With summer’s arrival and rising temperatures, families may have doubts about the most appropriate sun protection to choose for themselves and their children.

The importance of sun exposure for any living being and also the need for protection to avoid skin problems are well known. Sun protection is a key element for this time of the year, as well as choosing the one that best suits each situation.

Sunlight

The sun emits energy in the form of radiation, a mixture of rays or waves. Some are harmless, such as long waves, and others are more harmful, such as ultraviolet radiation.

But it’s also the ultraviolet (UV) radiation that promotes vitamin D synthesis and tissue damage at the same time.

UV radiation is classified into 3 main types: UVA, UVB, and UVC. The ozone layer completely absorbs UVC radiation and much of the UVB radiation. Therefore, the waves received on Earth are UVA and part of the UVB.

• UVA: UVA rays penetrate the skin and are responsible for sun tanning. Consequently, they accelerate skin aging and the appearance of wrinkles.
• UVB: UVB rays penetrate the skin only slightly and are responsible for skin burns.

Risks and benefits of the sun

The sun is essential for living beings and provides important benefits such as:

• Helping the body with the synthesis of vitamin D
• Anti-inflammatory effect against some dermatological diseases: promotes healing of psoriasis lesions and some dermatitis and helps to prevent and control skin acne.
• Improves sleep cycles as it regulates melatonin supply.
• Improves the mood.

As for Vitamin D: this helps the body to absorb calcium and phosphorus from food and contributes to bone formation, avoiding conditions such as rickets or osteoporosis, as well as playing an important role in the nervous, muscular, and immune systems. On the other hand, vitamin D deficiency leads, among other things, to fatigue, pessimism, depression, muscle weakness, nervousness, or insomnia.

Therefore, the importance of sunlight in our health is understood. However, it can also be harmful if there is constant and uncontrolled exposure to sunlight without appropriate protection.

Sun protection creams

Sun protection in the form of cream, lotion, or serum uses the acronym SPF (Sun Protection Factor) to indicate the time of exposure to the sun to avoid sunburn.

The SPF measures the protection against UVB; as UVA is variable and its measurement is complicated and applying sun cream or lotion every 2 hours at the most or after swimming is recommended.

There are two types of filters for sun protection:

• Mineral filters: they are not absorbed through the skin, causing UV light to bounce back most of its radiation, thus preventing it from entering the skin. They are not absorbed, especially if they are not formulated as nanoparticles. Typically the components used are titanium dioxide and zinc oxide.
• Chemical filters: They penetrate the skin and perform their action by absorbing radiation and transforming it into harmless radiation.

Sun protection in pregnancy, breastfeeding, and babies

It is known that several chemical sunscreen filters act as endocrine disruptors and are susceptible to affecting the genital-sexual system and the hypothalamic-pituitary-thyroid axis of the infant. In various studies, these compounds have been found in human milk in varying amounts, although much lower than the necessary doses studied with endocrine-disrupting effects.

In any case, the long-term effects of chronic exposure to endocrine-disrupting chemical sunscreens are unknown, so physical sunscreens are preferable during breastfeeding (5).

In the case of protection for babies, the general recommendation is to avoid sun exposure in the central hours of the day and, if necessary, the use of sunscreen with a high SPF, broad-spectrum physical filter is recommended for infants older than 6 months of age. It should be applied prior to sun exposure and every 2 hours or before going into the water. Other measures can be added, such as the use of sunglasses, sun hats, and sun-protective clothing. This clothing is labeled with the acronym UPF, Ultraviolet Protection Factor, similar to the sun protection factor, but for fabrics.

As for the stages of pregnancy and breastfeeding, there are not enough studies on the use of sun protection, although the recommendations seem to point to prefer the use of physical protection and, if possible, without the presence of nanoparticles. In the case of breastfeeding, it is also advisable not to apply sunscreen on the breast area.

 

References:

1. https://www.elsevier.com/es-es/connect/ciencia/beneficios-salud-del-sol
2. MedlinePlus en español [Internet]. Bethesda (MD): Biblioteca Nacional de Medicina (EE. UU.) [actualizado 27 ago. 2019]. Vitamina D; [actualizado 12 noviembre 2021; consulta 16 jun. 2023]; [aprox. 5 p.]. Disponible en: https://medlineplus.gov/spanish/vitamind.html
3. https://www.cdc.gov/nceh/radiation/nonionizing_radiation.html
4. https://www.cdc.gov/spanish/nceh/especiales/radiacionuv/index.html#:~:text=La%20radiaci%C3%B3n%20ultravioleta%20(UV)%20es,causar%20riesgos%20para%20la%20salud.
5. https://www.e-lactancia.org/breastfeeding/topical-sun-protector-cream-lotion-gel/synonym/