Skin Physiology and Dry Skin

Introduction

Skin is considered to be the largest organ of the human body, accounting for 12-15% of body weight and covering 1.5 to 2 square metres of area.¹  It is a highly dynamic and complex organ with a large number of specific roles.  Aside from providing a key physical barrier to the outside world, it is also the site of significant endocrine, immunological and metabolic function.  The skin forms part of the vital communication network between the inside and outside world.

But even this is only half the story.  The skin is not only an indispensable biological organ, but also functions as a social organ.  It plays an important cosmetic role with a significant impact on one’s social interactions, confidence, body-image, job prospects and even mate selection.  Skin is often, rightly or wrongly, also used crudely as a surrogate marker for the perception of an individual’s general health status.

To be able to develop and formulate personal care products to supplement the skin and its numerous processes, it is important to have a solid understanding of the skin’s structure and function in both health and compromised or pathological states.  The aims of this essay are to discuss basic skin physiology and maintenance of skin barrier health, and how the latter can be achieved.  There will be a focus on how the skin behaves in a dry or dehydrated state and the impact of chemical agents that may drive these.  Finally, strategies such as moisturisers and their selection will be reviewed as a method of breaking the dry-skin cycle and enhancing skin barrier function.

1)        Skin Structure and Function

The skin has three main layers each with its own primary function²:

• the epidermis, which functions as a barrier preventing loss of fluid and electrolytes as well as offering protection against external insult or injury;
• the dermis, which is the source of structural and nutritional support; and
• the hypodermis or subcutaneous fat layer, which offers insulation

Whilst skin structure under light microscopy is fairly consistent in most body regions, there are well-recognised modifications in specialized areas such as the palms, soles, genitalia and scalp.  Skin thickness can vary across sites with the epidermis of the eyelid measuring 0.05mm in contrast with the palms at 1.5mm.³

1a) The Epidermis

The epidermis is the outermost layer of skin and its main cell type is the keratinocyte, which account for 90-95% of cells.  They are key in forming a physical, biological and chemical barrier to the outside world, offering thermal protection as well as keeping out pollution, microbes and allergens. In addition, they are a key site for vitamin D production.

The epidermis is arranged in stratified layers to include the basal layer (stratum basale), spinous layer (stratum spinosum), granular layer (stratum granulosum) and finally the stratum corneum.   In certain areas where the skin is thick (e.g. acral sites such as the palms and soles), there is an additional layer known as the stratum lucidum which sits between the stratum granulosum and stratum spinosum.

In contrast to the other layers, the stratum corneum consists of anucleated cells called corneocytes, which are derived from keratinocytes.  Cells from the basal layer migrate and differentiate upwards until they form the stratum corneum.  Dead cells are sloughed from the surface in a process known as desquamation.  Under normal conditions, it takes two weeks for differentiating cells to leave the nucleated compartment and a further two weeks to move through the layers of the stratum corneum.  The skin will therefore renew itself every 28 days.²

The other main cells of the epidermis include melanocytes, Langerhans cells and Merkel cells.  Melanocytes are the pigment-producing cells of the skin.  There is approximately one melanocyte for 36-40 keratinocytes.  They are found in the basal layer of the skin where they make pigment granules known as melanosomes which contain melanin.³  These are transferred via dendritic processes to keratinocytes where they usually aggregate above the cell’s nucleus. Melanin is responsible for skin colour in addition to playing a major role in protecting the skin from ultraviolet radiation.

Langerhans cells are the third major resident cell type of the epidermis and play an important role in immune surveillance.  They metabolize complex antigenic substances into peptides and, once activated, migrate out of the epidermis into regional lymph nodes, functioning as antigen-presenting cells involved in immunity.  The final group of cells are the Merkel cells which act as mechanoreceptors responsible for light touch sensation.²

1b) The Dermis

Beneath the epidermis is a specialized structure known as the basement membrane, which attaches it to the next major layer, the dermis.  The dermis is highly vascularized providing both structural and nutritional support to the skin.  Its main cell type is the fibroblast which synthesizes collagen and elastin.^2,3

The dermis can sometimes be further classified into the papillary (upper) and reticular (lower) dermis.  The papillary dermis is rich in nerve fibres for detection of temperature, pain and itch sensation.  The reticular dermis contains a densely packed matrix of collagen and elastin fibres alongside a glycosaminoglycan gel.  These act together to give the skin strength, elasticity, and firmness.

Blood vessels in the dermis play a key role in transport of nutrients and removal of waste products in addition to thermoregulation.  A rise in body temperature triggers the dilation of blood vessels in the skin allowing heat to be lost from the surface; the opposite, constriction, occurs in cold weather in order to conserve heat.

In addition to contributing to the skin’s tensile strength, the dermis is the site of key adnexal structures such as the hair follicles, sebaceous glands, apocrine and eccrine glands.  These specialized tissues play unique roles in the skin.

Hair follicles are found all over the body except at the acral sites.  Sebaceous glands are also attached to hair follicles and, collectively, a hair follicle, its associated arrector pili muscle and sebaceous gland are known as the pilosebaceous unit.  Sebaceous glands produce sebum under the control of androgen hormones (e.g. testosterone, dihydrotestosterone) to act as a lubricant for skin.  In response to cold or strong emotions such as fear, a contraction of the follicle’s arrector pili muscles occurs, which causes the hair to stand up on end.

Eccrine sweat glands can be found all over the body but occur in highest density in the axillae, forehead and acral sites.  These aid temperature regulation; when the body needs to lose heat it will product sweat which evaporates from the skin surface causing cooling.  Sweat also functions to facilitate excrete organic toxins and heavy metals.

Lastly, the apocrine glands – found primarily in the axillae and anogenital region – secrete a viscous, milky, odourless fluid thought to provide pheromone-like activity.

1c) The Hypodermis

The subcutaneous layer of skin consists primarily of adipocytes.  It functions to absorb shock thereby offering mechanical protection in addition to insulation.  Its thickness can vary depending on body site.

1d) Summary of Function of Skin

As outlined above, the skin has a number of important functions facilitated by its unique structure and resident cell types.

Function	Structure
Barrier	Stratum corneum
Endocrine	Vitamin D production in keratinocytes
Immunological	Langerhans cells
Sensation	Merkel Cells
Thermoregulation	Eccrine sweat glands, dermal blood vessels
Photoprotection	Melanocytes
Waterproofing and lubrication	Sebaceous glands
Heat insulation and protection from mechanical injury	Subcutaneous fat

2) Understanding Healthy Skin

Maintaining a healthy skin barrier is largely dependent on the process of desquamation in the epidermis.  It will take approximately 28 days for a keratinocyte to migrate and differentiate from the basal layer and eventually be shed from the stratum corneum.

Keratinocytes in the basal layer are the only viable cells of the epidermis.  As they travel upwards, they start to lose the ability to undergo mitosis.  As keratinocytes differentiate into spinous layer cells their shape becomes more polyhedral.  Individual cells are held together by proteins known as desmosomes which require calcium-dependent enzymes for their formation.  As the cells migrate into the granular layer, they contain keratohyalin granules which consist of proteins (e.g. profilaggrin, loricrin, involucrin, envoplakin) which will eventually form the cornified envelope of the stratum corneum.  The cells finally move into the stratum corneum losing their nucleus, other organelles and plasma membrane.  Desmosome attachments become weaker and the cells are ultimately sloughed away from the surface.⁴

Skin disease can occur when this process is disrupted.  Decreased shedding of skin cells from the surface will result in ichthyosis; increased epidermal cell turnover results in psoriasis.  Impaired barrier function can be seen in Darier disease as a result of mutations in the ATP-dependent calcium pump in the epidermis.

Dry skin

One of the main functions of the epidermis is to prevent water loss and maintain hydration of the skin.  Disruption of the barrier can result in increased water loss (known as trans-epidermal water loss, TEWL) and dry skin. Cosmetically dry skin has been noted to have a weaker barrier function than normal skin.  Impaired desquamation can lead to lower cohesivity of skin cells and dry skin has been shown to contain lower natural moisturising factors.  Reduced barrier function will also facilitate the absorption of products being applied to the skin surface resulting in irritant contact dermatitis. Pathogens and allergens may, additionally, enter the skin more easily.⁵

Dry skin on a macroscopic level can appear rough, uneven, flaky, and even fissured.  Symptomatically, the skin may feel dry, tight, uncomfortable, painful or itchy.  Individual or environmental factors may also work together to produce dryness.  Underlying skin disorders (e.g. atopic dermatitis) and increased age as well as low humidity and temperature, exposure to solvents and some surfactants may contribute to dryness.⁶

Prolonged use of soaps and surfactants can have a negative impact on the skin barrier.  They can emulsify lipids and denature proteins found in the skin, increasing both TEWL and its permeability.  Anionic surfactants tend to be the most problematic (e.g. C10-C12 alkyl chains, alkyl sulphates) in contrast to amphoteric surfactants which have a better safety profile.

In addition to changing the water and skin surface chemistry, irritants may also potentially alter the natural microbial flora of the skin.  Certain bacteria have been linked to higher rates of growth in alkaline pH and may have the ability to displace the normal skin microbiome.⁷

3) The Stratum Corneum and Methods for Studying Barrier Function

Despite consisting of non-viable cells, the stratum corneum plays several key functions.  Not only is it responsible for skin hydration, it functions as the mechanical and permeability barrier, in addition to keeping out reactive oxygen species from the environment, UV from sunlight, and microbes.

The stratum corneum is 12-16 layers thick.  Its overall structure is of a “bricks and mortar” configuration where the corneocytes form the bricks, and the mortar is composed of intercellular lipids.  The interaction between the two is responsible for the stratum corneum to function effectively as a particle and moisture barrier.  The very outer layer of the stratum corneum has a slightly acidic pH of 4.5 to 6.5 (sometimes known as the acid mantle) due to sebaceous and sweat gland secretion.  The acidic pH has antimicrobial properties.⁸

Corneocytes are flat and hexagonal in structure and packed in layers.  They contain the protein keratin, which binds water, in addition to a second protein known as filaggrin.  They have a cornified envelope rather than a plasma membrane and are connected to each other via corneodesmosomes.^2,8

Natural moisturising factors and intercellular lipids (ceramides, cholesterol and free fatty acids in a ratio of 3:1:1) are arranged in bilayers surrounding the corneocytes.  They are formed in the granular layer of the skin and their hydrophobic properties prevent water loss into the environment.⁸

Moisture homeostasis in the stratum corneum is maintained by natural moisturisation factors and desquamation. Moisture is also important in controlling the rate of desquamation.  In dry conditions, desmosomes remain intact resulting in a build-up of corneocytes and thickening of the stratum corneum.  This will be visible as scaly skin.

There are a number of methods by which stratum corneum barrier function can be measured, classified into physical, instrumental and biological.⁵

The physical method typically includes tape stripping or stripping of the stratum corneum using cyanoacrylate glue.  Microscopy is then used to visualise, and directly quantify, the cells removed.  This method is useful in assessing the quality and efficacy of skincare formulations.

Instrumental methods include measuring TEWL directly using an evaporimeter or inferentially via the skin’s electrical properties (e.g., using Corneometer or SkinChip technology).  Other methods measure epidermal thickness using confocal microscopy or, in the research setting, MRI (which can be helpful in providing information on the internal structures of the epidermis and observing improvements with treatment).^5,9

Biological methods to look at ultrastructural details of the stratum corneum and intercellular spaces utilize transmission electron microscopy, field emission scanning electron microscopy and immunofluorescence confocal laser scanning microscopy.⁵

4) Product Formulation Strategies for Dry Skin

Moisturisers are an important part of daily skincare and their main goals are to maintain skin integrity, improve appearance by retaining water content, preventing TEWL and assisting the skin’s natural barrier repair mechanism.  Clinical signs of dry skin (xerosis) will appear when the water content of the stratum corneum falls below 10%.⁵

There are many choices available for the components of a moisturiser formulation.  Not only does the product need to support natural skin desquamation and maintain a healthy barrier, it also needs to reach a high aesthetic standard acceptable for consumer use.  The basic components will usually consist of moisturising agents, water, emulsifier and preservatives.  Most day moisturisers will comprise oil in water emulsions, which are light and spread easily.¹⁰

There are three main classes of moisturising ingredients: occlusives, humectants and emollients.  A well-designed moisturising product for damaged or dehydrated skin will contain a combination of these classes of ingredient for best outcome.⁶

Occlusive agents prevent TEWL by forming a hydrophobic barrier or film over the skin surface, which reduces evaporation from the statum corneum.  Common examples include petrolatum, lanolin and beeswax.  Petrolatum is highly effective but has an unfavourable “greasy” texture.  Lanolin use is generally limited due to its odour and allergenicity.^6,10,11

Humectants attract water from the viable epidermis and dermis (and also the environment if humidity is above 80%), which functions to increase corneocyte water content and promote normal desquamation.  Glycerin, sorbitol, urea and sodium lactate are all examples of topically-applied humectants.  Glycerin, in particular, is one of the most commonly used compounds in cosmetic formulations and can be used in a range of different product types including sticks, micro-emulsions and creams.

The third and final class is the emollients which work by filling in the gaps or spaces between the corneocytes and thereby smoothening the appearance of rough skin.  They are usually lipids or oils which repel polar water molecules and limit their passage to the outer environment.  Depending on their inherent properties they can be further classified into protective, fatting, astringent or dry sub-types.

A good moisturiser may also contain special additives such as hydroxy acids, UV filters, vitamins, essential fatty acids and botanical agents depending on the desired end result.  Thought must also be given to the medium by which active ingredients are delivered to the stratum corneum (e.g. cyclodextrins, liposomes).  Fragrance may be added to mask the odour of other ingredients or to improve the overall aesthetic quality of the product.  Preservatives are essential to inhibit microbial growth and prevent lipids in the formulation becoming rancid.^11,12

Moisturisers will also require an appropriate emulsifier system to create cosmetically-elegant products.  Non-ionic emulsifiers are usually the most common type used in skin care products.  These include compounds such as alkoxylated alcohols, fatty acid ethoxylates, and glycol esters.^4,12

Creating compounds with a balance of the above components will result in a moisturiser that will help restore water content as well as improve skin barrier function in skin which has become damaged or dehydrated.

5) Helping the Consumer Choose a Moisturiser

There is no doubt the product market is heavily saturated and helping the consumer pick the right moisturiser for their skin needs is vital.  Descriptor terms such as the following may help:

• Reduce dryness
• Improve dull appearance
• Smooth and soften skin
• Increase firmness or suppleness
• Immediate comfort
• Long-lasting effect
• Nourishing
• Non-greasy

 

The challenge remains for a cosmetic formulator to deliver a product which is effective, causing minimal irritancy or allergenicity, with a minimal presence and pleasant aesthetic or sensory qualities.

Summary

The skin is a highly dynamic organ and not simply an inert brick wall despite the analogy so often used about its “bricks and mortar” structure.  Keratinocytes undergo many changes as they migrate and differentiate from the basal layer to the stratum corneum where they are ultimately shed.  The stratum corneum permeability barrier is composed of the cellular protein matrix as well as the intercellular lipids.  Both components are integral to maintaining desquamation, epidermal hydration and overall skin barrier function.

Moisturisers can be a useful way of managing damaged or dehydrated skin.  If they are well-formulated, they can reduce the impact of both internal and external factors (e.g. prolonged use of harsh surfactants) on stratum corneum permeability.  They will also aid the self-repair mechanism of the skin by ensuring water content remains at a level sufficient for normal enzymatic function and desquamation to continue.  Special additive ingredients can be used to fine-tune products for specific skincare concerns.

Guiding the consumer when the product is ready to market by appropriate terminology can help make individuals make informed choices about product selection.  Choosing the right product for the right concern will ultimately enhance the benefit of the treatment.

References

1. Martini & Nath: “Fundamentals of Anatomy & Physiology” 8th Edition, Pearson Education (2009), pp153.
2. T Vandergriff, Anatomy and Physiology in Dermatology, Bolognia J ed. Elsevier Ltd (2018) pp 44-55.
3. Bardia Amirlak, Skin Anatomy, Medscape website, available at https://emedicine.medscape.com/article/1294744-overview (accessed 18 Nov, 2019)
4. Lee T, Friedman A. Skin barrier health: Regulation and repair of the stratum corneum and the role of over-the-counter skincare.  J Drugs Dermatol 2016; 15(9): 1047-1051.
5. S Pillai, M Manco, C Oresajo. Epidermal Barrier in Cosmetic Dermatology – Products and Procedures, Draelos Z, ed.  Blackwell Publishing (2016) pp 3 – 11.
6. Loden M. Do moisturisers work?  Journal of Cosmetic Dermatology, 2, 141-149.
7. Grice E, Segre J. The skin microbiome.  Nature Reviews Microbiology 2011;9: 244-253.
8. B Dasgupta, J Bajor, D Mazzatti, M Misra. Cosmeceuticals: Function and the Skin Barrier in Cosmeceuticals, Draelos Z ed.  Elsevier Canada (2016) pp 3-11.
9. G Grove, J Damia, T Houser, C Zerweck, Evaluating Cosmeceutical Efficacy in Cosmeceuticals, Draelos Z ed. Elsevier Canada (2016) pp 21-25.
10. Rawlings AV, Harding CR. Moisturisation and skin barrier function.  Dermatol Ther 2004; 17 Suppl 1: 43-48.
11. Y Appa. Facial Moisturisers, in Cosmetic Dermatology – Products and Procedures, Draelos Z, ed.  Blackwell Publishing, UK (2016) pp 132-137.
12. J Del Rosso. Moisturiser and Barrier Repair Formulations in Cosmeceuticals, Draelos Z ed.  Elsevier Canada (2016) pp 81-89.

Clean Beauty

Why does everything need to be “clean” these days?  The concept of clean eating most certainly isn’t a new one and in the circles that I keep is firmly falling out of favour – and with very good reason may I add.  But “clean beauty” seems to keep hitting my radar and despite my personal beliefs about skincare, looks like it’s here to stay.  It is quite clear that beauty industry trends are simply providing what the consumer wants – a concoction of plant-based goodies for us to smear ourselves in, devoid of those toxic chemicals.  You know the ones?  The “nasties” that cause cancer and disrupt our hormones. Supposedly, anyway.

But what is the problem with this?  Why is it something that i inherently feel uncomfortable with?  I like to question my belief structure and do so frequently in an effort to drill down what exactly I have an issue with.  It is a better position to be in than stubbornly dogmatic and close-minded.  

I think a good place to start is to try and define what “clean beauty”.  Well, technically there’s no set definition but it is largely taken to mean one or more of the following: products which are natural or organic, products lacking synthetic preservatives such as parabens, and more recently the “suspicious 6” entered my frame of reference.  On the surface, there is no harm in removing certain ingredients from skincare and replacing it with others which are seen as “clean” by the general public, but is this highlighting a symptom of a much wider problem we have in society surrounding our health?

Why do chemicals have such a bad rep anyway?  On its most fundamental level, everything is a chemical.  Water is a chemical; we are a walking, talking mish-mash of chemicals, so why the fear?  Where did science lose its way in connecting with the masses that we are now in a strange post-truth world where even beauty is viewed as clean or dirty?  Well, I think the first thing that we need to understand is the concept of safety in beauty.  The EU has very strict guidelines on what chemicals can be used in our skincare and at what doses or concentrations.  These vary depending on whether a product is “leave on” e.g. a moisturiser or toner versus “rinse-off” e.g. a face wash.  For chemicals in general, it is the dose that makes the poison.  Many things are harmless to us in low doses (as found in our skincare or food) but dangerous in higher ones.  For example, formaldehyde is found in low doses in apples but this is not dangerous to our health.  You can be pretty certain that if a beauty product enters the market in the UK it is safe to our skin and general health due to rigorous industry regulation.

Despite this, the marketing phenomenon that is “clean beauty” is persuasive, compelling and people are buying into it in their droves.  We are being told that “clean” skincare must somehow be better for us.  We live in a world so fixated with “wellness” that society is in imminent danger of losing it’s ability as a group to grasp science or health literacy with their skin.  There is an element of virtue signalling amongst some of us and the company we keep that if we don’t care about the latest clean skin trend, we don’t care enough about ourselves or our families or that we aren’t a true “skintellectual”.  I often hear statements such as “all my skincare is natural” or “I only use organic products” or “I don’t use parabens” – but when did these become such a badge of honour?  

I think part of the problem comes from an inherent fear of what we don’t know or understand.  Seeing long chemical names on product labels can no doubt be confusing.  Combine this with the idea that if its from Mother Earth or natural it must somehow be better for you being driven by access to the internet, celebrity pages such as Goop and the general world of wellness we all live in.  Consumer demand has now got skincare to a place where cosmetic formulators, dermatologists and marketing teams are actively excluding ingredients not because they are bad for you but simply because people have got the wrong end of the stick about an ingredient (e.g. parabens) and it’s almost too much effort to change their mind and do the science education.  That in some ways is quite scary.  We are now making skincare for people based on their incorrect perception of an ingredient rather than the truth.  All this does is feed the lie or misconception rather than challenge the incorrect belief.  It truly is a post-truth world we live in.

Let’s look for example at a brand which has famously removed six “suspicious” ingredients from its products (essential oils, drying alcohols, silicones, chemical sunscreens, fragrance/dyes and SLS).  The implication is that somehow this range of ingredients is dangerous or toxic to the skin.  Sure, these ingredients have the potential to cause allergy or irritation in sensitive skin, but quite frankly any skincare product can do this, suspicious six or no suspicious six.  The company’s website states that regulations allow companies to include “harmful, disruptive ingredients” in their products (which obviously brand in question don’t use) – this simply isn’t true – the EU (for now) governs our cosmetics pretty carefully!  Swipe to read an interesting article in The Guardian discussing this further.

So just be aware:

1. Even plant-based skincare has chemicals in it.  Everything is made up of chemicals.
2. It is the dose or concentration that makes a chemical dangerous, not simply its presence in skincare.
3. “Non-toxic”, “clean”, “natural” and “safe” are all marketing terms when it comes to skincare.  They have no legal definition.
4. Your beauty products are not going to kill you. 

Why do we fear skin ageing?

Many of the pieces I write come from my own observations of patients attending my clinics. Since my very first dermatology job well over a decade ago I have seen probably thousands of people pass through my door and something has struck me particularly over the past twelve months. An increasing number of individuals in their early to mid-twenties seem preoccupied with premature skin ageing. I have had more requests than I can ever recall for those I would consider “young” expressing a desire to start an anti-ageing skincare routine or even have “preventative” Botox.  Many of them are not remotely showing signs of skin ageing such as fine lines, wrinkles, sagging or uneven skin tone yet their fear of looking old is incredibly real, sometimes bordering on unhealthy preoccupation.

Now I appreciate there may be a selection bias at play here in the nature of patients that come and see me.  I talk and write about skincare so naturally it makes up part of my practice.  Maybe I am simply seeing a skewed distribution of the population who are already more interested in skin ageing compared to the average person in the street.  It is also possible that as I creep nearer to the milestone that is 40, I am acutely aware of the ageing process myself and these patients tend to stick in my mind more.

Either way, this led to me thinking.  Whilst there is nothing wrong with “preventative” health and looking after your skin before problems develop, the million-dollar question is this – is skin ageing really a problem?  Is it a disease that we must prevent or treat or is it a normal part of getting old?

Why do we fear looking old so much?  We are literally ageing from the moment we draw our first breath.  Surely ageing is a blessing and not a curse.  Many do not have the luck of the draw and the option of living to a ripe old age.  So why do we desperately want to hide it?  Why is one of the biggest compliments you can pay an “older” woman that she looks young for her age. How have we ended up living in a society that effectively does not seem to value experience, which can only come with time, maturity and AGE.

I suspect the reasons are multiple.  There is no doubt a lack of representation of the ageing face in both the media and public eye.  After a certain age, it seem as if people – women in particular – seem to vanish from sight as they are replaced by a younger counterpart.  The subliminal message that is being delivered to women is that one needs to be young to be deemed successful and worthy of being seen.  Our idea of beauty remains limited and differences (not just in race but also age) are still not celebrated.  There are fewer visible “older” positive role models for us to see and aspire to being.

Or is it something deeper?  As we look in the mirror and see our grays multiply and laughter lines deepen, the visual cues of ageing can be a warning sign in our minds of impending ill-health and possible loss of independence as we inch closer to accepting our mortality. By trying to look younger are we trying to fool ourselves that we are successfully turning back the clock with that little bit of Botox or filler.  Even if our birthday tells us we are older, seeing a mismatch between our actual and perceived age could be a defense mechanism where we are refusing to accept the inevitability of death.

Seeing so many young people preoccupied with skin ageing begs me to ask the question, that are we as the beauty, aesthetics and cosmetic dermatology industry driving a society that is further conditioning us to believe that ageing is a burden or negative in our life we must fear.  And then conveniently offering us the magic solution in a pot of cream and latest skin tightening fad.

Gerascophobia.  A word that recently entered my radar when I was reflecting on my thoughts one rainy afternoon.  An abnormal or incessant fear of growing older or ageing.  This is a recognized clinical entity and a type of phobia.

Why do I bring it up?  Well, is it possible that years of using youth as a hallmark for beauty, success and desirability is leading to a generation of us that have low, grumbling levels of gerascophobia.  Not to the point of diagnosed clinical pathology but a spectrum that we may be on at population level?

We know that cosmetic procedures are increasing in young people but this week I’ve seen quite a few people in clinic who have been notably anxious about skin ageing and keen for preventative treatments.  Now this could simply be a subtype of body dysmorphia OR are we talking about an insidious low-grade fear of ageing that is drilled into us from a young age.

Many have cosmetic procedures to make themselves feel better.  They aren’t doing it for anyone else.  But what is it about looking younger or hiding our signs of ageing that makes us feel better?  This is what I am trying to drill down.  There is no judgement here, and I use retinol and have the occasional injectable treatment like many others.

What I do want to do though is make you think and encourage you to look at your own motivations.  Is getting old really that bad.  What are we actually scared of?  Are we all secretly worrying about the same thing – a perceived loss of power or respect? It is as simple as the patriarchy and living in a man’s world or is our skin ageing a stark reminder that our body is ageing too and our days may be numbered.  How do we put ourselves in a position where we can value the gift that is life and “age” in a way that is positive.

I’m not sure I have the answers and the thoughts I recognize are odd coming from a dermatologist who carries out treatments for skin ageing.  Everyone should have a choice about what they want to do to themselves but it is important to think about what motivates us. I don’t want to be driving an unhealthy fear of skin ageing in my patients or society as large.  I also want to see more representation of older, successful women that aren’t wiped off the radar once they get to a certain age. It is only when we see role models, can we aspire to be them without thinking it all comes down to how we look and our individual aesthetic.  We are all worthy and deserving of our lives regardless of our age, shape, size, colour or anything else people use to divide us.  Next time you look in the mirror and feel negative about your skin and it’s natural ageing process ask yourself, what is it that’s really bothering you about what you see.

 

 

 

Protein bars, whey and acne

As a woman in her mid to late 30s that is interested in healthy living, like many others, I do my best to eat, sleep and exercise well. I have always been slight and building muscle has always been a challenge. Over the years, I have had friends, (who also happen to be personal trainers) tell me repeatedly that it is down to my diet and not enough protein.

So over the years, I’ve done what I’m sure a lot of other women do too, and gone out one afternoon and come home with a box of whey protein powder and a various array of protein bars and snacks. Just the process of shopping for these items and seeing drawers full of them at home made me feel smugly virtuous and “healthy”.

Obviously, I did my research. I spent countless hours on the Internet reading about protein powders before I decided which one I should buy. For a newbie to supplements (I’ve always believed that if I eat and drink a balanced diet I shouldn’t need anything extra) I was amazed there was a choice: whey, casein, pea, rice, hemp. I decided that whey protein was the way forward, it seemed to have the highest protein content gram for gram as well as being easy to find and relatively cheap.

Whey protein powder and Bounce bars quickly became a staple if I was in a rush and missed a meal, before and after training, and generally as my “healthy” go-to snack in the middle of the day. So much for my life-long thoughts on eating and drinking everything in moderation; I was in a mind-set that protein was all I needed. (As an aside, my muscles still weren’t anywhere near the proportions I’ve always desired).

I’ll come back to the whey protein in a moment.

I also happen to be a dermatologist for a living. I am interested in everything skincare and beauty related. To top it off, I’ve had troublesome acne that I have failed to grow out of for at least 25 years. I would actually dare say, that my skin has been more resistant than any patient I have ever treated – and I am aware what a bold statement that is to make. Treatments work, it gets better, and 6 to 12 months later, the dreaded red giants are back. Whilst spots are never a good look for anyone, they definitely aren’t a good look for the doctor that’s meant to be treating them!

Female adult acne is common and consultations for this have been increasing over the past decade.   I am certainly seeing more adult women with acne now in my clinics than ever before. We all know that acne makes you feel bad and the emotional and psychological effects such as low self-esteem are well-recognised. There is an idea that adult women with acne may be more conscious of their skin problems because it is still considered a “teenage disease”. Grown women end up feeling unsupported and distressed wondering why they are still having breakouts when that part of their life has passed.

The other thing we know about adult women with acne is that there is a higher failure rate of the usual conventional treatments that we use. So, basically, there is a higher chance the treatment either won’t work OR that it will work but your spots will come back or relapse again further down the line. It becomes much more about trying to “control” acne rather than “cure” it for once and for all.

And, let’s face it, we all lead busy lives – we work long hours and we want a balance so we probably also play long hours too. Families, friends, exercise, work, down-time – it all has to fit in somewhere. Having a skin condition that you cannot control is incredibly frustrating and provokes anxiety. Anyone with bad acne will relate to waking up first thing in the morning and touching their face to see if any new monsters have appeared on their face overnight and that sickening feeling of dread when your worst fears are confirmed. Lack of control is frightening. So we desperately look to find something we can control that might make our skin disease better.

This comes to a question that is often raised with me in consultations about whether controlling diet will help spots. I have lost count of the times I have been asked whether going dairy-free will help. As a doctor and fellow acne sufferer, to answer this question honestly meant going back and reviewing all the scientific literature for myself. It’s not that I don’t trust anyone else’s opinion, but there’s nothing more important than reading and making decisions for yourself. So I sat down one weekend to find the answer. I have agreed to do a talk entitled “Diet and Acne” in May for a medical meeting, so effectively I was killing lots of birds with one stone, so to speak.

And what I found was extremely interesting. The relationship between the two has been highly controversial, but before the 1960s, dietary advice was a standard part of acne therapy. Dermatologists actively discouraged foods such as chocolate, fats, sweets, and fizzy drinks. Then in the late 60s and 70s two pivotal scientific studies came along suggesting the link did not exist. Diet was forgotten about for quite a long period of time, and certainly when I was training, I was taught that the whole diet-acne connection was a myth. But having read the studies and the research that came afterwards, those studies had major methodological errors.

What’s even more interesting is that certain population groups that follow “hunter-gatherer” diets, such as native populations in Papua New Guinea and Paraguay don’t suffer with acne. Other groups such as the Canadian Inuits and Zulus did not have acne until their diet became Westernised. Ok, so it’s not a hard and fast robust clinical trial, but nonetheless, an interesting observation.

There is no doubt that there is emerging evidence that diets that are high in processed carbohydrates (high glycaemic index) and dairy can be linked to the development of acne. At present, the link seems to be stronger with high GI foods than dairy itself but it’s there. Both types of food are thought to increase raised circulating blood sugar or glucose levels. Raised sugar in the blood stream causes your body to produce the hormone insulin and insulin-like growth factor (IGF-1). Both of these agents increase oil or sebum production and also encourage release of male hormones known as androgens (both men and women have these). A combination of these factors can drive acne production.

So let’s go back to where I started. What does this have to do with protein bars? Well, as I was tucking into my Bounce bar doing my research, the penny suddenly dropped that I was munching on whey protein.

Whey protein – clearly a dairy product. Cow’s milk is made of two major proteins, and whey is one of them. Proteins, such as whey are made up of smaller sub-units known as amino-acids. Whey proteins contain a high level of an amino-acid known as leucine. Leucine (along with another few aminoacids in milk – isoleucine and valine – if you’re interested!) has been shown to promote insulin and IGF-1 release – which as mentioned before may be associated with acne development.

So this got my brain ticking. Do groups that consume large amounts of whey protein get acne? Body-builders sprung to mind. Surprisingly, there are next to no studies out there investigating this. I found a handful of case reports on Pubmed about milk protein abuse and acne onset and aggravation. Unfortunately, a handful of case reports don’t make a clinical trial so there isn’t much information out there.

But put simply, we are recognizing a link between acne and dairy, albeit a weak link. Whey is a major component of cow’s milk and found in many protein powders and health snacks. So should we be asking ourselves if over-indulging in these can contribute to the acne process? The honest answer is, I don’t know, but it literally is food for thought.

Personally, I think what I’ve learnt is that maybe going back to my original school of thought of everything in moderation wasn’t that wrong after all. I will limit my whey protein intake to see if it makes a difference. Anything that can potentially help my acne! Whilst I don’t think dermatologists should be treating acne with diet alone, I think the time for us to be closed-minded has gone, and it may prove to be a useful adjunct in the future in addition to the tried and tested acne therapies that we know work.

 

 

City living and your skin

I can’t have been the only person that was slightly alarmed at the Time Out London story from last week (http://www.timeout.com/london/blog/the-big-smoke-londons-pollution-levels-are-already-above-the-annual-limit-010816). Eight days into 2016 and London’s pollution levels are already above the annual limit. For those of us city dwellers, this is definitely not good news for our skin.

 As skin is your outermost barrier, it is one of the first and largest targets for air pollution. So, what exactly is air pollution? Air pollutants include the polycyclic aromatic hydrocarbons (PAH), volatile organic compounds (VOC), oxides, particulate matter, ozone, and cigarette smoke. Prolonged and repetitive exposure to these agents can have negative effects on the skin.

 Scientific studies in both animals and humans have shown that these components of air pollution can contribute to premature skin ageing (wrinkling, pigmentation spots) and worsening of inflammatory skin diseases such as eczema, psoriasis and acne. One major mechanism is via the generation of reactive oxygen species that can damage DNA in skin cells.

 Short of leaving the city and moving into the countryside, what can you do to limit damage?

1. Cleanse your skin every night to remove dirt and environmental toxins from the skin surface

2. Exfoliate once weekly (less if you have dry or sensitive skin) to give your skin a deeper clean. This will also improve the penetration of any products that are later applied to the skin.

3. Use an antioxidant serum – antioxidants such as vitamin C and resveratrol have the ability to neutralize damage caused by reactive oxygen species.   They certainly have a role in your anti-ageing armory.

4. Use a regular sunscreen (SPF 15 or above) – don’t forget your skin also needs UV protection to help reduce risk of skin cancers and signs of premature ageing.

5. Moisturise daily, particularly if you have a tendency to dry, inflammatory skin conditions e.g. eczema and psoriasis. This will keep your skin hydrated helping to maintain the integrity of the barrier function of your skin.

For many of us women settled in city life, it is worth thinking about taking extra precautionary measures to protect against noxious chemicals we are exposed to on a daily basis. We may not be able to control the environmental factors that lead to skin inflammation and ageing, but it is in our hands to try and limit these.

Topical Retinoids: Are they all the same?

Any dermatologist worth their salt will advocate the use of topical retinoids to address anti-aging concerns. Since the first retinoids were developed in the early 1970s, they have become a firm favourite with both beauty editors and cosmetic dermatologists alike.

Topical retinoids are derivatives of vitamin A. They work by increasing skin cell turnover, boosting collagen production, and improving skin tone and pigmentation.

But are they all the same? Is one retinoid product just as good as the next? Are over the counter products similar to prescription strength ones?

Retinyl esters, retinol, retinaldehyde, adapalene, tretinoin, isotretinoin, and tazarotene are all different types of retinoid. The key, however, is that your skin is only able to use a retinoid in the form of retinoic acid.

All types of retinoid product applied to the skin are converted to retinoic acid. So a retinol-containing product is firstly converted into retinaldehyde and then retinoic acid i.e. a two-step process. Products that require the fewest conversion steps tend to be more effective for anti-aging purposes.

Retinyl esters, retinol, and retinaldehyde are available over the counter. Tretinoin (retinoic acid), isotretinoin (synthetic retinoic acid), and the newer retinoids, adapalene and tazarotene are prescription only.

Most of the initial scientific studies looking at skin aging and retinoids were carried out with tretinoin (retinoic acid). Tretinoin was found to be 20 times more potent than retinol. However, that said, 1% retinol has been shown to be effective at 12 weeks in improving fine lines and wrinkles.

If prescription strength tretinoin is more effective then why do we bother with the other agents? Well, this largely comes down to tolerability. The more potent the retinoid, the higher the likelihood that it will cause problems with skin irritation, such as burning, stinging, redness, and scaling. There is a trade-off between clinical benefit and potential side-effects.

I would recommend, however, that if you are looking for a suitable over the counter retinoid product, choose one that contains either retinol or retinaldehyde. These are likely to be more effective than the retinol derivatives such as retinyl acetate, retinyl propionate, and retinyl palmitate. There are many good non-prescription strength products available e.g. Skinceuticals retinol 1%, Avene retrinal 0.1%. If there remains any doubt, find a friendly dermatologist who will be able to run through the ideal product for your skin type and anti-aging concerns!

 

The problem with skin specialists

A quick search of Google shows how we are a nation obsessed with our skin, and rightly so, as it is after-all, the largest and most visible organ of our body. However, delving a bit deeper, there is a darker, borderline deceitful edge to clinics that claim to provide skin experts that will treat everything from the freckles on your hand to the wrinkles on your forehead.

What makes me say this, you ask? Well, firstly, it is the broad definition of the term “skin expert” or “skin specialist”.   There are no rules or regulations in the UK to control the use of these terms. One does not have to go to medical school, and for those that do, there is no requirement to finish specialist training to self-profess themselves as experts.

Dermatologists are the only doctors in this country that complete specialist training in skin health and disease. Following years of general medical training and completion of postgraduate exams, a selected few get onto competitive training schemes. Many years are spent learning about different facets of skin disease, skin surgery, and pathology. We are talking about highly trained doctors that can tell whether the freckle on your hand is just a freckle and not early signs of skin cancer.

So why would you do your skin a disservice and see anyone other than a dermatologist for your skin problem – cosmetic or otherwise? If I had an issue with my skin, I would want to see a dermatologist, just like if I had a problem with my heart, I would want to see a cardiologist. If that is my standard, why should I expect any different or any less for my patients or clients?

Patients attending private or high street clinics that offer skin expertise need to savvy up and learn to question those individuals offering them treatments. Patients have a right to know their practitioner’s credentials but very rarely do I see this right exercised. Everyday I find myself staring at images of clinics plastered over social media claiming to have the best skin experts. On closer inspection, it becomes apparent that there is no genuine specialist but a lot of PR and false advertising.

And why does it matter to me? Firstly, it is a probity issue. It is a privilege to treat people and I like to think that most people in caring professions are honest. It is not sufficient to leave medical training, do a day “learning skin” and then market yourself as an expert. We all know expertise comes from training and experience. Secondly, it is dangerous. I hear of patients coming to my NHS cancer clinic telling me they have had moles removed by laser for aesthetic reasons in private high street clinics without a dermatologist. How does the practitioner know they are not burning away a melanoma, the most serious type of skin cancer? People that treat skin must learn to work within their remits, and have an understanding of the potentially grave consequences of their mistakes.

So my advice is learn to question your doctor or specialist. Be satisfied that they are indeed qualified to treat what they say they are. A good starting point before agreeing to expensive treatments, particularly on the high street or in the private sector, is to check the General Medical Council Register. All doctors that have completed specialist training in the UK will appear on this. It is easily available online and all that is required is the name of the individual performing treatment. And the moral of the story? Beware of anyone doing anything to your skin without asking them if they are indeed qualified to do so.