein Pept. Lett. 2016, 23,
664–672. [CrossRef]
Kim, D.U.; Chung, H.C.; Choi, J.; Sakai, Y.; Lee, B.Y. Oral Intake of Low-Molecular-Weight Collagen
Peptide Improves Hydration, Elasticity, and Wrinkling in Human Skin: A Randomized, Double-Blind,
Placebo-Controlled Study. Nutrients 2018, 10. [CrossRef] [PubMed]
Wong, R.; Geyer, S.; Weninger, W.; Guimberteau, J.C.; Wong, J.K. The Dynamic Anatomy and Patterning of
Skin. Exp. Dermatol. 2016, 25, 92–98. [CrossRef] [PubMed]
Krutmann, J.; Bouloc, A.; Sore, G.; Bernard, B.A.; Passeron, T. The Skin Aging Exposome. J. Dermatol. Sci.
2017, 85, 152–161. [CrossRef] [PubMed]
Herbig, L.E.; Kohler, L.; Eule, J.C. High Resolution Imaging of the Equine Cornea Using the
DUB((R))-SkinScanner v3.9. Tierarztl Prax Ausg G Grosstiere Nutztiere 2016, 44, 360–367. [CrossRef] [PubMed]
Nutrients 2019, 11, 2494
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
32.
33.
13 of 14
International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use.
ICH Harmonised Guideline: Integrated addendum to ICH E6(R1): Guideline for Good Clinical Practice E6(R2);
European Medicines Agency: London, UK, 2016.
EU Guidelines to Good Manufacturing Practice; European Commission Guidelines Volume 4, Commission
Directives 91/356/EEC; European Commission: Brussels, Belgium, 2010.
Heinrich, U.; Koop, U.; Leneveu-Duchemin, M.C.; Osterrieder, K.; Bielfeldt, S.; Chkarnat, C.; Degwert, J.;
Hantschel, D.; Jaspers, S.; Nissen, H.P.; et al. Multicentre Comparison of Skin Hydration in terms of Physical-,
Physiological- and Product-Dependent Parameters by the Capacitive Method (Corneometer CM 825). Int. J.
Cosmet. Sci. 2003, 25, 45–53. [CrossRef]
Stroumza, N.; Bosc, R.; Hersant, B.; Hermeziu, O.; Meningaud, J.P. [Benefits of Using the Cutometer to
Evaluate the Effectiveness of Skin Treatments in Plastic and Maxillofacial Surgery]. Rev. Stomatol. Chir.
Maxillofac. Chir. Orale 2015, 116, 77–81. [CrossRef]
Friedman, P.M.; Skover, G.R.; Payonk, G.; Kauvar, A.N.; Geronemus, R.G. 3D In-Vivo Optical Skin Imaging
for Topographical Quantitative Assessment of Non-Ablative Laser Technology. Dermatol. Surg. 2002, 28,
199–204. [CrossRef]
International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals
for Human Use. ICH Harmonised Tripartite Guideline: Statistical Principles for Clinical Trials E9; European
Medicines Agency: London, UK, 1998.
Student. The Probable Error of a Mean. Biometrika 1908, 6, 1–25. [CrossRef]
Costigan, T. Bonferroni Inequalities and Intervals. In Encyclopedia of Biostatistics, 2nd ed.; Armitage, P.,
Colton, T., Eds.; John Wiley & Sons: New York, NY, USA, 2005; Volume 8, pp. 421–425.
Schulz, K.F.; Altman, D.G.; Moher, D.; Group, C. CONSORT 2010 Statement: Updated Guidelines for
Reporting Parallel Group Randomised Trials. BMC Medicine 2010, 8, 18. [CrossRef]
Buckley, M. Species Identification of Bovine, Ovine and Porcine Type 1 Collagen; Comparing Peptide Mass
Fingerprinting and LC-Based Proteomics Methods. Int. J. Mol. Sci. 2016, 17, 445. [CrossRef]
Asserin, J.; Lati, E.; Shioya, T.; Prawitt, J. The Effect of Oral Collagen Peptide Supplementation on Skin Moisture
and the Dermal Collagen Network: Evidence from An Ex Vivo Model and Randomized, Placebo-Controlled
Clinical Trials. J. Cosmet. Dermatol. 2015, 14, 291–301. [CrossRef] [PubMed]
Inoue, N.; Sugihara, F.; Wang, X. Ingestion of Bioactive Collagen Hydrolysates Enhance Facial Skin Moisture
and Elasticity and Reduce Facial Ageing Signs in A Randomised Double-Blind Placebo-Controlled Clinical
Study. J. Sci. Food Agric. 2016, 96, 4077–4081. [CrossRef] [PubMed]
Proksch, E.; Schunck, M.; Zague, V.; Segger, D.; Degwert, J.; Oesser, S. Oral Intake of Specific Bioactive
Collagen Peptides Reduces Skin Wrinkles and Increases Dermal Matrix Synthesis. Skin Pharmacol. Physiol.
2014, 27, 113–119. [CrossRef] [PubMed]
Proksch, E.; Segger, D.; Degwert, J.; Schunck, M.; Zague, V.; Oesser, S. Oral Supplementation of Specific
Collagen Peptides has Beneficial Effects on Human Skin Physiology: A Double-Blind, Placebo-Controlled
Study. Skin Pharmacol. Physiol. 2014, 27, 47–55. [CrossRef]
Schunck, M.; Zague, V.; Oesser, S.; Proksch, E. Dietary Supplementation with Specific Collagen Peptides Has
a Body Mass Index-Dependent Beneficial Effect on Cellulite Morphology. J. Med. Food 2015, 18, 1340–1348.
[CrossRef]
Hong, H.; Fan, H.; Chalamaiah, M.; Wu, J. Preparation of Low-Molecular-Weight, Collagen Hydrolysates
(Peptides): Current Progress, Challenges, and Future Perspectives. Food Chem. 2019, 301, 125222. [CrossRef]
Iwai, K.; Hasegawa, T.; Taguchi, Y.; Morimatsu, F.; Sato, K.; Nakamura, Y.; Higashi, A.; Kido, Y.; Nakabo, Y.;
Ohtsuki, K. Identification of Food-Derived Collagen Peptides in Human Blood after Oral Ingestion of Gelatin
Hydrolysates. J. Agric. Food Chem. 2005, 53, 6531–6536. [CrossRef]
Ichikawa, S.; Morifuji, M.; Ohara, H.; Matsumoto, H.; Takeuchi, Y.; Sato, K. Hydroxyproline-Containing
Dipeptides and Tripeptides Quantified at High Concentration in Human Blood after Oral Administration of
Gelatin Hydrolysate. Int. J. Food Sci. Nutr. 2010, 61, 52–60. [CrossRef]
Yazaki, M.; Ito, Y.; Yamada, M.; Goulas, S.; Teramoto, S.; Nakaya, M.A.; Ohno, S.; Yamaguchi, K. Oral
Ingestion of Collagen Hydrolysate Leads to the Transportation of Highly Concentrated Gly-Pro-Hyp and
Its Hydrolyzed Form of Pro-Hyp into the Bloodstream and Skin. J. Agric. Food Chem. 2017, 65, 2315–2322.
[CrossRef]
Nutrients 2019, 11, 2494
34.
35.
36.
37.
38.
14 of 14
Osawa, Y.; Mizushige, T.; Jinno, S.; Sugihara, F.; Inoue, N.; Tanaka, H.; Kabuyama, Y. Absorption and
Metabolism of Orally Administered Collagen Hydrolysates Evaluated by the Vascularly Perfused Rat
Intestine and Liver in Situ. Biomed. Res. 2018, 39, 1–11. [CrossRef]
Taga, Y.; Kusubata, M.; Ogawa-Goto, K.; Hattori, S. Identification of Collagen-Derived Hydroxyproline
(Hyp)-Containing Cyclic Dipeptides with High Oral Bioavailability: Efficient Formation of Cyclo(X-Hyp)
from X-Hyp-Gly-Type Tripeptides by Heating. J. Agric. Food Chem. 2017, 65, 9514–9521. [CrossRef] [PubMed]
Shigemura, Y.; Iwasaki, Y.; Tateno, M.; Suzuki, A.; Kurokawa, M.; Sato, Y.; Sato, K. A Pilot Study for
the Detection of Cyclic Prolyl-Hydroxyproline (Pro-Hyp) in Human Blood after Ingestion of Collagen
Hydrolysate. Nutrients 2018, 10, 356. [CrossRef] [PubMed]
Zague, V. A New View Concerning the Effects of Collagen Hydrolysate Intake on Skin Properties. Archives of
dermatological research 2008, 300, 479–483. [CrossRef] [PubMed]
Zague, V.; do Amaral, J.B.; Rezende Teixeira, P.; de Oliveira Niero, E.L.; Lauand, C.; Machado-Santelli, G.M.
Collagen Peptides Modulate the Metabolism of Extracellular Matrix by Human Dermal Fibroblasts Derived
from Sun-Protected and Sun-Exposed Body Sites. Cell Biol. Int. 2018, 42, 95–104. [CrossRef]
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