What are the right steps to protect a baby's skin from the sun?

The skin of a newborn is different from that of an adult and is thinner and more fragile. Indeed, the skin barrier gradually develops after birth and will not be able to fully perform its protective function until the age of six. The physiology of baby's skin is thus different before this age. Moreover, the melanin synthesis process is only partially developed in children under three years old, making them more vulnerable to the dangers of the sun.

Indeed, when exposed to sunlight, the epidermal cells undergo the attack of UVA and UVB rays, which can lead to metabolic defects, the degradation of cellular constituents and the development of melanomas. To protect itself from the damage caused by UV rays, the body initiates a defense mechanism and promotes melanogenesis. The produced melanin clusters around the nucleus of the keratinocytes to form a veil with the aim of protecting the DNA from the mutagenic and carcinogenic effects of ultraviolet rays. However, the concentration of melanin is lower in young children, thus the risks posed by sun exposure are greatly increased. Several studies have indeed shown the existence of a link between children's UV exposure and the development of melanoma in adulthood.

Still fragile and vulnerable, a baby's skin must absolutely avoid direct exposure to the sun's rays. Studies have indeed established that there is a strong correlation between thesun exposure of young children and the development of melanoma once they become adults. Therefore, to prevent these risks, it is good to adopt certain practices during family outings.

Limit your outings between 12 p.m. and 4 p.m.

During very sunny days, it is recommended to avoid taking the baby out for walks between 12pm and 4pm, the time of day when the sun's ultraviolet rays are most intense and therefore most dangerous, even in the shade. Indeed, it's important to note that UV rays can be reflected by various surfaces (water, sand, snow, asphalt...). It's also crucial to be wary of the shade created by clouds as a mid-altitude cloud layer only stops 30 to 60% of the sun's rays.

Opt for clothing that provides coverage.

To protect your child, it is also recommended to have them wear covering clothing, such as a long-sleeved shirt, pants that cover the legs, and a wide-brimmed hat. Opt for loose and easy-to-put-on clothing. For color, we advise you to avoid dark colors that tend to retain heat and promote sweating. There are also UV-protective clothing designed to combat ultraviolet rays: these have a UPF (Ultraviolet Protection Factor or UV protection index) that indicates their degree of protection. For example, a UV-protective t-shirt with a UPF 50 only allows 1/50th of the UV rays to pass through. Finally, don't forget to give your baby sunglasses to protect their delicate eyes.

Do not neglect the sunscreen.

Even if the baby stays in the shade, which is highly recommended, it is advised to apply a sunscreen of at least SPF 50 to the parts of their skin that are not covered. Opt for sun care products that are free from fragrances, allergens, or alcohol derivatives, which can potentially irritate a baby's skin. Moreover, it is preferable to use only mineral filters for children under two years old, due to their skin's high permeability and the risk of allergies.

To ensure the effectiveness of sunscreens, the application of sunscreen should be done about 20 minutes before going outside and should be renewed every two hours in case of prolonged exposure. To facilitate its application, there are spray sun care products for children. Make sure to apply enough to achieve the protection factor value indicated on the label, which is 2 mg per cm2 of skin, corresponding to 12 to 15 sprays with spray sunscreens. Finally, don't forget to apply it to the back of the neck and behind the ears, areas often overlooked.

Regularly hydrate your baby.

Even when avoiding the hottest hours of the day, it's crucial to keep your baby well-hydrated, especially during summer when the sun brings both UV rays and high temperatures. Their formula bottle or breastfeeding helps to keep them hydrated, but, when it's very hot, it's also important to offer them water. In addition to keeping them hydrated, this willprevent heatstroke. A misting spray can also help to cool them down.

• PUGLIESE P. The skin, free radicals, and oxidative stress. Dermatology Nursing (1995).

• KOLLIAS N. & al. Infant skin physiology and development during the first years of life: a review of recent findings based on in vivo studies. International Journal of Cosmetic Science (2010).