Infant Skincare: Olive versus Mineral Oil - Reviewing the Evidence

Community Practitioner, Feb 2011

Pauline Carpenter & Karen Richards

Abstract

In this paper, the Community Practitioner Journal’s Education Supplement ‘Infant Skincare’, and the associated research-based evidence that support the document are reviewed, in order to establish whether olive oil should be considered detrimental to the skin and that mineral oil should be deemed as the first choice for baby skin care regimes.  It was established that the application of solutions of oleic acid was the main focus of the evidence used to support the articles in the supplement and not olive oil, as is implied.  Also many of the statements made about olive oil and mineral oil were unsubstantiated and further investigation failed to support the claims asserted.  This review includes information about the chemical components of oils commonly utilised for massage and other skin care regimes, in order to indicate that olive oil cannot be dismissed and that mineral oil should still be used with caution until clear evidence-based research has been found.

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The Educational Supplement ‘Infant Skincare’, which accompanied the October 2010 Community Practitioner journal, prompted many parenting practitioners, who teach infant massage to parents, to question both the arguments posed in the supplement and their current practice vis-à-vis the supply of oils and the advice they give to parents.  The majority of infant massage teacher training providers and subsequently infant massage teachers, throughout the UK, encourage the use of vegetable oils for massage and suggest that mineral oil should be avoided.  The Infant Skincare articles[1]^, [2], on the contrary, suggest the opposite!  As these are supported by, what appears to be, a good deal of research-based evidence, confusion and uncertainty as to the advice to give parents now exists.

Olive oil – revisiting the evidence

Having reviewed the articles in the supplement and, in particular, the research-based evidence associated with the  effect certain oils1 (mainly olive oil and mineral oil) have on the skin, this review hopes to clarify the situation and alleviate any concerns parenting practitioners may have.  The articles in question1^, 2 are well referenced, but many statements within them are not.  For example, the assertion, in the educational supplement that: ‘evidence suggests that olive oil can be damaging to the skin barrier’ (page 511) was not referenced.  This review has undertaken an extensive search for some form of evidence to support the statement, rather than simply dismissing this claim.

The majority of research referred to1 and used as supporting evidence by the supplement, concerns the application of solutions of oleic acid, which is argued to be a major constituent of olive oil.  However, these studies[3]^{, [4], [5], [6]} do not give consideration to natural vegetable oils and are not concerned about the on-going health or repair of the skin.  Instead they concentrate on substances that are actually efficient at breaking down the skin barrier, in order to aid skin penetration to enhance drug absorption.

To date, only one study[7] has been found that compares the impact of topical oils on skin barrier function.  The study included olive oil and its effect when applied to damaged skin; although this was not the main focus of the enquiry.  The study7 directly investigated the effect of vegetable oils on the recovery of skin barrier function of mice after acute barrier disruption by tape-stripping had been carried out. The results showed that a single application of sunflower oil accelerates recovery of barrier function, mustard oil has the most deleterious effects on barrier function and olive oil delays the skin barrier recovery.  Therefore, suggesting that it is inadvisable to put olive oil on already damaged skin; not that it can damage the skin barrier.  It is necessary to point out that compromised/damaged skin is a contraindication to massage, regardless of the oil applied⁸.

It is indicated in the educational supplement that the percentage of oleic acid content in olive oil is ‘55% to 83%’ (page 51). Drawing on the results of the above mentioned study7, the sunflower oil evaluated had 29.6% oleic acid content, with 58.3% linoleic acid and an undetectable level of erucic acid.  (The usual range for a sunflower oil is - Linoleic Acid 48% -74 %; Oleic Acid 14% – 40%)9.  One of the mustard oils tested7 was found to have an undetectable level of oleic acid, with 34.1% of linoleic acid content and 41.5% erucic acid.  There was no reference made regarding levels of linoleic acid or erucic acid, in the olive oil used in the tests.

This begs the question, could it be the erucic acid content found in the mustard oil that is the damaging factor within the oil? Particularly as the level of oleic acid present in the mustard oil was undetectable, yet the mustard oil still proved to be damaging to the stratum corneum.  Furthermore, sunflower oil has the potential of having a comparatively high level of oleic acid9, whilst containing potentially high linoleic acid and low erucic acid7.   Evidence of the usual levels of linoleic and erucic acid within olive oil were not quoted in the supplement.  However, during the search for relevant information for this review, it was found that the usual percentage range of linoleic acid in olive oil is 3.5% - 21%10; but levels of erucic acid could not be established.

In direct contrast to the claim in the Educational Supplement that olive oil has potential for harm, a study11 looking at the effects of daily treatment with an olive oil/lanolin cream, applied to undamaged skin in preterm infants, showed that treatment with this cream lowered the risk of dermatitis and was superior to Bepanthen, a commonly used emollient.

Exploring the concept of fatty acids in vegetable oils

This information can be explored more deeply, by giving much more consideration to the chemistry behind the above percentages and what they mean in reality.  Vegetable oils contain free fatty acids, as well as triglycerols, which are fatty acids bound to a glycerol molecule. The figure often quoted as fatty acids present in any particular oil is the total percentage of triglycerols and free fatty acids. (For example, the main constituents of olive oil and sunflower oil, as quoted above, are the total levels of triglycerols and free fatty acids.) In a given quantity of extra virgin olive oil, the free fatty acid present is usually well under 0.8%10. The majority of fatty acids found in olive oil are bound to glycerol making them chemically less active.  Therefore, the measurement of total fatty acid content is not a true measure of the reactivity of an oil. A more accurate measure of an oil’s reactivity would be the amount of free fatty acid present. 

In the research papers reviewed,3^,4,5,6 the substance used is not natural olive oil but a fabricated solution of pure oleic acid (1% - 15%) dissolved in ethanol, propylene glycol or MYRITOL 318. The oleic acid solutions were applied to mouse, rat or human skin, which was usually tape-stripped before testing commenced; a treatment that is known to artificially compromise the epidermal barrier.  The solutions used in the studies therefore contained free fatty acid concentrations in excess of those found in natural olive oil. It is difficult, therefore, to draw direct conclusions with regard to natural olive oil from these studies.

Mineral oils

Regarding mineral oil and the suggestion that it is a much safer oil to use for massage and skincare, the articles1,2 in the supplement were interesting.  These ‘facts’ were actually more difficult to refute, as there seems to be extensive research that investigates unrefined or partially refined mineral oil, but searching the internet for information on refined  (or ‘medicinal grade’1) mineral oil proved to be fruitless.  There is a lot of confusion relating to the term ‘mineral oil’.  Published articles relating to unrefined mineral oil, indicate that it is carcinogenic.; but this has been taken to mean that all mineral oils are carcinogenic without taking into account the refining process.  It is easy to tar all mineral oil with the same brush, but that would openly invite criticism.  The educational supplement1, has drawn conclusions from the research about oleic acid, implicating olive oil as an ‘oil to avoid’ vis-à-vis infant skincare.  It is important not to have the same knee-jerk reaction to the research relating to mineral oil, but instead, assess the evidence supporting the arguments presented.

The supplement2 indicates that medicinal grade mineral oil should be used for infant skincare and massage because it does not contain oleic acid, is extremely inert and less likely to irritate the skin and, contrary to popular belief, it is able to penetrate the skin as well as a vegetable oil and therefore does not block the pores.  These statements, like others in the articles included in the supplement, are unreferenced.  There is no indication that there is any research to support these claims in the supplement and research for this review also failed to find any concrete evidence.

Furthermore, there is no explanation of what ‘medicinal grade mineral oil’ is.  If it is pure, unadulterated mineral oil, then the problem arises that this is not readily available over the counter.  It is actually quite difficult to obtain (several unsuccessful attempts to do so were undertaken as part of the process for this review) and it is generally only purchased in large quantities by cosmetic companies.  If ‘medicinal grade mineral oil’ refers to the oil that is widely available commercially, then, as it is mixed with at least a couple of additives, the question has to be, how can this be beneficial for an infant’s skin?

Having investigated the ingredients of three commercially available mineral oils, which are specifically marketed for use with babies, the following chemicals were found: Hexyl laurate, hydrogenated styrene and cyclopentasiloxane, which are all chemical ingredients, commonly used by the cosmetic industry.  One product sample included Prunus dulcis, which is the Latin name for the almond tree.  Lavandula angustifolio, found in another, is the Latin name for Lavender; and Bisabolol, found in one of the samples, is the main active ingredient in Chamomile essential oil; and Chamomilla recutita, found in another, is the Latin name for Chamomile. They also all contained ‘Parfum’, which is perfume, but what perfume was used and what it contains was not specified.

Firstly, the question, ‘Why put unnecessary chemicals on a baby’s skin?’ has to be asked.  Why let them potentially ingest, or absorb ingredients that are of no benefit to them?  Furthermore, there is research12 to indicate that essential oils are potential endocrine disruptors and that they should be avoided for prepubescent children.  If a product is being applied regularly, over a sustained period of time, there is a greater chance of an effect occurring.  Particularly in the case of infant massage, parents are encouraged to massage as often as possible (preferably every day), until their infant is at least crawling, but preferably beyond8.

Having reviewed the Educational Supplement, ‘Infant Skincare’, and the associated research papers, it is difficult to draw a clear conclusion that olive oil per se is harmful to the skin and that mineral oil is beneficial.  With specific reference to infant massage, sunflower, grapeseed and fractionated coconut oils are considered the most suitable8, but olive oil is recognised as a safe alternative, particularly when mixed with a lighter oil, such as sunflower8. This would have the further effect of reducing the already low levels of free fatty acids present in olive oil.  In addition, as the contraindications to massage include infectious skin conditions, open, weeping wounds and rashes (i.e. if the skin is damaged in any way), such application should not occur and the safeguarding of the infants’ (skin) health would be assured.

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[1] Introduction by Fergie, G. (2010) Infant Skincare: Common Myths about Baby Skincare.  Community Practitioner - Educational Supplement.  2: 4-5

[2] Introduction by Fergie, G. (2010) Infant Skincare: Implications for Practice.  Community Practitioner - Educational Supplement.  2: 10

[3] Mélot, M., Pudney, P.D.A., Williamson, AM. & Caspers, P.J. (2009) Studying the effectiveness of penetration enhancers to deliver retinol through the stratum corneum by in vivo confocal Raman spectroscopy. Journal of Controlled Release. 138: 32-39

[4] Naik, A., Pechtold, L., Potts, R.O. & Guy, R.H. (1995) Mechanism of oleic acid-induced skin penetration enhancement in vivo in humans. Journal of Controlled Release. 37: 299-306

[5] Jiang, S.J. & Zhou, X.J. (2003) Examination of the Mechanism of Oleic Acid-Induced Percutaneous Penetration Enhancement: an Ultrastructural Study. Biol. Pharm. Bull. 26(1): 66-68

[6] Larrucea, E., Arellano, A., Santoyo, S. & Ygartua, P. (2001) Combined effect of oleic acid and propylene glycol on the percutaneous penetration of tenoxicam and its retention in the skin. European Journal of Pharmaceutics and Biopharmaceutics. 52: 113-119

[7] Darmstadt, G.L., Mao-Qiang, M., Chi, E., Saha, S.K., Ziboh, V.A., Black, R.E., Santosham, M. & Elias, P.M. (2002) Impact of topical Oils on the Skin Barrier: Possible Implications for Neonatal Health in Developing Countries.  Acta Paediatr. 91: 546-554

8 Carpenter, P. & Epple, A. (2009) Infant Massage: The Definitive Guide to Teaching Parents.  Ditto International Ltd.

9 www.sunflowerguide.com

10 www.oliveoilsource.com

11 Kiechl-Kohlendorfer et al. (2008) The effect of daily treatment with an olive oil/lanolin emollient on skin integrity in preterm infants: a randomized controlled trial. Pediatr Dermatol. 25(2): 174-8

12 Henley, D.V. & Karach (2007)  Prepubertal Gynecomastia Linked to Lavender and Tea Tree Oils. The New England Journal of Medicine. 356: 479-485

Chemical structures:

For clear information about the chemical structures of oleic acid see:

·         http://www.scientificpsychic.com/fitness/fattyacids1.html

·         http://www.oliveoilsource.com/page/chemical-characteristics

Henley’s Essential Oil Research Analysing The Arguments Against The Research Findings

 Connections, Autumn 2007

The Henley and Karach research that indicates that lavender and tea tree oils cause an imbalance in oestrogen and androgen pathway signalling, has certainly awoken the world of aromatherapy. A loud and
immediate ‘call to arms’ resulted in a huge number of retorts and criticisms being levelled at the study.
I decided to trawl the internet after receiving one or two emails about my article on the matter, printed in the
last Connections newsletter. Wow! I was amazed at the amount of criticism of the study that I found and
had to at once consider that I might have been hasty in my decision to take this study on face value. However, I worked my way through several of the articles and blogs that I found and soon felt assured that my decision to err on the side of caution with regard to essential oils should, and will, remain firm.

The majority of the criticism was directed at the case studies of the three boys who developed gynaecomastia. These opposing arguments I found were generally based around one of the following:The other components of these products that contained the oil/s were not considered – how do they know that it was particularly the essential oil that caused the gynaecomastia?  􀂾 How could they possibly know it was the essential oil/s – the boys could have ingested or absorbed soy or parabens, or one of the many other products that have proved to be endocrine disruptors?  How can three cases be representative of the
wider population?  As the case studies were all from the same area, shouldn’t consideration be given to
environmental factors?


Yes, soy and parabens etc are endocrine disruptors and potentially could have been ingested or absorbed by the three boys with gynaecomastia (though apparently Bloch interviewed the boys and their parents carefully
and these products were ruled out). Yes, there were only three case studies mentioned and all from the
same area in the USA. But, these arguments all miss the point; Henley and Karach’s research was not about
the three case studies per say. Bloch, the boys’ paediatric endocrinologist, passed the information on to
Henley and Karach at the National Institute of Environmental Health Sciences in Research (USA), who
both felt it worthy of investigation. The boys’ medical condition simply set off an alarm bell that acted as a
springboard activating the research itself – which ultimately took place in a laboratory.  The laboratory experiments that followed, indicated that when exposed to lavender and/or tea tree, human breast cells turned on oestrogen-regulated genes and inhibited an androgen-regulated gene. Once tested they clearly fell into the same bracket as soy, parabens, etc – i.e. they have the same potential as endocrine disruptors.

I am not an aromatherapist and would not try to dictate to someone who is that they should not be using
essential oils as a therapy. But the majority of the GICM members, in our capacity as infant massage teachers are not offering therapy. We are trying to encourage parents to massage their baby and growing child, if not daily, at least three or four times a week. The use of an essential oil as a treatment for a particular condition, such as relief for the itching that accompanies chicken pox is one thing, but for parents to regularly, over a sustained period of time, use a massage medium containing essential oils is another. Yes, it is a parent’s prerogative to use whatever massage medium they see fit to use; and I would never ‘tell’ them not to. However, where oils are concerned, we have the opportunity to advise and suggest without being dictatorial; and I will continue to let parents know what I now know, so they can at least make an informed decision about this.

Music, Movement and Rhyme: The Essentials for the Developing Child

Today's Therapist Sept/Oct 2007

There are many benefits to be gained from singing rhymes with babies and children whilst encouraging them to do simple exercises in time to the rhythm of the songs.  Not only can singing and movement enhance a child’s overall development, it can be fun and enhances communication between parents and their baby because it gives them the opportunity to watch and learn about their growing child.  As communication, understanding and respect are enhanced, so too is the parent-child bond. 

A BABY’S NEED FOR MOVEMENT

Primitive Reflexes

At birth a baby’s motor development is immature, so initially they rely on a set of basic primitive reflexes to assist them in the early stages of their life. Primitive reflexes require no frontal brain (thought process) activity; as they are activated from the brainstem, which creates a specific, automatic response.  These reflexes are essential for helping a baby through the birth, as well as for survival in the first few weeks of life and are progressively integrated into movements that help them through some early developmental stages (Goddard-Blythe, 2005).  For example, the Tonic Labyrinthine Reflex supports the early stages of head control, balance and postural stability; the Asymmetrical Tonic Neck reflex assists early reaching movements; and the Babinski Reflex helps with commando crawling.

Postural Reflexes

As a baby’s motor development improves, the primitive reflexes gradually become inhibited and are replaced by postural reflexes; which help them to balance and coordinate their body (Goddard-Blythe, 2005).  These reflexes will remain with the child for life.  The ability to balance is largely due to the vestibular system, which is situated in the inner ear.  Movement stimulates the vestibular system and in the early months of life this greatly contributes to the necessary development of motor skills (Goddard-Blythe, 2005).

The more a baby has the opportunity to move, the more they will develop muscle strength and tone, which is also important to help a child balance and coordinate properly (Goddard-Blythe, 2005), so that they can eventually stand and walk and manage the world around them.  The more a baby has the opportunity to move freely and to experience the world from many different dimensions (such as moving round in circles, up and down, from side to side as well as backwards and forwards), greater is their ability to take control of their movements; and the development of postural reflexes will be enhanced.

If a child does not pass through each of the developmental milestones (sitting, rolling over, commando crawling, crawling on all fours, standing, walking) the postural reflexes may remain under-developed (Goddard-Blythe, 2005).  This could be detrimental to the developing child, who may struggle to socialise or build relationships; and they may have emotional issues and learning difficulties later in life (Goddard-Blythe, 2005).

The cross-lateral movements used at the crawling stages are not only vital to help inhibit primitive reflexes and develop postural ones: they will also help general brain development, particularly in relation to the child’s ability to read when they reach school age (Marshall, 1999).  This is because this type of movement supports the development of the corpus callosum, which connects the two hemispheres of the brain – thus encouraging greater cooperation between both sides of the brain (Hannaford, 1995).

 

THE NEED FOR MUSIC, SINGING AND RHYME

In light of the fact that music forms part of the structure of a society; and nursery rhymes form part of a culture’s linguistic customs and traditions, it is not surprising to find that music is considered to be crucial for a child’s social development (Cross, 2005).

Communicating From Birth

From birth, a baby is capable of communicating and actually becoming involved in a dialogue that involves turn-taking; much as a conversation between adults does.  In particular, a baby enjoys ‘chatting’ with their mother, whose voice is familiar to them because they became used to (and biased towards) their voice whilst in the womb (Welsh, 2005); and because it is the right pitch and melody to keep the baby interested in a ‘conversation’ (Trevarthen & Malloch, 2002; Welsh, 2005).  It is important that a baby is able to see and hear the person singing or speaking to them, which tends to prompt them to become more attentive and calm (Welsh, 2005).  This ultimately enhances the infant-parent interaction (Sawyer, 2005), because whilst taking time to ‘chat’ or sing, parent’s will have the opportunity to increase their understanding of their baby’s cues; and the baby will be able to learn from the experience as they start to interpret their parents’ emotions and behaviour towards them. 

Dysfunctional Interaction?

However, issues arise for mothers with postnatal illness, as they tend to have quieter, lower pitched voices and are less inclined to observe and follow the turn-taking ‘rules’ of a conversation.  Generally the pause between the mother’s speech and the baby’s is longer than the baby is attuned to and prefers (Welsh, 2005).

Singing nursery rhymes may potentially help overcome this situation, as the majority of rhymes need to be sung in a higher pitch than normal, as well as at a specific (usually upbeat) speed and tempo.

Some parents do not have depression, but still feel uncomfortable ‘chatting’ to their baby.  This is unfortunate, as it affects the child’s potential; in particular language development and social ability.  Encouraging parents to sing to their baby overcomes their need to think about what to ‘say’ to them.

Linking Music And Speech

Both music and language are considered to be ‘communicative mediums’ (Cross, 2005). Generally, communication between a parent and baby is musical or ‘proto-musical’ (Cross, 2005) by nature because it includes pitch contours, rhythmical timing, turn-taking and links sound and movement.  There is more than a notable connection between music and speech (Sawyer, 2005), particularly as the strong timing and rhythmic elements of music impact on the speech centres in the brain (Thaut, 2005).  Babies have the ability to imitate simple rhythms long before they develop speech (Goddard-Blythe, 2005).  A baby’s babbling has pitch, tone and rhythm - all of which are key elements of music and are deeply entwined with early language development (Cross, 2005). 

Singing And Speech

Adults generally tend to distinguish between ‘speech’ and ‘singing’, but babies and young children tend not to make this distinction (Welsh, 2005).   When ‘chatting’, babies will imitate the tone and tempo of adult speech, long before they can talk.  The sound of this ‘chatting’ is usually melodious, as if they are singing or humming a song (Goddard-Blythe, 2005).  From a developmental point of view, this is the fledging stages of a child’s vocabulary bank forming (Welsh, 2005).

In response to a baby’s need to sing when ‘chatting’, it is common for parents to reply accordingly, using, what is known as, infant-directed speech (‘motherese’ or ‘parentese’).  Infant-directed speech is, in fact, very similar to the singing of lullabies and nursery rhymes; because the acoustic features tend to be simple, repetitive, higher pitched than usual speech and expressive (Welsh, 2005).

Music, Singing And Child Development

Music and singing can be very positive for a young child’s overall development.  It can affect the overall functioning of the nervous, endocrine and immune systems (Thurman & Welsh, 2000).  Music, in particular, also contributes to brain development, as it is a powerful tool for supporting learning and develops left-hemisphere abilities, and the development of the inner ear and links motor skills, sounds and visual images that are essential for reading and writing skills (Goddard-Blythe, 2005).  Also, the critical aspects of timing and sequencing within music and rhyme may positively affect a child’s attention and their ability to make decisions (Thaut, 2005); and can enhance short-term memory because of the repetitive nature of singing (Goddard-Blythe, 2005). 

RHYTHM – A COMBINATION OF MUSIC AND MOVEMENT

Although it is possible to experience music in isolation and movement without music, often one enhances the other.  Imagine how difficult it would be to stay perfectly still whilst a favourite piece of music or song was playing?  Or, how much easier an aerobics class is when there is music and song to assist the timing of the exercises.   This is because music and singing impact on the sensory systems in the brain that control the timing, sequencing and co-ordination of movement (Thaut, 2005).  Furthermore, sounds have the capacity to stimulate the spinal motor neurons at the brainstem and spinal cord level.  This promotes a state of readiness for the execution of movement (Thaut, 2005).

The repetitive element of singing rhymes is enhanced when accompanied by rhythmical exercises, which can help a child retain their flexibility, gain strength and improve muscle tone; as well as potentially enhancing the development of co-ordination and balance.  Joining a class to enjoy the benefits of rhyme and exercise gives the opportunity for parents to sing in a group, which can reduce stress hormones and muscle tension and help the heart rate normalise.  Also, combining rhymes and exercise for children gives the parent and child time together to just have some ‘fun’!

Pauline Carpenter is the Chair for the Guild of Infant and Child Massage www.gicm.org.uk and a Director of Touch-Learn Ltd.  www.touchlearn.co.uk , a training company offering infant massage and Rhythm Kids™ music and movement teacher training courses.  Pauline has also co-authored ‘Teach Yourself Baby Massage And Yoga’ and ‘Rhythm Kids: Fun Time Exercises for Babies’.

References

Cross, I. (2005) Music And Meaning, Ambiguity And Evolution  In Miell, D. MacDonald, R. & Hargreaves, D.J. Musical Communication  Oxford University Press  Oxford

Goddard-Blythe, S. (2005)  The Well Balanced Child  Hawthorn Press  Stroud

Hannaford, C. (1995) Smart Moves: Why Not All Learning Is In Your Head Great Ocean Publishers US

Marshall, C. (1999)  Reading and Writing and…….. PMEA News, cited on www.menc.org/networks/genmus/litarticles.html

Sawyer, R.K. (2005) Music And Conversation  In Miell, D. MacDonald, R. & Hargreaves, D.J. Musical Communication  Oxford University Press  Oxford

Thaut, M.H. (2005)  Rhythm, Human Temporality, And Brain Function  In Miell, D. MacDonald, R. & Hargreaves, D.J.  Musical Communication  Oxford University Press  Oxford

Trevarthen, C. & Malloch, S.  (2002)  Musicality And Music Before Three: Human Vitality And Invention Shared With Pride  Zero to Three  Vol. 23  No. 1

Welsh, G.F. (2005)  Singing As Communication  In Miell, D. MacDonald, R. & Hargreaves, D.J.  Musical Communication  Oxford University Press  Oxford