What is SPF?
Refers to the SPF (Sun Protector Factor) or in Portuguese FPS, Sun Protection Factor which is a factor related to protection against UVB rays and which allows you to increase the time of sun exposure without suffering a burn. For example, if 5 minutes is the time it takes for a person with a low phototype to develop solar erythema, that is, redness, an SPF of 30 multiplies by 30 times that time, that is, it would take 150 minutes, two and a half hours. In practice, this is not quite the case because the sunscreen should be applied in a generous amount and in an even layer. The amount to be applied should be 2mg of sunscreen per cm2 of skin, which is equivalent to 1 teaspoon for the face or 3 fingers and a golf ball for the body. SPF is universal and follows ISO standards, and it is expected that an SPF 50 will provide the same level of protection whether in Europe, Asia or America.
They exist 4 levels of protection:
- Low (SPF 6 to 10)
- Medium (SPF 15-25)
- High (30 to 50)
- Very High (50+)
We recommend using High 30-50 or Very High 50+.
The protector must still be reapplied every 2 in 2 hours, after showering or drying yourself with a towel and after heavy sweating. Don't forget that UVB radiation is responsible for burns and tanning, allergic reactions and skin cancer.
What is PPD (Persistent Pigment Darkening)?
The protection factor against UVA radiation is given by the PPD factor, which is generally not mentioned on sunscreen packaging. The European Union recommends that it be at least 1/3 of the SPF – with an SPSF of 30, the protection against UVA rays would be at least 10. When sunscreens meet this requirement, they have the following characteristics: GRAPE symbol within a circle.
Protection against UVA radiation is very important because it is responsible for photoaging (changes in collagen and elastin fibers, wrinkles, sagging), sun intolerance and skin pigmentation (melasma, dark spots).
What are filters?
Filters are the physical or chemical substances present in sunscreens that are responsible for its protective power against radiation and which are present in the formulations in addition to excipients such as water and other active ingredients such as hyaluronic acid, niacinamide, antioxidants and others.
What are the differences between chemical and physical filters?
Chemical filters (Octocrylene, Avobenzone, Octinoxate, Oxybenzone, Hemosalate, Tinosorb, Meroxyl):
- absorb radiation, modifying it and emitting it back
- have a greater spectrum of UNV protection in addition to UVB
- allow to formulate sunscreens that are more fluid, transparent and without white residue
- may have greater irritating potential.
Physical filters (Titanium Dioxide, Zinc Oxide):
- absorb radiation, emit it and reflect some of it
- have a broad spectrum of UVB protection
- can leave white residue and thicker protectors.
Are mineral sunscreens better than physical ones?
The answer is depends: physical filters should be preferred in babies up to 1 year old age, in some specific cases such as very sensitive and reactive skin and in athletes.However, the most chemical filters can be used with safety without the risk of causing allergic reactions They allow for more fluid, transparent and residue-free formulations with a wider UVA protection spectrum. The misconception that physical filters are “inert” and safer for sensitive skin arose in the USA because, as they have few chemical filters approved by the FDA (they are in the 90s compared to Europe), and one of them being Avobenzone, which is one of the most sensitizing, they are often recommended over chemical filters. In Europe, we can safely opt for the best of both worlds and use protectors with physical and chemical filters.
How to choose sunscreen:
When choosing a protector, you must take into account several factors such as:
- have broad spectrum protection UVB, UVA, IR, HEV, Blue Light
- be water resistant
- have good ophthalmic tolerance (do not irritate the eyes)
- have sufficient capacity for the time of application (holidays, the whole family)
- contain antioxidant and repairing active ingredients in the formula
- be correct for that circumstance (practicing water sports, daily use)
- be directed to a given stage of life (babies, children)
And remember that the best protector for you has to be one that adore, since, in the case of your face, you will use it every day. It should therefore be sensorially pleasing and have a smell, texture and finish that you like and leave your skin feeling comfortable so that you want to use it every day.
Can body protectors be used on the face?
In theory yes, but since the skin on the face and body have different characteristics, it should be possible to use two different. In addition, face protectors can be colored and are generally less greasy, formulated with milder ingredients and without added perfume. They are also useful in cases of special needs or pathologies such as acne, rosacea, blemishes, wrinkles, and sensitive eyes.
Can I use last year's sunscreen?
Again, it depends. If you are unopened, within the expiration date and stored away from high temperatures and humidity – Yes. If it has already been used, you must check that it is within the expiration date and the post-opening period (PPA) that appears on the packaging with the product. symbol of an open jar and the indication of the months (usually from 6 months to 12 months), if it was well stored and if does not present changes in smell, color, texture and consistency. It should also be rejected if you notice that your skin turns red in a short period of time (the filters may have been changed, resulting in a loss of effectiveness).
How to store sunscreen?
Keep in a cool, dry place (the refrigerator and bathroom are not suitable), at room temperature and away from direct sunlight. Do not leave it in the sun on the towel, close it tightly and place it in the shade. Avoid leaving it in the heat in the car to prevent alteration of the filters.
What does it mean to be water resistant?
Being water resistant means remain effective for 40 minutes on the skin wet and be very water resistant, remain effective for 80 minutes. Very water-resistant ones should be preferred for children and athletes.In real conditions, with salt water, chlorine or waves, they may not maintain the same effectiveness time as that obtained in the tests. No sunscreen is 100% effective and resistant in real conditions, there is always some loss of effectiveness with water or sweat.
If I use sunscreen, can I be exposed to the sun for as long as I want?
No, should only be exposed to the sun when it cannot be avoided, such as when bathing, drying yourself and staying in the shade whenever possible. You should also take additional precautions such as wear a hat wide-brimmed or cap, sunglasses, dark clothing (t-shirt), also protect the lips (balms or lip sticks with SPF), ears and the backs of hands and feet. Also avoid exposure during 12 and 16 hours or in low phototypes between the 11 am and 5 pm. Do not go to tanning salons.
When do I not need to use sunscreen?
You don't need to use sunscreen:
- at night
- in the shower
- in a cave. 😄
