Sun is a frenemy (friend & enemy) for the skin. Especially the spring sun feels good, is warm, you get a nice tan. On the other hand, it damages your skin, causing premature skin aging and even skin cancer in the long run. An alternative to get a nice tan is to use a self-tanner. But what exactly is that?
The active self-tanner ingredient is DHA
One of the best known agents is dihydroxyacetone (DHA). DHA is a sugar form that has been used in the cosmetic industry for over 50 years. It can be obtained from natural sources such as beets and sugar cane as well as synthetically. It is very popular because the tan obtained with it is very similar to that achieved by sunlight or tanning beds.
DHA reacts with certain amino acids (including glycine, lysine and histidine) in the upper layers of the epidermis. A reaction then occurs between DHA sugar and amino acids in the skin, called a Maillard reaction. This forms a brown-colored substance called ‘melanoidins’ and knows how to attach to the upper layers of the skin. The maximum tan is reached after 4 to 6 hours. The color starts to fade again after about 4 days.
DHA is a relatively harmless substance, but it can cause unintended effects.
Only a few cases of contact allergy have been described in the literature. It is quite rare.
2. Increased production of free radicals.
Animal experimental research showed that the Maillard reaction generates free radicals. These are highly reactive molecules that damages cell structures and also collagen and elastin fibers in the dermis.
If you go out into the sun after applying a self-tanner, UV rays can make DHA more unstable. This study concluded that DHA treated skin generated 180% more free radicals during sun exposure compared to untreated skin.
The free radicals released by DHA-induced oxidative stress can cause premature skin aging. Think of more fine lines, wrinkles, hyperpigmentation and longer-term skin cancer. Also, DHA has been linked to DNA damage, leading some researchers to question its long-term safety. The study conclusion is based on in vitro cell cultures, there are no randomized studies.
3. False sense of security
The brown color obtained by DHA provides no protection against ultraviolet rays from the sun, only an SPF value of 1-3. There is a good chance that you will burn your skin due to UV-B radiation. For this you will have to use extra sun protection.
4. Less vitamin D-production
Regular use of self-tanner can reduce your body’s production of skin’s own vitamin D. This study showed that topical 9% DHA formed melanoidin pigments inhibit vitamin D production in the skin.
In 2022, the guideline for self-tanners in Europe will be tightened. Self-tanning products in the EU are now limited to a maximum of 10% DHA. The regulation also sets a 6.5% limit for use in non-oxidative hair dyes.
A DHA alternative, is that better?
There are new DHA free products on the market. One of them is erythrulose, obtained from red raspberries. It is a non-toxic cosmetic self-tanner. However, it works the same as DHA.
When erythrulose is applied on its own, it takes longer to get a tan and it fades faster. The color produced is more red than brown.
In combination with DHA, the color is said to last longer and provide a better tint. Erythrulose also has an increased production of free radicals, similar to the effect seen with DHA.
Tips and tricks
First of all, an occasional self-tanner isn’t a problem, but a frequent user might appreciate these tricks. How do you get the most out of it without too much skin damage?
To get more out of your self-tanner, exfoliate your skin beforehand. This gives a better and more even color without too many uneven spots.
Apply a self-tanner in the evening, instead of during the day. A study showed that DHA induces free radical formation and lasts several hours. In the evening you will not be bothered by the sun and DHA can do its job.
Use a sunscreen during the day, better is a mineral sunscreen. This works immediately after application and has a wide UV coverage.
Skin care with antioxidants such as vitamin C, E, nicotinamide, coenzym Q10, astaxanthin, green tea. In particular, the combination of vitamins C, E and ferulic acid reinforce each other and have up to 8 x more anti-oxidant effect. More about anti-aging cream
While you are here
Melanocytes also called pigment-producing cells. These cells are located in the lower layer of your epidermis, hairs and also in the iris of your eyes. Per square millimeter, between 1000 and 2000 melanocytes are found in the skin. That is about 5% to 10% of the cells in the basal layer of the epidermis. Although their size varies, melanocytes are typically 7 ɥm long and, like squid tentacles, interact with keratinocytes (skin cells). A melanocyte is roughly ‘connected’ to 40 keratinocytes. More about pigmentcells