On the market, there are so many different cosmetic products with anti-aging properties. They protect our skin from UV-radiation and harmful influence of free radicals. After 25 year of life, each of us looses 1% of collagen in the skin each year. Therefor many cosmetics include ingredients, which stimulate fibroblasts to produce structural proteins like (collagen and elastin). For sure you have in your bathroom many different cosmetics which suppose to keep you away from occurrence of wrinkles. Different creams and serums make your shelves full. But do you really know which active substances you can combine with each other and which you shouldn't? Actually there are indeed some cosmetics which shouldn't be used together. Some combinations can be harmful, some of the active substances combined together will simply loose their properties. In this entry I would like to have a closer look on different cosmetic ingredients and show you how you can use it without harming your skin and achieve the best effects of your daily skin care routine.

Let's start with cosmetic ingredients that do not really fit together.

RETINOL / ALPHA-HYDROXY ACIDS (AHA)
RETINOL / VITAMIN C (L-ASCORBIC ACID)
Retinol (vitamin A) is very popular anti-aging agent. It stimulates collagen and elastin biosynthesis, angiogenesis (building of new blood vessels), inhibits action of degrading collagen metalloproteinases in the skin and regulates epidermal renewal processes. Pretty similar way of action have alpha-hydroxy acids (mandelic acid and glycolic acid): they can act as anti-aging agents by stimulating fibroblasts to collagen and elastin production as well, moisturize the skin and exfoliate.Vitamin C has similar properties. It stimulates collagen and elastin production and acts as a strong antioxidant. Additionally it can inhibit tyrosinase enzyme and therefor reduce melanin production. Retinol is known to be a pretty irritating agent which is not really good for sensitive type of the skin. Together with L-ascorbic acid it can cause very strong irritations of the skin. Similarly will work combining it with AHA and actually with BHA (salycilic acid) as well. A good thing to do would be treatment with AHA for some time, short brake and slow introduction of cosmetics with retinol / retinoids afterwards. Moreover retinol is assumed to be a pro-oxidant as well, which could potentially oxidise vitamin C and make it inactive. But, is there a way to combine two of them in a daily care routine? Yes! You could easily use products with vitamin C in the morning and the ones with retinol in the evening. What's more, there are many L-ascorbic acid derivatives (magnesium ascorbate, glucosyl ascorbic acid or ethylated ascorbic acid- see the post about vitamin C), which don't irritate the skin and are suitable to be used by people with very sensitive skin types. About anti-aging treatment with retinoids I have written a post some time ago 🙂

VITAMIN C (L-ASCORBIC ACID) / AHA
Combining both of them, similarly to retinol and AHA combination, can lead to strong irritation of the skin. People using cosmetic products with alpha-hydroxy acids should resign from therapy with vitamin C. However, it is possible to combine AHA with vitamin C derivatives.

NIACYNAMID (VITAMIN B3) / VITAMIN C (L-ASCORBIC ACID) OR AHA
Vitamin B3 has similar way of action to many anti-aging compounds  (for example vitamin A). It reduces TEWL (transepidermal water loss), regulates regeneration processes in the skin, stimulates production of collagen and elastin in fibroblasts. Similarly to vitamins C, A and E it is a strong antioxidant. It reduces hyperpigmentation and prevents skin from the formation of new pigmentation defects. Due to it's anti-inflammatory properties, it is very useful in treatment of acne and in daily care routine of oily skin type- it has been shown to reduce production of sebum and tightens enlarged pores. Niacynamid is known to have it's function in pH 6 – 7. Vitamin C and AHA products have acidic pH (much lower then then 5). If we will combine these active substances, vitamin B3 will simply not work. Of course a good idea would be to use niacynamid in the morning and products with vitamin C or hydroxy acids in the evening.

VITAMIN C (L-ASCORBIC ACID) / COPPER PEPTIDES
These are both wonderful anti-aging substances. Copper peptides (Cu-palmitoyl hexapeptide-14) stimulate fibroblasts to produce structural proteins. They reduce activity of collagen degrading metalloproteinases and enhance skin thickness. However, copper easily can oxidize L-ascorbic acid, which actually will loose it's activity. Moreover, vitamin C with copper can act as pro-oxidant.

Which substances are good to combine? Actually, there are some cosmetic ingredient, which we suppose to use together!

RETINOL / NIACYNAMID (VITAMIN B3)
Niacynamid has strong anti-inflammatory properties and can reduce irritation caused by retinol. Moreover, due to its anti-aging and antioxidative properties it can make therapy with retinoids much more successful.

VITAMIN C AND IT'S DERIVATIVES / FERULIC ACID
These are both very strong antioxidants. They have amazing anti-aging properties. Both reduce harmful impact of UV-radiation. Ferulic acid, similarly to vitamin C in a form of L-ascorbic acid has very low pH. Both feet together very well and are often used as chemical peels and as ingredients of different creams and serums. I would advise to use it during summer additionally to UV protection. Cosmetics with ferulic acid will be perfect to be used in the morning skin care routine, vitamin C and it's derivatives in the evening.

All of these active substances can be combined with moisturizing products. Perfect combination will be vitamin C and it's derivatives and ferulic acid with low molecular weight hyaluronic acid and panthenol. First two substances will protect your skin from UV light and stimulate fibroblasts to produce structural proteins, the last two will perfectly moisturize the skin and reduce irritations. Every active substance can be combined with liposomal collagen peptides as well. Actually, this is the only form of collagen, which has anti-aging properties. About collagen I have written an entry some time ago 🙂 It has very big molecule and can not be absorbed by the skin. Application of collagen rich products on the skin, will make it to cover the skin with very thin layer. As a result, water loss through epidermis will be reduced and skin will stay only much more hydrated. Peptides (small parts of protein) of collagen encapsulated in liposomal vesicles can easily reach fibroblasts and stimulate them to produce it's native form.

Arkadiusz