Natural sun protection
We are in the time of year when ultraviolet (UV) rays are at their maximum. These rays give us a good dose of vitamin D and are therapeutic for those who take a sunbath of at least 10 minutes without any sun protection.
The sunny days are more and more numerous. The holidays are approaching and you will undoubtedly want to take the opportunity to be tanned or spend long hours outside. Here is some information on UV rays, FPS and ingredients to use to protect your skin.
The 3 types of ultraviolet rays
According to Health Canada:
«Ultraviolet radiation is an invisible radiation which emits a wavelength between 100 to 400 nanometers (NM). A nanometer represents a billionth of meters. Depending on its wavelength, it can cross the ozone layer and have different health effects. The shorter its wavelength, the more harmful it is; However, it then penetrates the skin less easily.
- UVAs have a long wavelength (320 to 400 Nm). They enter the dermis and are responsible for immediate tanning, premature aging of the skin and can play a role in the appearance of certain cancers of the skin. They represent 95% of the UV rays that go to the surface of the earth.
- UVBs have an average wavelength (280 to 320 Nm). They enter the epidermis. They are responsible for long -term tan and sunburn, as well as most skin cancers. They represent 5% of UV rays that go to the surface of the earth. It is above all these rays that we are trying to block.
- UVCs have a short wavelength (100 to 280 Nm) and are the UV rays that have the most energy. They are very dangerous for all forms of life (even at very low dose). On the other hand, they do not cross the ozone layer and never reach the earth. » 1
1 https://www.canada.ca/fr/sante-canada/services/securite-et-risque-pour-sante/radiation/categories-sources/ultraviolet.html
6 health tips to take advantage of summer safely
When the UV index is 3 or more, you have to start protecting our skin.
- You have to cover yourself. Wearing sunglasses that have UV protection, a hat and if necessary long clothes. Favor pale colors and natural fabrics.
- Reduce exposure to the sun direct. Favor outdoor activities before 11 a.m. and after 3 p.m.
- Put sunscreen every 2 hours And after swimming, even if your sunscreen is "water proof" and the sky is cloudy.
- To drink a lot of water ! To avoid dehydration, it is important to drink before you thirst. Always bring a reusable bottle of water. Put a few mint leaves, lemon or hibiscus powder to refresh yourself more.
- Children imitate us ! Good habits will be acquired.
- Attention ! It is advisable to protect yourself even in cloudy weather or under certain conditions where UV rays are reflected On water, sand or concrete.
To know…
- Self -tanning products do not protect against UV rays. You have to use a sunscreen and protect yourself (shade, clothes, hat).
- Our skin is naturally colored by melanin and when it is exposed to the sun, it oxidizes. This is what creates tanning.
- Certain drugs can be sensitizing photo (the skin is then more sensitive to UV rays). Check with your pharmacist.
- Tanning devices damage the skin and should be avoided completely.
The difference between physical and chemical solar filters
There are two types of solar filters: chemical filters (synthetic products) and physical filters.
Chemical sunscreens are made with active molecules that come from organic source for the most part. These penetrate the skin to ensure protection against UV rays by absorbing them. These synthetic molecules (synthesized in the laboratory) can be less safe for a skin with acne tendency2 And for the skin in general. Some of these molecules are harmful to marine circles and potentially carcinogenic for us (see the list below). Studies are lacking to correlate skin cancer and these chemical molecules. If in doubt, it is best to abstain.
If you use sunscreen with a chemical screen, it will be important to apply it at least 15 minutes before sun exposure to give it time to penetrate the skin.
Physical sun creams are made with ingredients of mineral sources such as zinc oxide and titanium dioxide. To protect the skin from the sun, physical screens remain on the surface of the skin and act like a barrier reflecting UV rays. They offer wide spectrum protection, that is to say that they protect both the UVA and UVB rays. This cream protects you from its application.
Here is a table taken from the Acne.org site3 Who lists the protective photo ingredients and their ability to protect the skin from UVA and UVB. We see that no ingredient is as effective as zinc oxide.
Mineral powders are not all without danger. In the case of zinc oxide and titanium dioxide, there are different kinds on the market, some of which can contain nanoparticles. It is a very small particle with a diameter of less than 100 nm (nanometer). The advantage is that it gives mineral creams that reduce the white effect on the skin. But since nothing is perfect, nanoparticles can enter the pores of the skin and obstruct them. They are dangerous to handle because their inhalation is a source of pulmonary inflammation. They can affect microbiota in addition to damaging ecosystems.4 It is really important to use these last two ingredients without nanoparticle.
Zinc oxide
The Champion of Protective Photo Ingredients par excellence! It reflects both the UVA and UVB rays. The idea is to distribute a thin layer of zinc oxide on the surface of the skin. This white layer will reflect the rays and prevent your skin from burning. The application of a sunscreen that contains zinc oxide requires a little more time. You have to massage well to disperse the cream and reduce the white effect on the skin. Depending on your skin type, the zinc oxide layer can be almost invisible to the naked eye.
The use of certain ingredients in your formulas will help dispersion of the zinc oxide.
The stearate glyceryl citrate is an emulsifier that gives more liquid creams, which is perfect for adding zinc oxide. The liquid the cream, the easier zinc oxide is distributed over the surface of the skin. In addition, this emulsifier tolerates the assets that protect against UV rays.
I'Olivem 1000 is another emulsifier that promotes the dispersion of powders. Dosed at 4%, without co-emulsifier, it gives a cream liquid enough to add the zinc oxide.
Coco caprylate is an emollient that looks like a dry oil. This asset slides the cream over the skin, which reduces the whitening effect to the application.
The application of raspberry seed oil On the skin before applying zinc oxide cream helps reduce the whitening effect on the skin in addition to protecting it from sunburn.
The addition of iron oxides or Micas in very small quantities can color your cream.
In your formulas, use 15% to 20% zinc oxide which will be added once your cream has cooled. Make a liquid cream to facilitate the application with good oils that will help sun protection.
Titanium dioxide
We often see titanium dioxide in combination with zinc oxide in mineral solar creams, but we consider that the use of zinc oxide is sufficient. In France, this ingredient is prohibited by the European Food Safety Authority (EFSA) Since 2021 for its use as a food additive. It is also found in toothpaste. In Canada, he is suspected of being a carcinogen so inhaled.5 It is definitely harmful to the seabed (whitening of corals and microorganisms).
What do FPS, SPF and IP mean?
THEFps is the abbreviation of " Factor ofProastingSolaire ”, theSPF comes from English " SaburnProastingFactor "and theIP is the abbreviation of " Indice ofPRotection ”. They all want to say the same thing.
The number after the FPS represents the value of the UVB ray protection index. It is therefore this issue that is important to look. There are four levels of protection.
- Weak protection, between 6 to 15
- Mean protection, between 15 to 25
- Strong protection, between 30 to 50
- Very strong protection, between 50 and more
How to know which FPS index is suitable for me?
The protection index is actually a time indicator. The more your skin blushes quickly when exposed to the sun, the more you need to use a high UV protection index. If your skin blushes after 15 minutes of exposure and you use an FPS 30 cream, you must multiply your exposure time without protection with the FPS protection index. So 15 minutes x fps 30 = 450 minutes or 7:30 am. However, this calculation remains very theoretical. Sweating, water and friction of clothes on the skin are all factors that can reduce the effectiveness of your sunscreen. This is why it is recommended to apply it within 2 hours.
In 1975 Thomas B. Fitzpatrick 6, an American dermatologist, classified individuals according to the reaction of their skin during a solar exposure. Fitzpatrick's classification distinguishes 6 types of phototypes. This classification helps us to better understand the relationship between melanin and the effects of UV rays on our skin. Melanin is a set of dark organic pigments that are responsible for coloring our skin. It naturally filters UV rays, but is not effective enough. Even for a phototype VI, it is advisable to use an FPS30. Phototype I skin has the advantage of using a cream with an FPS50. This classification will help you make an appropriate choice of sunscreen.
Phototypes |
Skin color |
Hair |
Eyes |
Sun tanning |
Sun burn |
Phototype I (melanocompromis) |
Very white |
Blonds \ Roux |
Blue \ green |
No tanning |
+++++ |
Phototype II (melanocompromis) |
Clear |
Blonds \ Roux \ Chestnuts |
Green / Brown |
Barely |
+++ |
Phototype III (melanocomumping) |
Moderately clear |
Small / brown |
Chestnuts |
Progressive tanning |
Casual |
Phototype IV (melanocompaist) |
Mate |
Bruns \ Blacks \ Brown |
Black |
Easy tanning |
Rare |
Phototype V (melanoprotegée) |
Mattress |
Black |
Black |
Tanning +++ |
Very rare |
Phototype VI (melanoprotegée) |
Black |
Black |
Black |
- |
Never |
Source :https://dumas.ccsd.cnrs.fr/dumas-03367834/document
Vegetable oils and their FPS
Vegetable oils and essential oils may contain active molecules or fatty acids that are protective photos at different levels of intensity. Rutin, caffeine, ferulic acid, tocopherol and carotenoids are examples.
Oils vegetable and essential |
Fps between |
28 and 50 |
|
38 and 40 7 |
|
10 and 30 8 |
|
6 and 8 |
|
11 |
|
6 |
|
4 |
|
2 and 4 |
* It is difficult to find a reliable source on the FPS of karanja oil, but reference #8 shows that it has an effect.
Zoom on our two stars!
Raspberry seed oil
A beautiful solar oil which gently protects the skin to the exposure of the UVA and UVB rays. It partly absorbs the shelves, thus offering very interesting sun protection. It contains carotenoids, including the beta-carotene which is a protective photo. Some studies 9 have shown that its FPS protection could be between 28 and 50. It is a "must" in our solar products. It is also restorative, nourishing, healing and antioxidant, then she reduces redness, calms irritation and eczema, then gives tone and helps fight the aging of the skin. We are waiting for this oil made in Quebec with Quebec!
Essential carrot seed oil
With antioxidant, antiseptic properties and a high rate of vitamin A, this essential oil is in the top of natural ingredients that protect the skin from UV rays. You can dilute it with a Carrier oil Or add it to your formulation of home sunscreen.
Karanja oil
Originally from India, karanja oil contains two protective photo flavonoids, pongamol and karanjine. This exceptionally active oil has emollient properties and is interesting in the formulation of anti-aging care to combat the signs of skin aging, especially those linked to the sun. This oil is ideal in hair care recipes for its nourishing, protective (coloring) and solar properties.
Some basic notions for those who make their homemade sunscreen.
ATTENTION !
FPS do not add up. If you use carrot seed essential oil (FPS 38) diluted in karanja oil (FPS 20), you cannot say that the FPS is 58 for example. You cannot give FPS value to your product unless you have your laboratory product tested.
To market a sunscreen with an FPS mention, you must go through a laboratory, then by Health Canada and apply for a natural health product license (which first requires an operating license). Sun cream is not considered a cosmetic product, but as a natural health product.
Good summer ! ☀️
References
1 https://www.canada.ca/fr/sante-canada/services/securite-et-risque-pour-sante/radiation/categories-sources/ultraviolet.html
2 https://www.acne.org/do-physical-sunscreens-absorb-ultraviolet-uv-radiation
3 https://www.acne.org
4 B. Nowack, The behavior and effects of nanoparticles in the environment, Environmental pollution, flight. 157, noto 4, April 2009, p. 1063-1064 (Summary [archive])
5 https://www.cchst.ca/oshanswers/chemicals/chem_profiles/titanium_dioxide.html
6 https://fr.wikipedia.org/wiki/Classification_de_Fitzpatrick
7 https://fre.toasthomestylebreakfast.com/natural-oils-that-contain-spf-5585
8 http://greenpharmacy.info/index.php/ijgp/article/view/159
9 https://www.researchgate.net/publication/215523935_Characteristics_of_raspberry_Rubus_idaeus_L_seed_oil
Sources of inspiration
https://www.typology.com/carnet/spf-20-30-40-50-que-ce-que-cela-signifie
https://www.aroma-zone.com/info/dossier-thematique/les-indices-uv-et-le-bronzage
https://www.cancer.net/blog/2022-04/answers-your-questions-about-sunscreen-ingredients
- Myriam Leduc