Skin science: The natural ageing process of the skin
The skin goes through a natural ageing process as we mature. The skin’s three - layer structure – the epidermis, dermis and subcutaneous tissues –makes up the top, middle and bottom layers of the skin respectively and each contributes to ageing. The dermis contains the proteins collagen (which strengthens the skin) and elastin (which makes skin elastic), while the subcutaneous tissues contain fatty deposits. Mature skin produces less sebum, resulting in a drier, more wrinkle-prone complexion. At the same time, lower levels of collagen and elastin result in thinner, saggy skin. The dermis, which supplies the epidermis with key nutrients for skin renewal and repair, delivers fewer nutrients to the top layer of the skin. In addition, the fatty deposits in the subcutaneous tissues get smaller as part of the ageing process and the skin becomes thinner. Each of these chemical changes in the skin’s layers result in dry and sagging skin with deep lines, wrinkles and possibly age spots.
Other factors play a part in the way our skin ages. We can thank (or blame) our lineage for the genes responsible for the natural and irreversible physiological ageing process, while photo-ageing is premature ageing caused by UV exposure. The International Dermal Institute says that up to 95 percent of premature ageing signs are the result of sun exposure, particularly freckles, age spots, spider veins, leathery skin, fine wrinkles, loose skin, a blotchy complexion, actinic keratoses and skin cancer. Diet, exercise, stress, pollution, smoking, harsh skin care products and improper cleansing techniques can play a part in speeding up the ageing process of the skin.
Skin Cell Renewal
Skin renewal slows as we age. Between the ages of 15 and 25 years, the skin renews itself completely every 20 days or so, but as we approach our thirties, this rate slows to around 28 days to complete a full cycle, resulting in a thicker, more dull skin. As the skin cell turnover slows, the sebaceous glands become less active, making the skin drier. This natural slowing of skin cell turnover can be sped up by incorporating a skin care regimen or specialised skin treatments designed to accelerate the skin renewal process by exfoliating dead, dull skin cells.
Types of Exfoliation
A chemical peel uses an acid solution to remove the damaged outer layers of the skin, revealing smoother textured skin beneath. There are three basic types of peels: superficial, medium and deep, each incorporating a type of acid. Glycolic or salicylic acids are best for oily skin and trichloroacetic acid (or TCA) is used in deep peels.
Superficial peels are used to improve the appearance of pigment changes in the skin, acne scars, mild sun damage, or fine wrinkles in all skin types. They can be done on the face and on other parts of the body. A superficial peel may also be used to prepare the skin for a deeper peel. Superficial peels are usually performed every week for up to six weeks until desired results are achieved. The procedure can be performed monthly thereafter to maintain desired results.
Medium peels are used to treat mild to moderate wrinkles, long-term sun damage, pigment changes, and precancerous lesions of the skin (usually caused by sun exposure). Medium peels are used most often on the face and can be performed every six months to a year to maintain desired results.
Deep peels are used to treat severe wrinkles, long-term sun damage, pronounced pigment changes, coarse skin texture and precancerous skin lesions known as actinic keratosis. Deep (phenol) peels produce dramatic results that may take several months to heal and therefore can only be done on the face. Deep peels are not done on darker skin types, because they bleach the skin. Because they work at such a strong intensity, reaching the deeper levels of the dermis, they are classed as surgery and should be a once-off skin treatment only.
Chemicals Peels cannot:
• Remove or reduce the appearance of blood vessels on the skin.
• Reduce pore diameter.
• Remove keloidal scars (A firm, rubbery or shiny scar which is the result of an overgrowth of granulation tissue (collagen type 3) at the site of a healed skin injury which is then slowly replaced by collagen type 1.)
What skin types are suited for
Chemical peels are not for everyone. While superficial peels can be effective on many skin types, deep peels in particular are best suited for those with fair skin and light hair as in some instances they can bleach the skin and affect the skin’s ability to tan. Patients are preferably in good physical health, preferably non-smokers and have realistic expectations of the outcome. Individuals with heart problems are not ideal candidates as phenol poses a risk for heart conditions. Chemical peels are not suitable for those who are taking Roaccutane or have taken it in the previous 18 months and they must not have active skin infections, including most kinds of acne as these can increase your chances of scarring.
Post-peel at home care
Proper care of the skin after a peel is very important in order to speed healing, help results last, prevent infection and prevent pigmentation from sun exposure. After a light or superficial peel, patients should be able to resume normal activities right away, although the skin may feel tight and be red for six to eight hours afterwards. More invasive procedures require more recovery time, depending on the strength of the chemical:
• Cleanse the skin frequently with water or a special face wash.
• Change the dressing or ointment on the wound (for medium and deep peels).
• Moisturise the skin daily.
• Avoid sun exposure until peeling has stopped and sunscreen can be used. New skin is susceptible to UV damage, so sunblock – preferably in conjunction with an antioxidant serum – must be used daily.
Chemical exfoliation for home use
The most commonly used chemical exfoliation ingredients used in home care are AHAs – alpha hydroxy acids. The most common AHAs in at-home skin care are glycolic acid (derived from sugar cane), lactic acid (derived from milk), citric acids (from oranges and lemons) or salicylic acid. Products containing AHAs are commonly used on the face and neck areas to exfoliate sun-damaged and dry complexions while also improving moisture content in the skin. According to the University of Maryland Medical Center, AHAs decrease the amount of skin cells that are shed and may increase collagen and skin elasticity. Alpha hydroxy acids are reported to improve wrinkling, roughness, and mottled pigmentation of photo damaged skin after months of daily application. They work best in a concentration of five to eight percent and at a pH of three to four and cause the cells of the epidermis to become “unglued” allowing the dead skin cells to slough off, making room for regrowth of new skin.
Other potential benefits of AHA usage:
• Increase cell renewal factor (CPF) for improved natural exfoliation
• Reduce acne and sebum production
• Improve the skin’s natural barrier function
• Minimise enlarged pores
• Diminish fine lines, superficial wrinkles and lip creases
• Increase intercellular lipids
• Reduce surface skin buildup and thickness by exfoliating dead skin cells
• Allow active ingredients to be more readily accepted by the skin
• Fade discoloration due to sun damage, hormones and scarring
• Soften rough, thick skin for improved skin texture and overall appearance
• Help to rehydrate skin by activating hyaluronic acid production for improved moisture binding properties and better hydration
• Increase collagen and elastin production for enhanced dermal thickness
• Help dissolve and minimise stretch marks and other skin lesions
Who is suited for AHA usage?
Unfortunately, while appearing in the product lines of most anti-ageing skin care ranges, not every skin type is suited to AHA usage. The best candidates for AHA usage are those who have relatively mild skin imperfections and conditions and who want to rejuvenate their skin without the recovery time of harsher treatments. Patients whose skin starts to develop early signs of photo-damage such as freckles, sun spots and actinic keratoses as well as melasma, fine lines and mild acne. AHAs may cause adverse effects of AHA such as itching, skin irritation, blisters and chemical burns on people with sensitive skin. AHAs should not be used too often at high concentrations because they can leave the skin quite dry and in some cases irritated. Sun sensitivity is another major side effect and AHA products can increase sun sensitivity by as much as 50 percent, so a high SPF sun block must always be recommended to clients after an AHA treatment and in conjunction with products containing AHAs.
Microdermabrasion is a hugely popular cosmetic technique which uses fine abrasive crystals and vacuum suction to painlessly remove the stratum corneum. The treatment is used to assist in the appearance of common skin problems ranging from superficial acne scars to uneven pigmentation as well as melasma and hyperpigmentation. Microdermabrasion is particularly beneficial when used in conjunction with facial laser treatments as it helps turn over the dead skin cells from the laser treatment, increasing its results.
Other potential benefits of microdermabrasion:
• Refreshingskin texture
• Helping to treat certain types of acne and clean blocked pores.
• A series of four to five treatments may improve the appearance of melasma
• After some lasers to speed shedding of brown pigment.
• Reduce the appearance of sun damaged skin.
• Reduce the appearance of fine lines
• Improve clogged pores.
• Reduce breakouts.
• Improve uneven skin tone, texture and elasticity.
• Reduce the depth of raised and pigment scars.
Who is suited for microdermabrasion?
People who have thick, oily skin types with acne, discolorations, superficial lines and wrinkles, uneven texture or sun-damaged skin are good candidates for Microdermabrasion.If the client has no history of hypo/hyper-pigmentation or keloid scarring in their family, a series of microdermabrasion could be considered an alternative to a deeper invasive peel. However, microdermabrasion is not suitable for deeper wrinkles and scars, deep hyperpigmentation problems (areas of darker pigment) or for those with broken capillaries as they can exacerbate them. Microdermabrasion risks are highest for patients with sensitive skin or a history of inflammation such as rosacea or psoriasis, so a consultation prior to treatment is important. A client should be prompted to reveal if they have any undiagnosed lesions, recent herpes outbreaks, warts, stage three or four acne or active rosacea (which can be worsened), unstable diabetes (due to poor wound healing abilities) or auto-immune disorders as they are at higher risk of developing infections.
Home skin care after microdermabrasion
Because fresh skin has been exposed, clients must be advised to apply sunblock daily and to avoid direct sunlight and tanning booths. They should also avoid products containing harsh chemicals, dyes, or perfumes until the skin has fully healed. Microdermabrasion can be done as frequently as weekly or up to every eight weeks depending on the individual’s skin tolerance. Many people choose to start with weekly treatments for three sessions to obtain results, then change to a monthly regimen to maintain them.
To exfoliate or not to exfoliate?
With multiple advances in both at-home and in-spa exfoliation it’s no wonder that clients are considering it an essential part of their skin care regimen. But is it really suitable for all skin types and is it possible that people are doing more harm than good with their ‘fresh’ skin addiction?
The Argument for Exfoliation
As skin dryness and dullness appears around age 35, many therapists believe this to be a viable time to begin treating the skin with microdermabrasion, skin peels and at-home exfoliation products containing alpha hydroxy or beta hydroxy acids. Exfoliation is often touted as offering the below benefits:
• Reducing acne and blackheads.
Acne-prone skin sheds more skin cells than other skin types, but instead of falling away, the dead skin cells stick to the skin, which can clog pores and hair follicles, leading to blackheads and blemishes. In theory, regular exfoliation will speed the process of skin cell turnover rendering clogged pores less likely to occur.
• Increasing product absorption
Dead skin cells sitting on the skin’s surface can become a physical barrier to the active ingredients of skin care products. By exfoliating dry, dead skin cells before product application, the likelihood of absorption into the epidermis is increased.
• Reducing the thick layer of damaged skin cells.
Sun damaged skin thickens with age, resulting in dull, wrinkled skin. Sloughing away these thick layers of damaged cells can make the skin appear brighter, softer and younger.
• Reducing dry patches.
As we age, the natural process of skin cell renewal becomes unstable, resulting in dry patches. Regular exfoliation can help to reduce these patches resulting in a more even complexion.
The argument against exfoliation
Dr Catherine Stone of The Face Place believes exfoliation shouldn’t be self -diagnosed by the client as it is not a one-size-fits-all technique. “It’s important for clients to build a good relationship with a trusted dermal therapist, because when they take things into their hands there can occasionally be too much of a good thing.” She advocates the use of microdermabrasion only for those with thick, sebaceous skin types and only every six to eight weeks, while glycolic and lactic products and gentle peels are better suited to finer skin types. She is wary of deep peels. “Deep peels are very damaging – they can create scar tissue, cause inflammation and the deeper peels run the risk of infection,” she says. “Furthermore, because scar tissue has fewer skin cells, repeated deep peels can result in finer skin.” Catherine suggests educating clients on other skin treatment modalities such as microdermaplaning (which gently removes the dead skin cells on the surface of the skin as well as the ‘peach fuzz’), dermal rolling and PRP (Platelet Rich Plasma Therapy).
Contrary to the popular theory that the dead skin cells dull the skin, block pores and prevents skin from breathing, Dr Des Fernandes, founder of Environ skin care believes the surrounding lipid bi-layers of these “dead” cells are there to protect the skin. By exposing the younger cells, he suggests more water is lost through the skin and these cells cannot rapidly adapt to this new, harsh environment and after a few days the skin feels dry and the surface lacks lustre.
Dr Fernandes is not the only doctor who thinks exfoliation may be damaging the skin. Osmosis Skin Care founder Dr Ben Johnson’s theory is that because the dermal blood supply (which also feeds the epidermis) struggles to keep up with the nutritional workload in older skin, this declining blood supply forces the skin’s cell turnover rate to slow in response to the lack of nutritional/immune support. He believes exfoliation begins a vicious cycle, by damaging the epidermis and forcing the dermis to divert scarce resources to fix the barrier as soon as possible. He feels the nutritional/antioxidant deficiencies that caused the thinning of the skin in the first place are worsened by placing further demands on the skin due to epidermal damage.
In an article entitled, ‘The Epidemic of Exfoliation,’ Florence Barrett-Hill concedes that peeling is useful as a tool to enhance the penetration of the vitamin and coenzyme actives required to make changes to the skin cell, in order to reduce lines and pigmentation. But, she says a therapist should attempt to analyse why the skin accumulated the dead skin cells in the first place before embarking on a treatment programme. Barrett-Hill’s concern is the overuse of professional peels and accompanying modalities for peeling and the belief that continual peeling or abrading the skin will be the answer to wrinkles, pigmentation and acne. She raises another valid point, that in many instances therapists do not offer skin support or treatment after the peeling programme, which demonstrates no concern for the inflammatory response caused or the appropriate healing required completing the treatment. “We should not over-exfoliate because over-exfoliation leads to large pores, whiteheads, pimples and skin dryness. Mechanical peels can have destructive consequences and lead to skin irritation and damage. Excess scrubbing is proved to cause irritation and inflammation and [speed up] derma ageing,” she says.
The type of mechanical facial scrubs used is another consideration; many of which contain components such as milled walnut shells, blended sea shells or even small particles of plastic. After examining the skin of experiment participants, the Study of American Association of Dermatology discovered that the derma surface appeared to possess scratches and be irritated and inflamed. For this reason, many therapists feel the preferred method of exfoliation should be chemical and contain hydroxy acids such as glycolic acid, salicylic acid or lactic acid. When used correctly, these acids penetrate into the follicle to remove dead cells rather than sloughing dead cells off the surface. A word of caution would be wise when discussing chemical exfoliants with clients as over exfoliation is likely the result of a combination of home-use cleansers, washes and scrubs – each with their own exfoliation properties.
Tailored treatments the best – and safest bet
As with any skin treatment, exfoliation should never be a ‘one size fits all’ solution. Different exfoliation techniques work best with certain skin types, so a custom skin analysis to decipher the skin type is an essential prerequisite. Whether exfoliation is harmful or not is best decided with a careful interpretation of the skin type, in conjunction with the client’s needs and expectations. Before proceeding with a treatment, find out what products the client is use and ensure that the client understands the importance of a formal home care and follow up regimen in order to maintain results and assist the healing processes of the skin.