Sunscreen

The importance of sunscreen:
Sunscreen is a topical health and wellness product that protects your skin from the sun’s ultraviolet (UV) rays. It is effective when it has an SPF of at least 30 (recommended by the American Academy of Dermatologists).

This SPF is a numerical estimate of how well a product protects your skin from ultraviolet B (UVB) radiation. It represents the ratio of the time it takes for ultraviolet rays to produce a sunburn with or without sunscreen. An SPF of 30 means that you can stay out in the sun 30 times longer without getting a sunburn. It also indicates the proportion of UVB rays blocked: an SPF of 15 blocks 93% and an SPF of 30 blocks 96.7%. So you can’t superimpose the indices.

The sunscreen should also be broad spectrum to protect your skin from the sun’s UVB rays as well as ultraviolet A (UVA) rays.

While UVB rays are more closely linked to skin cancer, UVA rays can still damage your skin and penetrate deep into the layers of your skin to accelerate wrinkles. That’s why a broad spectrum sunscreen is a better bet for sun protection.

The role of sunscreen is to protect against UV rays by forming a barrier on your skin to prevent the absorption of UV rays.

There are two types of sunscreens you can buy:

Chemical sunscreens work by binding to the skin, absorbing UV rays and converting them into heat
Physical or mineral blockers – aka zinc oxide and titanium dioxide – are like a force shield. They coat the skin and the UV radiation is reflected by the sunscreen particles. These usually leave a white trace on the skin if they are not tinted.

You can choose between the two types of sunscreen, but when choosing the physical sunscreen, look for those with a minimum 10% concentration of zinc oxide to achieve broad spectrum coverage.

To be effective, sunscreen should be reapplied every two hours. For those who wear make-up, spray sunscreens are available and are very practical.

However, make sure you don’t inhale titanium dioxide, and to a lesser extent zinc oxide, in the aerosol or spray versions of mineral sunscreens. Because they can damage the lungs.

Some advice

There is no evidence that sunscreen is bad for your health. Although an FDA study in 2020 found that the body can absorb certain chemicals for some sunscreens, it has not been proven to have any adverse health effects.

This FDA study published in JAMA in 2020 found that the body absorbs unusually high levels of certain active ingredients that are common in chemical sunscreens. These ingredients are avobenzone, oxybenzone, octocrylene, homosalate, octisalate and octinoxate.
However, there is evidence that not protecting yourself from the sun’s UV rays can increase the risk of several types of skin cancer.

It doesn’t matter if it’s an occasional high dose or just a lifetime of moderate sun exposure. Both will damage your skin cells and increase your risk of cancer. You may simply develop a different type of skin cancer depending on your circumstances.

Sun damage accumulates over time and is irreversible, which is why it is so important to get into the habit of wearing sunscreen.

The sun exposure we get in our 20s, 30s and 40s, we won’t see the effects until 20 years later, both in terms of ageing and skin cancer effects.”

There is no evidence that mineral sunscreens significantly penetrate the skin, making them a safe alternative for those concerned about the ingredients in chemical sunscreens.

If you have concerns about sunscreens, discuss them with your dermatologist.

Exposure to the sun is essential for our bodies to synthesise vitamin D, without which normal growth is impossible for our children, and without which our bones and teeth deteriorate. It is this vitamin that allows the absorption of calcium and its fixation on our bones, and a good absorption of phosphorus by our intestines. A lack of vitamin D can cause serious health problems. It is found in the diet, but daily exposure to UVB rays is necessary for its transformation by our body.

A quarter of an hour of exposure per day without sun protection is recommended for light skins, more for dark skins and black skins for which the recommended ratio can be multiplied by up to 20 depending on the person. This daily exposure is recommended without sunglasses, which send false information to our brain and prevent it from quantifying the UV rays present in the atmosphere. This blocks the process of vitamin D synthesis. A visor or a hat with a wide brim can be used instead.

Please note that artificial tanning in UV cabins does not allow the synthesis of vitamin D by the human body.

Apply sunscreen every two hours when exposed to direct sunlight.
Avoid direct sunlight during peak hours, usually from 10am to 2pm. (peak hours may vary depending on your location and the time of year)
Wear wide-brimmed hats at least four inches in diameter.
Wear sunglasses with wide lenses to avoid sunburn.
Apply sunscreen to face, neck, chest and hands

Sunscreen is essential. This is often questioned, especially during the colder, greyer months of the year and on days when the sun is hiding. But one thing you should know is that the need for SPF is real, regardless of the weather, season or temperature.

The sun is the number one cause of wrinkles, with dozens of studies documenting the impact. Regardless of your skin tone or colour, wearing sunscreen year-round will prevent skin damage from UV rays, minimizing your risk of skin cancer and premature aging. In addition, the sun’s rays can still penetrate on cloudy days, when it is cold and raining, and even through windows.

Glass windows filter out UVB rays, but UVA rays can still penetrate through, which is harmful to your skin. UVA rays actually penetrate a deeper layer of the skin and are therefore more damaging than UVB rays. In fact, UVA rays cause hyperpigmentation, skin cancer and premature aging. All of this is to say that even if you plan to spend an entire day indoors, supplementing your skin care routine with a final layer of SPF is a necessary idea.

As a general rule, Johns Hopkins medical experts recommend reapplying sunscreen every two hours. That said, if you are indoors and away from windows, the need to reapply is less necessary.

While not all sunscreens protect against blue light, i.e. light emitted from screens (whether it’s your phone, laptop or TV), those formulated with zinc oxide and/or titanium dioxide do. In fact, according to a clinical trial published in the British Journal of Dermatology, researchers found that sunscreens containing microfine titanium dioxide offered significantly more protection against UVA and blue light than the other SPFs in the trial.

Like any cream, sunscreen can deteriorate and the ingredients can break down, leading to a watery consistency. And as the ingredients degrade, the sun protection qualities also become less effective, compromising the integrity of the product and exposing you to serious sun damage.

Proper storage is also important. Heat and humidity also accelerate the degradation of sunscreen, so make sure you keep it at a cooler or room temperature (so storing it in your car is not ideal).

Sunscreen expires, and you can tell if it has expired by the expiry date or by a change in consistency or smell. If in doubt, throw it away. Just as you would with any other over-the-counter or prescription medication, or even perishable food.