Un guide des lunettes de soleil avec protection UV

Sunglasses - why is UV protection important?

Ce n'est pas seulement notre peau que les rayons ultraviolets (UV) peuvent endommager. Une exposition prolongée aux rayons UV dans sunlight peut endommager les structures à l'intérieur de nos yeux, ainsi que la peau autour. Les experts estiment que nos yeux sont 10 fois plus sensibles à la lumière UV que our skin¹.

Bhavin Shah, behavioural optometrist at Central Vision Opticians, says that protecting our eyes is essential: "this is especially true for long-term exposure and for young people. It's thought that up to 80% of a person's exposure to sunlight occurs before the age of 18."

What do the different UV categories mean?

UV light is made up of UVA and UVB radiation - invisible rays of light projected from the sun.

• UVA radiation - pénètre plus profondément dans l'œil, pouvant potentiellement endommager le cristallin et la rétine derrière l'iris (la partie colorée) et la pupille (la partie noire). Cela peut causer des problèmes oculaires, endommager la vision et accélérer le vieillissement.

• UVB radiation - est absorbé par la surface de la cornée, la couche externe transparente de l'œil qui recouvre l'iris et la pupille. Une exposition répétée peut causer des dommages permanents à la cornée.

Benefits of sunglasses

By purchasing UV protection sunglasses that meet the health standards of protection, you can:

Protect your eyesight

Selon le Dr Robbie Walker, ophtalmologiste consultant, une exposition prolongée au soleil peut accélérer une chirurgie de la cataracte formation. "C'est lorsque le cristallin naturel à l'intérieur de votre œil devient trouble et réduit votre vision. Les cataractes sont normalement associées au vieillissement."

One study found that not wearing sunglasses, or using other protective measures like broad-rimmed hats, increased the risk of cataracts by up to 70%².

"Nous pensons également que la lumière du soleil peut aggraver age-related macular degeneration (AMD) chez les personnes susceptibles à cette condition," dit Walker. Cette affection oculaire est causée par la dégradation de la rétine - une partie à l'arrière de l'œil responsable de la vision nette et des détails. Bien que liée à l'âge, passer régulièrement jusqu'à huit heures au soleil sans protection oculaire signifie que vous êtes beaucoup plus susceptible de développer la DMLA beaucoup plus jeune³.

Prevent growths

Not wearing UV protection sunglasses can also increase the risk of growths on the skin around the eye.

Reduce short-term sun damage

Tout comme la peau, nos yeux sont également vulnérables aux symptômes temporaires et inconfortables de la surexposition. L'optométriste Shah déclare : "la surexposition à la lumière UV - et surtout à la lumière réfléchie qui peut se produire lors du ski ou de la pratique de sports nautiques - peut causer des dommages à court terme à la surface avant de l'œil, similaires à un coup de soleil."

This sunburn-like condition is called photokeratitis, and often involves painful, swollen, red, and watery eyes that can last around one or two days. In severe cases, it can cause temporary loss of vision - but this damage isn't permanent.

Avoid eye strain

Porter des lunettes de soleil teintées foncées peut également protéger vos yeux de la lumière visible, ce qui réduit le strain vous mettez sur vos yeux lorsque vous plissez les yeux pour voir sous un soleil éclatant. Si vous êtes enclin à headaches and migraines, this may help.

However, don't assume that all dark-tinted lenses offer UV protection - in fact, very dark lenses typically offer no UV protection at all.

What to look for when choosing sunglasses

How can I tell if my sunglasses have UV protection?

Lorsqu'il s'agit d'acheter des lunettes de soleil, la protection UV est le facteur le plus important. Vos lunettes doivent bloquer suffisamment les rayons UVA et UVB, tout comme SPF for sunscreen, there are standards to look out for:

Blue light and spectral filters

Les experts estiment qu'il pourrait également y avoir des avantages dans les lunettes de soleil avec protection UV qui ont également blue light blocking filters - une forme de rayonnement visible et à haute énergie - mais Shah explique que les preuves sont mitigées.

"A blue light filter is not specifically required when buying sunglasses, but some manufacturers make sunglasses which block more of the blue end of the light spectrum because this may help to reduce glare and eye strain.

"While blue light may damage the cells in the retina and help to reduce overstimulation when using digital devices, the evidence is contradictory and inconclusive."

Instead, the optometrist recommends a spectral filter which blocks more than the blue end of the spectrum of light. "This makes them comfortable to wear when driving in overcast weather," he adds.

Anti-glare, polarised, and anti-reflection

You may find that different UV protection sunglasses also claim to be anti-glare, polarised, or anti-reflective. Shah breaks down what these terms mean, and how important they are.

"If you're going to be out on the ski slopes, above water while fishing or sailing, or driving on a wet surface, then a pair of UV protection sunglasses with polarised lenses will be best.

"Anti-glare, polarised lenses, and anti-reflective lenses mean slightly different things. All sunglasses will reduce glare to some extent, and anti-reflective surfaces minimise some glare from the back surface of the lenses. Polarising sunglasses reduce glare specifically from reflected sunlight, such as from snow, water, or a wet road surface. These tend to be better for reducing glare and are usually darker than non-polarised lenses.

"The downside of polarised lenses is that when viewing some screens - such as phones or display panels in cars - they may filter and reduce the image quality. Pilots can't use polarised sunglasses because they hinder their ability to see the instrument panel in modern planes."

Size, style and position

For the ultimate protection, you'll also want to consider how your UV protection sunglasses fit around your eyes. UV rays don't do all their damage head on - they can also be scattered and reflected so that they enter your eyes from the above, below, and the sides of your glasses. This means that:

• Small sunglasses are more likely to let UV light reach your eyes from the side.

• Sunglasses that sit 6 mm or more away from your forehead increases the amount of UV exposure by up to 20%⁴.

• Therefore, wrap-around and tight-fitting designs and side shields offer more protection.

• This is especially important if you’re around light reflective surfaces such as snow, water, and sand.

Pour en savoir plus

1. Nielson Eyecare: Are eyes sensitive to UV damage?

2. Chen et al: Relationship between practices of eye protection against solar ultraviolet radiation and cataract in a rural area.

3. Shick et al: History of sunlight exposure is a risk factor for age-related macular degeneration.

4. Izadi et al: Photokeratitis induced by ultraviolet radiation in travelers: A major health problem.

5. Bazzazi et al: Quality of sunglasses available in the Iranian market; a study with emphasis on sellers' license.