J. Soc.Cosmet.Chem., 26, 227-234 (May 1975)
ClinicalEvaluationof BabyOil as a Dermal
Moisturizer
EUGENE R. JOLLY, M.D., Ph.D. andCHARLES A. SLOUGHFY*
Synopsis-Apopulationof 106 adult femaleswho exhibitedtoughened,cracked,and inflamedskinsof the elbows,knees,shins,and heelswere selectedfor the evaluation of the SKIN MOISTURIZING
ACTIONS of BABY OIL. The baby oil was applied at
leasttwicedailyduringa 4-weekstudyperiodto the specified siteson onesideof the body.The contralateral sitesservedas untreatedcontrols.Ratingof the skin sitesat the outsetof the study,duringa 2-weekinterimexamination, andat the endof 4 weeksdefineda markedand progressive improvement of sitestreatedwith the baby oil. Conversely, untreatedsitestendedto worsenduringthe studyperiod.
A statisticalanalysisof the data revealedthat the moisturizingactionswere l•ghly significant at boththe 2- and 4-weekexamination times.All ratingswere madewithout foreknowledge of which sideof the body had been treated.Photographs obtainedin 10 subiects clearlyillustratedthe differences betweenskinof treatedversusnontreated sites. Followingdiscontinuation of the babyoil application, skinsof the treatedsitestendedto become drier within the first 48 hours. These data suggestthat the skin moisturizing actionsof the baby oiI are not protracted. INTRODUCTION
According to Blank(1), primarytherapyfor prophylaxis or correction of dry,scaly,eroded,andenflamed skinshouldbe directedtowardmaintenance of optimumhydrationof stratumcornea.Studieshave shown(2, 3) that naturalskinlipidsare not very effectivein preventingwaterlossundercond't'_'ons of low environmental humidity.Nor canpassage of waterthroughthe stratumlucidurnand stratumgranulosum, the preservers of body water and electrolytes, compensate for enhancedevaporation.
Jellinek(4) pointsout that removalof surfacelipids throughfrequent useof detergents or exposure to organicsolvents alsofacilitatesskindrying. He stresses that moisturein the stratumcorncureis bound by hydrophilic
components includingaminoacids,penroses, andphospholipids. If the skinis *BiometricTesting, Inc., EnglewoodCliffs, N.J.
227
29.8
JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS
strippedof lipids,then thesehydrophiliemodulesare readilywashedout. In addition,when the fat layer is removed,the surfaceof the stratumcomeurn becomes toughened, exposing greaterareasof skin,andspeedingthe evaporation process.
Powersand Fox (5) reportthat emollientproducts,formulatedto maintain skinintegrityunderconditions of excessive waterloss,vary markedlyin effectiveness.Utilizing silicagel dessicators, theseinvestigators studieda seriesof materialsfor effectiveness in retardingskin dehydration.Many of the formulations,labeledasskinsofteners,actuallyincreasedwater loss,oneasmuchas 56%. PetrolatumUnited StatesPharmacopoeia(USP) was the mosteffective barriermaterialtestedfor maintenanceof derrealhydration.
Anhydrous lanolin,mineraloil, and coldereamalsoprovedto be effective barriers.Spruitt (6) alsoquantitatedwater lossfrom the skin followingapplicationof a variety of materials.Flow of water was decreasedfrom 500- to 1000-foldby aliphaticproducts(mineral-oilbased). Unsaturatedvegetable oilsprovidedonly slightprotection,whereassaturatedfats were intermediate in activity. Emulsionstended to increaseevaporation.Eisner's(7) results supportthoseof Fox and Powersand of Spruitt.Ointmentsor lotionscontaining hmnectantsand surfaetants againprovedineffectivebarriers;in this ease, with regardto the penetrationof an experimentalfilm modelby a seriesof noxiousmaterialsincluding urine, feeal suspensions, acids, and bases.Con-
versely,babyoil andpetrolatumpreventedpassage of thenoxiants. Babyoil with a mineraloil baseremainsperhapsthe mostwidely employed skin emollientor softener.In spite of its hydrophobieproperties,assuming that the principlesof therapyexpressed by Blankand other investigators are valid, baby oil can alsobe properlytermeda skinmoisturizer.Publisheddata suggestthat baby oil as a liquid hydrocarbon,that is capableof providingan effectivebarrier againstwater loss,would provide superiormoisturizingactions,and that its utility in protectingthe vulnerableskinof infantswould be equally apparentafter applicationto adults who exhibit sequelaeto the variety of skin trauma induced by mechanicaland environmentalassaults. The presentstudy was designedto clinically define the moisturizingactionsof a commercially-available baby oil• when appliedto the toughened, cracked,and inflamedskinsof the elbows,knees,heels,and shinsof adults. EXPERIMENTAL
METHODS
The study was conductedusinga single-blinddesignwith the subjects servingastheir own controls.The studygroupwascomposed of 111females with an age rangeof 13 to 72 yearsand an averageage of approximately 31 years.Treatment sidesand contralateralcontrol areas (elbows, knees,heels,
*•Suppliedby Baby ProductsCompany,Johnson& Johnson,New Brunswick,N.J.
CLINCAL
EVALUATION
OF
BABY
OIL
229
and shins) were randomizedaccordingto a scheduledevelopedprior to initiationof the study.To be eligible for participation,candidateswere requiredto be free of any dermatologicaI pathologyrelatedto systemicdiseases and to exhibitseverityof symptomsconformingto a rating of 2 or higheron a 5-pointratingscalefor at least2 of the 4 specifiedskinsitesasfollows. A. Elbows and knees
0=smoothvisuallyand to the touch 1="snow"visiblein creases; slightlyroughto the touch 2--scalesand "snow"visible;moderatelyroughto the touch 3=pronouncedscalingandroughness to the touch 4=crackingassociated with severeroughness to the touch B. Heels
0=smoothvisuallyand to the touch l=rough to the touchwith "snow"and crackingjust visible 2=roughto the touch;crackingand scalingevident 3=quite roughto the touch;scalingand crackingpronounced 4=very roughto the touch;extremescalingandcracking C. Tibia
0=smoothvisuallyand to the touch i--smooth to the touch; "snow"visible in creases
2=scalingand slightglazing 3=pronouncedscalingand slightlyroughto the touch 4=severescalingand cracking;very roughto the touch
Followingthe baselineexamination,subjectswere instructedto utilize at least2 dropsof the baby oil on the designatedareasat leasttwice daily (on arisingand at bedtime) duringa 4-weekstudyperiod.While the oil was to be appliedsparinglyso that it was not recognizableat the timesof clinical assessment, they were requestedto useenoughto coverthe test sitescompletely.Useof otherskinconditioning preparations duringthe studywasprohibited.The subiectswere againrated after 2 and 4 weeks.All examinations were conducted in a uniform manner with elbows and knees bent at a 90 ø
angle.Discussions betweenthe investigatorand subjectwere prohibited,and at no time was the investigatormade aware of the identity of the treatment side.
Finally, photographicdocumentation of effectiveness was obtainedfrom 20
of the subjects. Theseindividuals hadbeenselected at randomandspecified by subiectnumberprior to therapeutictrial. Each of the 4 siteson both the
rightandleft sidesof the subiects werephotographed at the scheduled examinationsand again either 24 or 48 hoursfollowingtreatmentwithdrawal to allow a determinationof durationof baby oil activity.
230
JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS RESULTS
Valid data were obtainedfrom 106 of the initial 111 participants.Four subjeetswere excludedfrom the final statisticalanalysisbecauseof insuttleient baselinedermatologieinvolvementand one becauseof insuttleientrating data due to a missedrating session causedby intercurrentillness. That the initial severityof the dermatologieal signswere comparablefor the treatmentsitesandcontralateral untreatedsitesamongthe populationcan be ascertained by reviewof Table I. In general,skin of elbows,knees,and
heelsexhibiteda greaterdegreeof drying,sealing,androughness at the outsetof the trialsin comparison to shins. Skinmoisturizing activitiesof the babyoil areillustratedin Fig. 1. Severity of the signswasdecreased in comparison to baselinereadingsto a significant extent at all 4 treatmentsites.Conversely,untreated sitestended to become
more severelyafflictedover the 4-weekstudyperiod.Actually,tibial areas weresignificantly worseat the 4-weekevaluation(P=0.01).Improvement appeared to be progressive with continuedtreatment.However, even after 2 weeks,the degrees of benefitwereclearlydemonstrable. A summary of the statistical analyses of the datais presentedon Table II. Results of evaluations of the 10 individuals who returned to the clinic 24
hoursafterthe babyoil applications were terminatedand the additional10 who reportedto the clinic48 hourslater are summarizedin Table III.
Thedatasuggest thattheprotectant moisturizing actions of babyoil donot persist for extended periodsfollowingtermination of therapy,asskinof treated sitestendedto returnto thepretreatment stateduringthe 24- and48-hour follow-upperiods.
Meanscores calculated fromraw dataandobtainedutilizingthe described objective methods provethethesis thatthecompletely nonpolar liquidhydroTable I
Distribution of Sitesby TreatmentGroupandInitial Severityof Dermatologic Signs Site _
Elbow
Knee
Heel
Tibial Area
Sever'tya Treated Untreated Treated Untreated Treated Untreated Treated Untreated 0 1 2 3 4
TOTALS:
5 24 53 • 20
3 27 52 • 20
7 40 48 • 10
4
4
1
106
106
106
a Median severity. •'S-e protocol for definitions.
9 ,35 50 • .11
4 20 62 • 18
4 20 59 b 21
6 48 b 43 9
7 49 b 41 9
1
2
2
0
0
106
106
106
106
106
CLINICAL
EVALUATION
Mean
OF
BABY
OIL
231
Mean
Symptom Severity
Symptom
2-- •.......•.o•o
,Control
•%•"'• • ß,Control Severity
Score
Score
% •.....,...'--¸
.Baby Oil
1 i
--
0
1
2
3
4
'"'""--0 ,BabyOil
0
1
2
Weeks
3
4
Weeks
(a)
(b)
Mean Mean
Symptom Severity
Symptom Severity
.Control
Score
,Control
Score
.Baby Oil
1 --
0
1
2
3
,Baby Oil
1 m
4
0
1
Weeks
2
3
4
Weeks
(c)
(d)
Figure1. Reduction in meansymptom scores followingapplication of babyoil to various anatomicalsites:(a) heels;(b) elbows;(c) shins;(d) knees Table II
Mean DermatologicSeverity (ScoresBy Weeks) Week 2
Week 4
Baseline Score Mean Statistical Significance"Mean Statistical Significance" Elbows treated
1.9 2.0
1.1 2.0
0.001 0.311
1.0 2.1
0.001 0.066
1.6 1.6
1.0 1.7
0.001 0.543
0.9 1.7
0.001 0.245
treated
1.9
1.4
0.001
1.2
0.001
untreated
2.0
1.9
0.538
1.9
0.588
1.5 1.5
1.2 1.6
0.001 0.213
1.1 1.7
0.001 0.001
untreated Knees
treated untreated Heels
Tibial Areas
treated untreated
Statistical significance of changefrombaseline-Wilcoxon Matched-PairSignedRanks.
232
JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS Table III
Mean Severity Ratings 24 and 48 Hours After Treatment as Compared to the Ratings for the Last Treatment Day •
Mean Severityof Treated Sites Last day 24 Last day 48
Mean Severityof UntreatedSites Last day 24 Last day 48
of
hours
of
hours
of
hours
treatraent
after
treatment
after
treatment
after
of
hours
Elbows
1.4
2.1
0.9
1.8
2.6
2.6
2.3
Knees
0.7
1.8
0.7
0.9
2.6
2.5
1.2
1.4
Heels
1.2
1.8
1.3
1.9
2.7
2.8
2.2
2.4
Shins
1.0
1.9
0.9
1.6
2.4
2.4
1.7
1.7
treatm•ent after 2.2
Two separatetreatment groupscomposedof 10 subjectseach were evaluatedat 24 and 48 hours,respectively.
carbon,asrepresented by the babyoil, can exertclearlydemonstrable skin moisturizing action.This anomalywasevenmoreimpressively demonstrated photographically. Figures2 and 3 illustratecontrasts betweentreatedand untreated
sites.
Reviewof photographs fromall 20subjects alloweddefinition of similardegreesof benefit.Conversely, the follow-upphotographs taken at 24 and 48 hourslater exhibitedlessremarkabledifferences. The photographs, like the ratings,indicatethat deterioration is relativelyrapid when applications of the baby oil are stopped. DISCUSSION
An occ]usive film of a liquid hydrocarbon as affordedby the babyoff, accordingto availableevidence,providesa highlyeffectivemechanism for retardingwater lossevenunderextremes of low humidityin the environment. Sucha product,then,canappropriately be termeda skinmoisturizer despite its hydrophobic properties. In fact,occludingthe skinmay be a moreeffective mechanism for maintainingmoistureandprotectingthe stratumcorneum
thanattempts to promote penetration andskinretention of hydrophi]ic substances (e.g., aminoacidsand po]ypeptides) and/or o]eaceousmaterials.
The dataobtainedin thepresentstudyareclearlythe mostimpressive that we have obtainedin our clinic, althoughwe have had the opportunityto
evaluatemany "moisturizers," of which severalwere apparentlyeffective.
(ReceivedOctober10, 1974)
CLINICAL
(a)
EVALUATION
OF
BABY
OIL
233
(b)
Figure 2. Comparisonof (a) right and (b) left heelsprior to treatment
(a)
(b)
Figure 3. Comparisonof (a) right and (b) left heels following 4 weeks of ,baby oil treatment of left side
234
JOURNAL OF THE SOCIETY OF COSMETIC
CHEMISTS
REFERENCES
(1) I. H. Blank, Action of emollient creamsand their additives, Committee on Cosmet., 164, 412-5 (1957). (2) T. Winsor and G. G. Burch, Differential roles of layers of human epigastric skin on diffusionrate of water, Arch. Med., 74, 428-36 (1944). (3) S. Rothman,Principlesof percutaneousabsorption,J. Lab. Clin. Med., 28, 1305-21 (1943). (4) J. S. Jellinek, Emollients, Formulation and Function o)• Cosmetics,Wiley-Interscience, New York, 1970, pp. 351-3.
(5) C. Fox and D. H. Powers,The effectof cosmeticemulsions on the stratumcorneum, .[. Soc. Cosmet.Chem., 10, 109-16 (1959).
(6) D. Spruitt, Interferenceof somesubstances with water vapor losso{ human skin, Amer.Per.Cosmet.,37, 69-72 (1961). (7) H. Eisner,A methodfor the studyof the penetrabilityof liquid and semi-solid films usedin skinprotection,]. Invest. Derre., 10, 273-9 (1948).
