Beach, pool, hike, picnic by the lake… As soon as the first rays of sun appear, our summer weekends fill up with outdoor activities. In our backpacks, the season’s must-have: sun protection! But do you know exactly what it contains and whether it’s safe for your health and the environment? Follow us — we explain everything.
The sun: friend or foe?
The sun has several beneficial effects:
- Vitamin D synthesis, essential for bone capital (about 15 minutes of exposure of the hands, forearms and face is usually enough — ask your doctor for personalized advice).
- Regulation of the internal clock through melatonin, the sleep hormone.
- Stimulation of well-being hormones (dopamine and serotonin).
- Improvement of some skin conditions such as psoriasis or vitiligo.
But its harmful effects outweigh these: sunburn and burns, sunstroke, premature skin aging, hyperpigmentation, skin cancers (melanoma, carcinoma).
So it’s essential to adopt the right habits: favor shade and go out in the morning or late in the day; wear loose, covering clothing, sunglasses and a wide-brimmed hat; reapply sunscreen at least every 2 hours, and after every swim or physical activity.
How to choose the best sunscreen?
The SPF index, a guarantee of effectiveness. The best protection is stable and broad-spectrum (UVA and UVB), with an SPF measured by an independent laboratory. An SPF 20 lets 5% of UVB through (retains 95%), an SPF 50 lets 2% through (retains 98%). Each index also guarantees UVA protection equal to at least a third of the UVB protection. No product filters UV 100%: there is no such thing as a “total” screen.
Filters: impact on health and the environment. There are two categories: chemical (“organic”) and physical (“mineral”). Chemical filters are synthetic molecules derived from petrochemicals that penetrate the epidermis (active 20 to 30 minutes after application). Some, like oxybenzone (benzophenone-3) or octinoxate, are suspected of being endocrine disruptors, even carcinogens, and are harmful to coral reefs. Nearly 14,000 tons of sunscreen end up in the oceans each year; Hawaii banned the sale of sunscreens containing oxybenzone or octinoxate as of January 1, 2021.
Physical filters (zinc oxide and titanium dioxide) are inert mineral powders that reflect UV like a mirror and act immediately. They are the only ones allowed in certified-organic sunscreens. Well tolerated, they are sometimes found in nanoparticle form for a light, transparent texture; as a precaution, it’s best to avoid the [nano] mention in the ingredient list.
The INCI list, to read closely. Other problematic ingredients are often found in sunscreens (preservatives, stabilizers, fragrances, mineral oils, silicones…). Always analyze the INCI list, which is mandatory on the product.
You now have everything you need to make a well-informed choice and enjoy summer with complete peace of mind!