Healthy skin contains a significant quantity of water that is kept in place by ‘magnets’ that attract and hold the water deep in the living layers. This ‘magnet’ is a carbohydrate substance called Hyaluronic Acid. In addition to the Hyaluronic Acid, there is a vital layer of lipid (oil) located on the outer surface of skin called the lipid bi-layer. The lipid bi-layer actively seals the water into the skin, preventing evaporation to the atmosphere.
Skin that is deficient in either Hyaluronic Acid or the lipid bi-layer will hold less water or lose excess water to the atmosphere resulting in dry, tight, sensitive, flaking skin.
Avoid combining: Vitamin C + Retinol
Vitamin C, is an ingredient with multiple mechanisms of action. Proven to be effective as an anti-oxidant, a dark spot lightener and a collagen rebuilder. As a powerful anti-oxidant, Vitamin C helps combat skin damage, caused by the sun and environmental pollution. Vitamin C also assists in lightening dark spots for a brighter more even complexion and builds collagen to reduce the look of fine lines.
Retinol is an analogue of Vitamin A, that can lighten brown spots and improve fine lines with consistent use. There is a chance that Retinol may make skin photosensitive.
Combining Vitamin C and Retinol should be avoided as these ingredients work at different pH levels. Vitamin C is formulated with a low pH of less than 3,5 while Retinol has a pH of between 5,5 – 6,3. The optimal regimen for these two ingredients it to apply Vitamin C in the morning along with sunscreen and Retinol at night.
Avoid combining: Vitamin C + Benzoyl Peroxide
Benzoyl Peroxide has the ability to oxidise Vitamin C, making Vitamin C less effective.
Combine with caution: Vitamin C + Alpha and Beta Hydroxy Acids
Both Vitamin C and Hydroxy Acids work in acidic environments so they could potentially be used together, however this combination could be more irritating for skin. A combination of Vitamin C and Salicylic Acid could work for those with oilier skin types.
Vitamin C and Niacinamide
Both ingredients are effective in the treatment of blemishes but they should always be used at different times of the day or week.
Avoid combining: Retinol + Benzoyl Peroxide
When Retinol products are combined with Benzoyl Peroxide products, their effects can cancel each other out. Avoid using potentially irritating products with Retinol such as a product containing an acid. Retinol should also be avoided after a chemical peel or resurfacing laser treatment.
Avoid combining: Retinol + Alpha and Beta Hydroxy Acids
Alpha and Beta Hydroxy Acids (AHA and BHA) are used to exfoliate the skin for optimal skin health. AHAs include Glycolic, Lactic and Citric Acid, while BHA generally refers to Salicylic Acid. When two active ingredients are used together, there is a chance that skin experiences excessive dryness, redness and irritation. To avoid this happening, it is best to use an exfoliating product and an active ingredient at different times of the day and or week. For example, if you plan to do a AHA or BHA treatment at night, do not use a Retinol the same night.
Avoid combining: Glycolic acid + salicylic acid
Glycolic and Salicylic Acid are exfoliators so using them together would cause an over exfoliation of your skin. It is best to use them separately only.
Avoid combining Peptides + Alpha Hydroxy Acids
Peptides are not recommended to be used simultaneously with AHA’s as the acidic pH is not an optimal environment for peptides to be effective.
Take note of application order: Lipid (Oil) based + water based
Oil and water do not mix therefore a water based serum is always applied to the skin first and then a lipid (oil) based serum can be applied.
Is it healthy to apply oils to my skin
Skin that flakes, feels tight, is sensitive or appears red is likely suffering from an impaired barrier. The surface of healthy skin contains an essential layer of specialised lipid (oil) called the Lipid bi-layer. When this layer is deficient or missing, excess water is allowed to escape through the skin to the atmosphere resulting in these symptoms and signs.
The use of lipid supporting oils can replace much of the missing bi-layer and thereby bring relief to the skin. It is important to note that not all oils provide the same degree of lipid bi-layer support. Squalane, ceramides, hemp seed oil, are all examples of non-comedogenic lipids (oils) that provide significant support to an impaired barrier and could be considered ideal relief to dry skin.