Sunscreens are inseparably linked with summer, when they help us prevent sunburn. However, using a sunscreen with a protection factor has other benefits as well. Find out more about sunscreens and about the raw materials that have the ability to reduce the negative effects of the sun on the skin.
We will go through how to make a sunscreen and what UV factor vegetable oils have.
The sun and skin: why you should protect yourself
In addition to visible sunburn, redness or itching of the skin after excessive exposure to the sun, sun rays also have other negative effects on the skin. Excessive exposure to the sun is associated with a higher risk of developing skin cancer. Sunbathing accelerates the ageing of the skin, or the formation of pigment spots.
For this reason, it is good to have a sunscreen in reserve and to use it ideally on the face, and possibly the hands, throughout the whole year. Thanks to the proper protection of the skin, you can prevent its excessive sun damage or slow down the signs of ageing.
How sun protection works
What should you pay attention to when choosing the right sunscreen or when preparing your own sun product? Sometimes it is not easy to navigate the large amount of available information. Below you will therefore find an explanation of the terms associated with sun care products — with these you can then make sensible decisions about a homemade recipe as well.
Mineral UV filters
In natural cosmetics, you most often encounter mineral UV filters. The substances that provide such protection are zinc oxide and titanium dioxide. These raw materials are commonly available for making cosmetics, so you will not find them only in commercially available products.
Both substances are fine white powders, and therefore after applying sun care products containing mineral filters a fine white film sometimes remains on the skin (mainly caused by a higher content of titanium dioxide).
For this reason, brown, yellow and red iron oxides are sometimes added to products containing these substances; they tint the cream, so that in one step they serve both as sun protection and as make-up. That is why mineral make-up that contains titanium dioxide and zinc oxide naturally shows an SPF factor.
Mineral filters most often work on the principle that they create a protective layer on the skin through which the sun’s rays do not penetrate, or from which some of them are reflected.
Beware of nanoparticles: it is good to choose titanium dioxide and zinc oxide whose particles are larger than nano (10⁻⁹ m), in order to minimise the penetration of these substances into the skin. The disadvantage of nanoparticles is that they are very small and can penetrate deeper into the layers of the skin, and the effect of such substances on the body has not yet been sufficiently studied in terms of long-term exposure.
Chemical UV filters
Chemical UV filters, unlike mineral ones, do not remain on the surface of the skin. On the contrary, they are absorbed by it. The advantage of chemical filters is that they are usually effective even at lower concentrations, so the products are less greasy or sticky. At the same time, they do not leave a white film on the skin.
The disadvantage is that over time the chemical protective filters break down due to sunlight and the cream has to be applied frequently. In addition, some chemical compounds used as UV filters are associated with the development of cancer and have been observed to spread from the skin to other parts of the body.
When making homemade products, it is usually difficult to obtain chemical protective filters, which is why homemade products focus on mineral filters and oils with protective properties.
SPF: the sun protection factor
The sun protection factor, or SPF, expresses how a given product or raw material protects against the sun, specifically against UVB radiation, which has slightly more severe consequences for the skin than UVA radiation. It is advisable to use protective products with higher SPF values, ideally 30 and above.
At the same time, it is desirable that the product is always broad-spectrum, i.e. that it protects against UVB rays, which are associated with skin cancer, but also against UVA rays, which have a slightly less destructive effect on skin cells than UVB rays. Nevertheless, UVA rays can accelerate skin ageing.
Homemade sunscreens: what to check
Before we go any further with explaining the properties of the individual raw materials that show certain SPF values, it is necessary to emphasise the disadvantage of making homemade sun protection products. This is the fact that under home conditions you cannot verify the effectiveness of your product against the sun, i.e. what SPF factor your product has. The exact determination of the SPF value of a product requires laboratory analysis.
Important: if you are not sure that your product provides sufficient protection, combine it, where possible, with a proven product. This applies especially in the case of skin diseases, sensitive, fair or children’s skin, or skin prone to sun allergy, but also during days with intense solar radiation.
At the same time, working with titanium dioxide and zinc oxide, which are most often used to make homemade sun care products, is very demanding. It is difficult to achieve a mixture in which these oxides are evenly dispersed; without a balanced distribution of the particles of these oxides you will not obtain an effective protective cream.
Tip: one of the options for preparing a homemade sun care product with a known SPF value is to use ready-made bases for making sun protection products. Such bases have a declared SPF and instructions from the manufacturer for mixing them with other substances (for example oils or creams). At the same time, it is stated what SPF factor you will achieve if you use a given percentage of the base to make a sunscreen.
Oxides for homemade creams
Various cosmetic raw materials also show protective effects against the sun. These are mainly oils and some oxides. As mentioned, the exact SPF factor of these raw materials can only be verified in a laboratory, and at the same time each batch of oil is slightly different, because it is made from the fruits of different plants that have faced different fluctuations in weather, water and so on. Let us start with the two oxides on which homemade mineral protection is built.
Zinc oxide
Zinc oxide is the most popular substance for making homemade sunscreens, but you will also find it in a whole range of commercially available products, from natural sunscreens to decorative cosmetics. There, too, zinc oxide plays an important role, so if you make mineral make-up, it is zinc oxide that provides a certain degree of sun protection in it.
Zinc oxide combines well with other oxides, especially titanium dioxide and iron oxides or chromium oxide, which are used together as colour pigments – they help to match make-up or a sun care product to the skin tone so that you avoid white streaks from otherwise pure titanium dioxide and zinc oxide.
The approximate dosage of zinc oxide is as follows:
| SPF | Zinc oxide content (%) |
|---|---|
| 2 – 5 | 5 |
| 6 – 11 | 10 |
| 12 – 19 | 15 |
| 20 | 20 |
Again, these are only approximate values, since under home conditions it is not possible to verify the exact protection factor.
Titanium dioxide
Titanium dioxide is another oxide used in preparations with mineral filters. Thanks to the presence of titanium dioxide, creams cover well and mechanically prevent the penetration of sun rays or reflect them from the skin. At the same time, a higher proportion of titanium dioxide in the mixture means that creams can leave a white film on the skin.
Titanium dioxide is an opaque white substance; you will also appreciate it when making homemade make-up, because it increases its coverage. It is available in a version for incorporation into oil-based or water-based mixtures.
Vegetable oils and their SPF
Important: oils alone do not represent satisfactory protection against the sun. If you want sufficient sun protection, it is best to combine them with sunscreens. In this way you get the benefits of oils for the skin together with sun protection.
The values below are approximate — for each oil they vary according to the quality and age of the raw material. For a quick comparison:
| Raw material | Approximate SPF |
|---|---|
| Wheat germ oil | around 20 |
| Avocado oil | 4 – 10 |
| Coconut oil, virgin | 2 – 8 |
| Olive oil | 2 – 8 |
| Raspberry seed oil | 6 – 7 |
| Hemp oil | around 6 |
| Shea butter | 3 – 6 |
| Jojoba oil | around 4 |
| Macadamia oil | around 4 |
Raspberry seed oil
Raspberry seed oil, also called raspberry oil, is one of the most commonly used oils in products for sun protection. Its SPF is only in the range of 6 – 7, but it can vary, as with other oils, depending on the quality of the seeds from which it was pressed. Likewise, raspberry oil that has been stored for too long, has oxidised or has often been exposed to the sun may have minimal or no protective effect against the sun.
Raspberry oil perfectly complements products containing oxides. You can thus increase the protective effect of your creams, oil serums or lip balms. You can also use it to dilute thicker commercially available creams with mineral protective filters if you feel that they are difficult to apply to the skin.
Wheat germ oil
Wheat germ oil, obtained from an unconventional source, can also provide the skin with some protection against the sun; its SPF is around 20 — the highest value among the oils in this overview, although it still holds that the SPF of a homemade product cannot be verified under home conditions. Wheat germ oil is rich in vitamins, especially vitamin E, K and B-group vitamins, and it also contains minerals and unsaturated fatty acids. Together with other substances, it helps protect the skin against free radicals formed by solar radiation.
Avocado oil
Avocado oil is suitable not only for the kitchen — treat your skin to it as well. Its protection factor SPF is in the range of 4 to 10. Avocado oil complements many types of cosmetics perfectly; it has a darker colour, so you should expect that it may change the colour of white creams or balms.
Coconut oil
Virgin coconut oil also shows some protection against the sun, but a relatively small one. Its SPF is in the range of 2 to 8. If you like the coconut scent, this oil is an excellent addition to body butters or products for dry skin.
If you want neutral, fragrance-free products, there is also a deodorised form of coconut oil, but during the processing of the oil some of the active substances responsible for skin protection may have been lost. Coconut oil contains a higher proportion of saturated fatty acids compared with other vegetable oils, and it can clog pores, especially on skin prone to acne. For this reason, if you have oilier skin, reach for other vegetable oils, for example jojoba oil.
Jojoba oil
Jojoba oil is a great option for nourishing even sensitive skin or skin prone to acne. Jojoba oil is rich in minerals, vitamins and unsaturated fatty acids, it is well absorbed by the skin and leaves less of a greasy feeling than most oils. Its protective SPF factor is around 4.
Olive oil
The versatile olive oil also has a protection factor against the sun; specifically, it has an SPF of 2 to 8. Olive oil is affordable, but nevertheless full of antioxidants and protective substances such as vitamins A, C, E, B1 and B6, as well as proteins and minerals. If you choose olive oil for its protection factor, reach for extra virgin olive oil.
Hemp oil
Hemp oil is notable for its protection factor, which is around SPF 6. Hemp oil is obtained by pressing hemp seeds. It contains valuable fatty acids, especially gamma-linolenic acid (GLA), and improves the condition of wrinkles. It helps prevent moisture loss from the skin and will also be appreciated by acne-prone skin, because it is quickly absorbed.
Shea butter
Shea butter also has its own protection factor against the sun; specifically, its SPF is in the range of 3 to 6. Because shea butter is a solid fat, you will appreciate it especially in solid products such as lip balms or various protective creams and whipped butters. It helps reduce the melting of whipped butters and balms during hot days (in which case it is recommended to combine it with beeswax).
Macadamia oil
For exotic macadamia oil, the SPF is around 4. Macadamia oil is primarily suitable for mature skin, because it helps smooth wrinkles and improve the condition of the skin. However, its use is not limited by age. Oilier skin will also appreciate it, because it spreads well and does not leave a greasy film.
Conclusion
Healthy sunbathing can sometimes be a real science. We believe that in this article you have clarified with us all the terms that are important to know if you want to make your own sunscreen.
Have you ever made your own sunscreen? How did it go?
You can send us the answers to these questions by e-mail to [email protected]. Do not hesitate to write your opinion, experience or questions that trouble you. We will be happy to answer you.
Thank you for your favour and, until we see each other again, we wish you a beautiful day.
You will find mineral filters and tinting pigments in our range of oxides, and protective oils among the vegetable oils.
