I felt this was a very important post to write – the massive range of products containing various acids can make this area confusing and intimidating.  Before I used them myself, I was worried that my Irish skin would react and I’d wake up with a layer of skin on my pillow!  I’ve since been converted to the huge benefits of acid-based products and will be talking about them A LOT in my blog.  They form a central part of a skin care routine that reduces fine lines and the signs of ageing.  Many of them naturally occur in our bodies but lessen as time goes on so it’s important to supplement them in the right way to keep the skin as youthful as possible.  The beauty industry has seen many brands include acids in their products over the last decade which is testament to just how effective they can be – if used correctly.

They are not a product you should be afraid of, just ensure you choose the right one for you.  Below I’ve summarised the info on the main acids in a few lines – I hope this helps to explain what uses they have.  If you’ve any queries, then please do contact me directly and I’d be happy to help where I can.

Maria x


These can be naturally occurring or synthetic and are well known for their ability to exfoliate the skin, stimulate and increase collagen and aid in the reduction of wrinkles.  The most common AHA’s include Glycolic (from sugar cane), Lactic Acid (from sour milk), Malic Acid (from apples), Citric Acid (from citrus fruits) and Tartaric Acid (from grape wine).  They are effective in softening lines and improving the overall look and feel of the skin.  Dermatologists use them in higher doses than over the counter products in chemical peels.  Continuous use has been proven to be most successful without detectable inflammation, when monitored by skin biopsies.


Best known as Salicylic acid.  Mainly works as an exfoliant but can also act as an anti-inflammatory, anti-dandruff agent, antiseptic, hair conditioning agent, skin conditioning agent and preservative.  Basically, causes the cells of the epidermis (upper layer of skin) to shed more easily making room for new cell growth.  As a result, this invaluable ingredient has become very important to the skin care industry due to its multi-functional and versatile nature.  It can also help with hyper-pigmentation and in higher concentrations, can remove warts!  It effectively removes debris (also great for breakouts, blackheads & whiteheads) so the good stuff can sink in.


Retinoic acid or Tretinoin is the acid form of vitamin A.  It is a prescription drug which is very effective in treating acne and ageing skin.  With all acidic formulas used on the skin, you need to do your homework before getting a prescription or using it in your skin routine, especially this.  Retinoic acid is easily absorbed by the skin cells and helps regulate cell production to prevent the onset of wrinkles, dark spots and other signs of ageing. It increases cell turnover, killing old ones in order to boost new cell growth.  It also stimulates collagen production and thickens deeper layers of the skin, which is the source of wrinkles.  Although retinol is also a source of vitamin A, it has to be converted into retinoic acid before it can be absorbed by the skin. This makes creams containing retinoic acid more potent than those with retinol as the primary ingredient. Care should be taken though – retinoic acid can be extremely irritating and drying on the skin – they should only be used in prescription monitored amounts for short periods of time.


Retinol is a form of vitamin A that occurs naturally in the skin. It is commonly used in over-the-counter skin care products, normally in concentrations of around 0.05 to 2 percent. When retinol is topically applied to the skin, enzymes work to convert it into retinoic acid, which is clinically proven to improve lines, discoloration issues, and revitalize the skin.  Retinol is available in many high quality over-the-counter skin care products and due to lots of research into its efficacy, it has fast become one of the best ways to fight the signs of ageing.

The process of converting retinol into retinoic acid can take several weeks. In fact, it could take up to 3 to 6 months of daily use to provide a noticeable difference.  Therefore, you need to be in it for the long term, but it’s worth it.  You will also find it in darker, smaller bottles as it’s sensitive to sun and air, that’s why it’s recommended as a night time product and why it’s important to store it properly to get the best from it.


This is a plant-based, phenolic antioxidant that is found in bran, among other plants. Research has shown that it provides antioxidant benefits to skin while enhancing the stability of topical applications of antioxidant vitamins C and E. It also helps defend skin against environmental assault.  It slows the ageing process by reducing the effects of damaging free radicals on the skin as well as assisting in skins regeneration functions to tackle overexposed skin.


Derived from sugar cane, glycolic acid is the smallest AHA and has the best capability to penetrate the skin. This makes it’s very effective when it comes to stimulating collagen production and improving the skin’s appearance and texture.  In high concentrations, it is used in chemical peels, however it can make you sun-sensitive so it’s worth investing in a high factor to use alongside. Glycolic reacts with the upper layer of the epidermis weakening the lipids that hold dead skin cells together.  This allows for better exfoliation by exposing live skin cells.


This is one of the more popular acids due to its ability to exfoliate, reduce acne breakouts and some signs of ageing.  Originally derived from sour milk but more recently synthetically made, lactic acid is more gentle than glycolic, however over time can increase sensitivity to the sun.  It’s very powerful but best used sporadically rather than daily to help reduce wrinkles.  Can also be hydrating, while lightening and brightening those with skin discolouration.


Also known as BHA, this ingredient helps address the systemic causes of acne.  It helps shed dead skin in a similar way to how skin acts when we are younger.  It can break up the cells, which stick tighter in the inner lining of the skin pore, therefore unblocking blackheads and whiteheads.  Has also been used in products to treat warts, psoriasis and dandruff.


Ingredients such as gluconolactone and lactobionic acid are types of polyhydroxy acid (PHA). Made up of larger molecules than traditional AHAs, PHAs are typically gentler on the skin, causing less irritation. Unlike some AHAs, which can dry out the skin, PHAs are ideal for sensitive, dehydrated and dry skin types.  They work by promoting cell turnover to reveal healthier, smoother new cells.  Gluconolactone protects the skin from harmful UV exposure making it a great anti-oxidant.  For this reason, it is used in products that increase skin barrier function, improve skin brightness and reduce flare-ups associated with some types of acne, rosacea, dermatitis, psoriasis and melasma.


Derived from bitter almonds and is fat soluble, so good for oilier skin types.  It takes longer to penetrate the skin, so can be a good acid for those who are sensitive.  It basically dissolves the tiny bonds that hold skin cells together that lead to dull complexions.  It can also soften the appearance of fine lines and improve skin texture.


Used at times to keep the acidity of skincare products at the proper pH for shelf stability.  It can also help with skin cell turnover.  If it’s not on the ingredient list it’s probably just there as a preservative.  If, however it is on the ingredients list, it can act like a natural exfoliant without the scrubbing.


This ingredient is an acid, but as it’s natural, it’s slightly gentler on the skin than for example lactic or glycolic acid. Those with sensitive or very mature skin might prefer gluconolocatone as it is known to be milder.  It can serve as either an active ingredient (an ingredient that is included in a formula to provide benefits for the skin) or as an additive (an ingredient that is included to help improve the overall quality of the product). As an active ingredient, gluconolactone is often added to formulas because of its skin-conditioning properties, which reduce skin sagging and help maintain skin elasticity.  Suitable for sensitive skin, this is a great all-rounder.


This is a great antioxidant which helps reverse the signs of ageing along with retexturising the skin.  It attracts and retains moisture, so has skin plumping action too.  In addition, it can be a gentle exfoliator so can even skin tones and reduce the appearance of pigmented areas caused by exposure to UV rays.


Many studies support the notion that this acid exerts anti-ageing effects on the skin. Depending on the dose, it can inhibit collagen degradation along with protecting from hyperpigmentation caused by sun exposure.