Comparison of Vitamin D Levels in Patients
with and without Acne: A Case-Control Study
Combined with a Randomized Controlled
, Jeong-Min Ha
, Young-Ho Lee
, Young Lee
, Young-Joon Seo
, Jeung-Hoon Lee
, Myung Im
1Department of Dermatology, School of Medicine, Chungnam National University, Daejeon, Korea,
2Department of Anatomy, School of Medicine, Chungnam National University, Daejeon, Korea
Vitamin D plays an important role in the immune system, and its deficiency has been impli-
cated in various skin diseases, including atopic dermatitis and psoriasis. Acne is a common
inflammatory skin disease; however, the association with vitamin D remains unclear.
We evaluated vitamin D levels in patients with acne to determine the effect of vitamin D
This study included 80 patients with acne and 80 healthy controls. Serum 25-hydroxyvita-
min D (25(OH)D) levels were measured, and demographic data were collected. Vitamin D-
deficient patients were treated with oral cholecalciferol at 1000 IU/day for 2 months.
Deficiency in 25(OH)D was detected in 48.8% of patients with acne, but in only 22.5% of the
healthy controls. The level of 25(OH)D was inversely associated with the severity of acne,
and there was a significant negative correlation with inflammatory lesions. In a subsequent
trial, improvement in inflammatory lesions was noted after supplementation with vitamin D
in 39 acne patients with 25(OH)D deficiency.
Limitations of the study include the small number of patients in the supplementation study
and the natural fluctuation of acne.
PLOS ONE | DOI:10.1371/journal.pone.0161162 August 25, 2016 1/11
Citation: Lim S-K, Ha J-M, Lee Y-H, Lee Y, Seo Y-J,
Kim C-D, et al. (2016) Comparison of Vitamin D
Levels in Patients with and without Acne: A Case-
Control Study Combined with a Randomized
Controlled Trial. PLoS ONE 11(8): e0161162.
Editor: Yiqun G. Shellman, University of Colorado
Denver School of Medicine, UNITED STATES
Received: November 5, 2015
Accepted: July 30, 2016
Published: August 25, 2016
Copyright: © 2016 Lim et al. This is an open access
article distributed under the terms of the Creative
Commons Attribution License, which permits
unrestricted use, distribution, and reproduction in any
medium, provided the original author and source are
Data Availability Statement: Data are available from
the Chungnam National University Hospital (E-mail:
email@example.com, Phone: 82-42-280-6715).
Funding: The author(s) received no specific funding
for this work. This study was supported by a grantof
the Korea Healthcare technology R&D Project,
Ministry of Health & Welfare, Republic of Korea
(Grant No.: HI14C1379).
Competing Interests: The authors have declared
that no competing interests exist.
Vitamin D deficiency was more frequent in patients with acne, and serum 25(OH)D levels
were inversely correlated with acne severity, especially in patients with inflammatory
Acne is a common and complex skin disorder that distresses many patients because of its
chronicity. Although multiple factors contribute to acne development, chronic inflammation is
an important mechanism. Several inflammatory mediators such as cytokines, defensins, and
neuropeptides have been identified in acne lesions. In addition, Propionibacterium acnes (P.
acnes) triggers cytokine activation by Toll-like receptors, which means that the innate immune
system is also important for acne development.
Vitamin D has a number of functions in addition to its well-known role as a modulator of cal-
cium metabolism and homeostasis. It affects both the innate and adaptive immune system
through its effects on T and B lymphocytes, dendritic cells, and macrophages,[3,4] and it is asso-
ciated with systemic inflammatory diseases such as rheumatoid arthritis, systemic lupus erythe-
matosus, and inflammatory bowel disease.[5,6] In dermatological diseases, it plays an important
role as an immune modulator in atopic dermatitis, psoriasis, vitiligo, and alopecia.[7–10]
A few in vitro studies have published data that support the theory that vitamin D has a func-
tional role in acne development. Identifying vitamin D receptors in human sebocytes and mod-
ulation of lipid and cytokine production by vitamin D suggest the possible association between
vitamin D and acne pathophysiology.[11–13] However, evidence is lacking regarding the clini-
cally relevant action of vitamin D in the development of acne, and its potential efficacy as a
therapeutic agent in acne also requires clarification. Accordingly, we evaluated vitamin D levels
in serum of acne patients compared to healthy controls, and the effects of vitamin D supple-
mentation. To the best of our knowledge, this is the first study to have investigated the role of
vitamin D in the pathogenesis and treatment of acne in a clinical setting.
Materials and Methods
This case-control study included 80 patients with acne and 80 age- and sex-matched healthy
controls. All of the patients and controls were enrolled in this study from November 2014 to
February 2015 to avoid seasonal variation in vitamin D levels (recruitment end date, 28 Febru-
ary 2015; overall trial end date, 30 April 2015). Demographic data such as age, sex, body mass
index (BMI), smoking history, and sunscreen use were collected prior to enrollment. Exclusion
criteria prohibited enrollment of patients and controls who were receiving therapeutic inter-
ventions such as acne treatment, systemic corticosteroids, vitamin D supplements, or subjects
with concomitant inflammatory diseases. This study was approved by the Institutional Review
Board of Chungnam National University Hospital (CNUH 2014-07-013; date of approval, 24
July 2014). All of the subjects provided written informed consent before participating in the
study. We did not include children in this study; written consent was obtained from the sub-
jects themselves. This study was also approved by the ISRCTN registry (ISRCTN11007935;
date of approval, 15 October 2015). Because we were initially unaware of the ISRCTN registry,
the registration data were obtained after the study end date. The authors confirm that all ongo-
ing and related trials for this drug/intervention are registered.
Vitamin D and Acne
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Serum vitamin D analysis
Patients and controls had their serum 25-hydroxyvitamin D3 (25(OH)D) concentrations
measured. Blood samples were collected from veins and analyzed within 24 h of sampling
using the Roche Cobas e411 (Roche Diagnostics System, Switzerland). Levels of 25(OH)D
were categorized as adequate (>20 ng/mL), inadequate (12–20 ng/mL), or deficient (<12 ng/
mL) according to the guidelines set by the Food and Nutrition Board of the Institute of Medi-
Vitamin D supplementation
A subsequent blinded controlled study was performed in acne patients with 25(OH)D defi-
ciency. Each of the 39 patients were provided with a unique patient number and randomly
assigned to one of two groups by computer: one group underwent 2-month oral administration
of cholecalciferol (one drop of 1000 IU/day), and the other group received an identical-appear-
ing placebo drop. Any other topical or systemic acne treatments, except for standard washing
and moisturizing, were not allowed. The patients were assessed at the beginning of treatment
and at 2, 4, and 8 weeks during treatment.(Fig 1)
Fig 1. Flow diagram of randomized trial (CONSORT 2010 Flow Diagram).
Vitamin D and Acne
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Clinical assessments were performed by three blinded independent dermatologists, and their
objective assessments and inter-rater reliability were evaluated. Digital photographs at baseline
and at each follow-up visit were used for the clinical assessments. Counts of non-inflammatory
lesions (comedones) and inflammatory lesions (papules, pustules, and nodules) were also
made at each visit.
The severity of acne was assessed according to the global acne grading system (GAGS)
score. GAGS divides the face, chest, and back into six areas (forehead, each cheek, nose,
chin, chest, and back) and assigns a factor to each area on the basis of the surface area and dis-
tribution/density of pilosebaceous units. Each type of lesion is given a value depending on
severity: no lesions = 0; comedones = 1; papules = 2; pustules = 3; and nodules = 4. The score
for each area (local score) is calculated using the formula: Factor × Grade (0–4). The global
score is the sum of the local scores, and acne severity is graded using the global score. A score
of 1–18 is considered mild; 19–30, moderate; 31–38, severe; and >39, very severe.
Statistical analyses were performed using SPSS version 15 (SSPS Inc., Chicago, IL). The chi-
square test was performed to compare the categorical data (Tables 1and 2). The correlation
between the serum vitamin D level and inflammatory acne lesions was evaluated using Pear-
son’s correlation analysis. Changes in the vitamin D levels after vitamin D supplementation
were evaluated with the Wilcoxon signed-rank test. The vitamin D levels according to disease
severity and the median percentile changes from baseline in acne lesions after vitamin D sup-
plementation were analyzed by the Kruskal–Wallis test followed by the Mann–Whitney U test
for post hoc comparison. Pvalues of <0.05 were considered statistically significant.
The age, sex, BMI, smoking history, and use of sunscreen were the same when comparing the
two groups (Table 1). There were no significant differences in the mean 25(OH)D concentra-
tion between the groups, although it was lower in patients compared to the controls. However,
the prevalence of 25(OH)D deficiency was significantly higher in patients with acne compared
to healthy controls (48.8% vs. 22.5%; P= 0.019) (Table 1,Fig 2). The threshold of 25(OH)D
deficiency in this study was defined as <12 ng/mL, according to the guidelines set by the Food
and Nutrition Board of the Institute of Medicine. The distribution pattern of the 25(OH)D
levels in the two groups showed the widest gap in the 12-ng/mL area (S1 Fig).
Table 1. Baseline demographic and clinical characteristics of patients with acne and controls.
Acne (n = 80) Controls (n = 80) Pvalue
Age (years) 20.9 ±4.1 21.0 ±5.7 0.768
Sex (F/M), n (%) 47/33 (58.6/41.4) 41/39 (51.3/48.7) 0.482
)21.8 ±3.8 20.2 ±4.9 0.894
Smoking (yes), n (%) 16 (20.0) 11 (13.8) 0.645
Using sunscreen, n (%) 47 (58.8) 58 (72.5) 0.356
Serum 25(OH)D (ng/mL) 13.1 ±9.8 15.2 ±7.2 0.112
Vitamin D deﬁciency, n (%) 39 (48.8) 18 (22.5) 0.019*
All values are presented as mean ±SD unless otherwise stated. BMI, body mass index; 25(OH)D, 25-hydroxyvitamin D.
Vitamin D and Acne
PLOS ONE | DOI:10.1371/journal.pone.0161162 August 25, 2016 4/11
We determined whether vitamin D deficiency was influenced by any factor. No significant
correlation was seen between deficient 25(OD)D levels and age, sex, disease duration, BMI,
family history, smoking, sunscreen use, and trunk involvement. The only factor affecting 25
(OH)D deficiency was disease severity. In total, 15 of the 18 patients (83.3%) in the severe
group were 25(OH)D-deficient, whereas only 6 of the 27 (22.2%) patients in the mild group
were deficient (Table 2). In addition, the mean 25(OH)D concentration was inversely associ-
ated with the severity of acne (Fig 3). There was not a significant correlation between 25(OH)D
levels and the number of non-inflammatory lesions. However, the number of inflammatory
lesions was significantly and negatively correlated with vitamin D concentrations (r = −0.512;
P<0.001) (Fig 4), signifying a possible link between the extent of vitamin D deficiency and the
degree of acne inflammation.
We also assessed the therapeutic efficacy of vitamin D supplementation in acne patients
with 25(OD)D deficiency. The 39 patients showing vitamin D deficiency were randomly
assigned to the vitamin D (n = 20) or placebo (n = 19) group. The two groups did not
Table 2. Results of vitamin D deficiency according to influencing factors.
Total Mean 25(OH)D Vitamin D Deﬁciency Pvalue
no. (ng/mL) n (%)
<20 36 13.19 ±2.8 20 (55.6)
20 44 11.01 ±1.8 19 (43.2) 0.624
M 33 11.22 ±3.8 17 (53.1)
F 47 12.98 ±3.2 22 (46.9) 0.892
<3 41 10.89 ±1.8 24 (58.5)
3 39 13.31 ±2.2 15 (38.5) 0.211
Normal or less (<23) 50 10.89 ±1.4 28 (56.0)
Overweight or obese (23) 30 13.31 ±1.2 11 (36.7) 0.189
No 58 9.99 ±1.4 30 (51.7)
Yes 22 14.21 ±0.5 9 (40.9) 0.503
No 64 10.44 ±0.8 29 (45.3)
Yes 16 13.76 ±1.8 10 (62.5) 0.412
No 33 13.51 ±1.2 14 (42.4)
Yes 47 10.69 ±0.6 25 (53.2) 0.398
No 54 15.56 ±1.3 22 (40.7)
Yes 26 8.69 ±0.7 17 (65.3) 0.098
Mild 27 17.37 ±0.6 6 (22.2)
Moderate 35 11.89 ±1.0 18 (51.4)
Severe 18 7.04 ±0.5 15 (83.3) 0.002**
25(OH)D values are presented as mean ±SD. Pvalues are for comparison of vitamin D deﬁciency. BMI, body mass index; 25(OH)D, 25-hydroxyvitamin D.
Vitamin D and Acne
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significantly differ by any demographic or clinical factor. Vitamin D supplementation for 2
months resulted in a statistically significant increase in 25(OH)D levels (P<0.001) (Fig 5A)
and produced a clinical improvement compared to placebo (Fig 5B). There were no differences
in the non-inflammatory and total lesion counts between the groups. However, the inflamma-
tory lesions showed a statistically significant improvement in the vitamin D group compared
with the control group (P<0.05). Inflammatory lesions in the vitamin D group decreased by
34.6% after 8 weeks of treatment, whereas those in the control group decreased by 5.8% (Fig
5C). None of the patients reported discontinuation of the intervention, and there were no
To the best of our knowledge, this is the first study to assess vitamin D status in acne patients.
There were no significant differences in the mean vitamin D concentration between acne
Fig 2. Percentages of patients with different vitamin D levels.
Fig 3. Vitamin D levels and disease severity (*P<0.05, ***P<0.001).
Vitamin D and Acne
PLOS ONE | DOI:10.1371/journal.pone.0161162 August 25, 2016 6/11
patients and healthy controls. This may be the result of the characteristics of vitamin D status
in the Korean population. As shown in Fig 1, most healthy control subjects had inadequate lev-
els of vitamin D, as reported previously in the general Korean population.[16–18] However,
the prevalence of 25(OH)D deficiency was significantly higher in patients with acne (48.8%)
compared to healthy controls (22.5%). A similar finding was reported in a previous clinical
trial in which patients with nodulocystic acne showed relatively low serum vitamin D levels.
To understand the vitamin D status associated with acne patients, we investigated the fac-
tors that influence vitamin D deficiency. Although obesity and decreased sun exposure using
sunscreen are known to be associated with low 25(OH)D levels,[20–24] they were not associ-
ated with vitamin D deficiency in this study. The serum vitamin D level is also influenced by
food such as fish oil or pork[16,17]; unfortunately, however, we were unable to evaluate the die-
tary habits of the patients. Our analysis revealed that the only factor associated with 25(OH)D
deficiency was acne severity, similar to previous findings that disease severity of atopic derma-
titis, psoriasis, and vitiligo is associated with lower levels of vitamin D.[7–9] Patients with
severe acne may be subject to more psychological stress, and may tend to avoid spending
extended periods outdoors, suggesting a possible explanation for low vitamin D levels in
patients with severe acne.
Fig 4. Correlation between vitamin D levels and inflammatory acne.
Vitamin D and Acne
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In the randomized controlled trial of 39 acne patients with vitamin D deficiency, oral vita-
min D supplementation produced a significant improvement in acne inflammation. In con-
trast, a previous study found no effect of vitamin D supplementation on acne lesions.
However, this result was due to the fact that patients with acne had polycystic ovary syndrome,
and there was no consideration of the specific acne type, such as inflammatory lesions. The
observed anti-inflammatory effects of vitamin D have several biological mechanisms. The
expression of inflammatory biomarkers, such as interleukin (IL)-6, IL-8, and matrix metallo-
proteinase 9, is reduced by treatment with vitamin D in cultured sebocytes. There is also
published evidence that vitamin D inhibits P.acnes-induced Th17 differentiation with reduced
expression of IL-17, an inflammatory cytokine that is increased in acne patients. In addi-
tion, vitamin D has antimicrobial effects by inducing antimicrobial peptides such as LL-37 in
human sebocytes. These previous reports support the theory that vitamin D has an
immune regulatory function in sebocytes, which supports the possible anti-inflammatory
effects of vitamin D in acne patients.
Our vitamin D supplementation trial had a few potential limitations, such as the use of a
low dose and short duration of treatment. The daily dose of vitamin D in this study was 1000
Fig 5. Clinical effects of vitamin D supplementation in patients with acne. (A) Change in vitamin D levels after vitamin D supplementation
(***P<0.001). (B) Photographs showing clinical improvement in a patient with acne. Photographs showing baseline (left) and last visit (right).
(C) Median percentile changes from baseline in acne lesions (*P<0.05).
Vitamin D and Acne
PLOS ONE | DOI:10.1371/journal.pone.0161162 August 25, 2016 8/11
IU/day, lower than in previous studies.[27,28] However, some studies have shown that a daily
dose of 1000 IU vitamin D is an effective treatment for atopic dermatitis.[29,30] In addition, as
shown in Fig 4, the vitamin D level was significantly improved by 1000 IU/day for 2 months,
although it was an inadequate level. Future trials need to examine the impact of regimens that
are more likely to achieve adequate levels of vitamin D, which is often associated with optimal
health. Moreover, given the frequent disease fluctuations that characterize acne, future trials of
more patients with a longer treatment duration are needed to determine if acne lesions recur
after the initial improvement or if the benefits are sustained by longer duration of treatment.
In conclusion, we found that vitamin D deficiency was more frequent in patients with acne,
which was inversely correlated with disease severity, indicating a potential role of vitamin D
deficiency in acne pathogenesis. A further study with a larger sample size is needed to confirm
our results because of the small number of patients in the supplementation study and the natu-
ral fluctuation of acne. Evaluation of the tissue level of vitamin D in patients with acne will also
require a further study to reveal direct evidence of the effect of vitamin D on acne.
S1 Fig. Distribution pattern of 25(OH)D levels in patients and controls. The horizontal axis
represents the 25(OH)D levels (ng/mL), and the vertical axis represents the cumulative fre-
quency of 25(OH)D levels (%).
S1 File. CONSORT 2010 Checklist.
S2 File. Study information and protocol.
S3 File. Study information and protocol (Original language).
This study was supported by a grant of the Korea Healthcare technology R&D Project, Ministry
of Health & Welfare, Republic of Korea (Grant No.: HI14C1379).
A preliminary version of the results was presented in the 67
annual meeting of Korean der-
Conceptualization: MI YL YJS CDK JHL.
Data curation: MI SKL.
Formal analysis: MI YHL.
Funding acquisition: MI CDK JHL.
Methodology: MI SKL.
Project administration: MI.
Vitamin D and Acne
PLOS ONE | DOI:10.1371/journal.pone.0161162 August 25, 2016 9/11
Software: MI YHL.
Supervision: MI JHL.
Validation: MI YHL.
Writing –original draft: SKL JMH.
Writing –review & editing: MI.
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