Ask any dermatologist, myself included, and they will hands down tell you that cleansing is the most important step in your skincare routine, removing makeup, dirt and bacteria from the previous 12 hours. Coming in a close second (and a far more interesting process to me) is the next step in your regiment - exfoliation.

The Acid Index Lab

Either physical or chemical in nature, exfoliation removes dead skin cells from the top layer of the epidermis. This in turn produces a fresh, more radiant complexion while reducing discolouration, congestion, pigmentation, fine lines and wrinkles. It also improves the skin's absorption of the products - essences, serums, moisturisers and SPF (necessary in summer when dealing with acids) - that follow.


  • Step 1 - Cleanser
  • Step 2 - Toner
  • Step 3 - Exfoliant
  • Step 4 - Specific treatment
    eg acne / lightening
  • Step 5 - Serum
  • Step 6 - Moisturiser with SPF


Physical (otherwise known as mechanical) exfoliants are normally abrasive; scrubs, polishes - basically anything with a grain. Ingredients like walnuts, fruit pits and micro beads should be avoided as they can cause micro-tears in the skin due to the corrugated, sharp edges of the granules. Instead I would suggest you opt for a softer oatmeal, rice or sugar based scrub that lack irritants, gently sloughs off skin cells and nourishes with additional essential oils.


Chemical exfoliants come in a much wider variety and for women’s skin (which is up to 30% thinner than men’s skin ) I would more heavily recommend these oppose to mechanical exfoliants.

AHA’s (Alpha Hydroxide Acids) are derived from natural substances - sugars, nuts, fruit etc. These water-soluble acids have a small molecular structure, allowing them to reduce cell adhesion in the upper layers of the skin - think resurfacing and rejuvenation. BHA’s (Beta Hydroxy Acids) are oil soluble and possess a denser molecular structure, making them the perfect little warriors for a deeper, more thorough clean.

Still not sure what acids for you? Let’s break it down further and determine your diagnosis:

Lactic acid (AHA)

Made from* - Milk

Best For - Dehydrated skin, aging skin & pigmentation

Advantages - Considered a gentler exfoliant to glycolic acid, lactic acid also increases moisture levels and barrier function

Citric acid (AHA)

Made from* - Oranges & Lemons

Best For - Dull skin, sun-damaged skin, skin with unbalanced pH levels

Advantages - Brightening, regenerating and reparative

Tartaric acid (AHA)

Made from* - Grapes

Best For - Textured skin & tired skin

Advantages - An antioxidant, it stimulates collagen production & provides a gentle resurfacing

Malic acid (AHA)

Made from* - Apples & Pears

Best For - Acne-prone skin, dry skin

Advantages - Anti-bacterial & hydrating, it increases tissue respiration

Salicylic acid (BHA)

Made from* - The extract of willow bark

Best For - Mild acne, congested and oily skin, rosacea, enlarged pores

Advantages - Anti-bacterial and anti-inflammatory, it combats and reduces production of sebum

Hyaluroniclic acid

Made from* - Naturally occurring in the human body, synthetically reproduced

Best For - Dehydrated skin & dry skin

Advantages - Able to hold up to 1000x its own weight in water, it attracts water to create a moisture barrier in the skin.

Retinol acid

Made from* - Vitamin A, synthetically reproduced

Best For - Aging skin, stressed skin, acne-prone skin, dehydrated skin

Advantages - A strong exfoliant that increases natural production of hyaluronic acid and renews problematic skin at a deeper level than most AHA's.

Now there is one major acid I have left out from the above guide – glycolic acid. The most common AHA, it possesses the smallest molecular structure, allowing it to penetrate deep within the skin at a rapid rate. Glycolic acid treatments are virtually downtime-free, which come with mild redness or irritation as the only likely after-effect. Glycolic acid chemical peels are ideal for people who suffer from excess sebum and textured skin.

Myself and 111 Harley St. are strong advocates of glycolic acid, but only under the expert guidance of our aestheticians. Over the years I have witnessed an increase in the use of at home glycolic formulations - without the right guidance, this ingredient can have detrimental effects on the skin. Over time the resurfacing properties can thin the depth of the skin, over accelerating skin turnover and eventually increasing the development of fine lines, sagging and inflammation.

The alternative if you can’t make it to 111 Harley St. but crave the results a professional glycolic peel promises? I’ve developed an anti-ageing formula that delivers the same results as glycolic acid without the risking any overexposure – the 111SKIN CO2 Crystallising Energy Mask. The mask infuses the skin with carbonic acid, subsequently spiking oxygen levels to brighten the complexion and stimulate collagen for a more firm, youthful appearance. It’s basically a gentle peel you can do at home without compromising the integrity of your skin in the way that other glycolic based products do.

Still not sure what acid is right for you? Then either book in to see me or come down to your nearest 111SKIN counter and get diagnosed by our experts – your skin will thank you for it.

*Most acids are now synthetically derived to maintain stability, strength and remove allergens.