After the wettest April to June on record, you might think that any talk of sunglasses is a bit rose tinted. But in overcast Britain, cycling shades aren't worn primarily to block out ultraviolet rays, nor even to look cool in like a pair of aviators. They're worn to keep stuff out of your eyes, like wind, flies, and dirt. A fly in the eye at speed can make you lose control, while the wind in your face from riding quickly will make your eyes tearful – and your nose run.

In overcast Britain, cycling shades aren't worn primarily to block out ultraviolet rays, nor to look cool in a pair of aviators. 

Why You Should Wear Cycling Glasses

Cycling glasses are essential for keeping things out of your eyes - like wind, flies, and dirt. A fly in the eye at speed can make you lose control, while the wind in your face from riding quickly will make your eyes tearful – and your nose run.

How to Choose Cycling Sunglasses

If you want cycling glasses that also protect your eyes from sunlight, then look for the CE mark. This shows that it meets the the EN1836 standard for blocking harmful radiation, on a scale from 0 to 7: 'insufficient' to '95% blocked'.

UV protection is not dictated by the lens colour, although darker lenses will cut out more visible light. That's helpful in bright light but can compromise your vision in overcast or evening conditions. Yellow and orange are more useful colours than dark grey or brown for cycling, as you'll be able to use them year round.

Photo-chromic lenses darken or lighten according to light conditions. Be aware that they may not lighten quickly enough if you ride out of bright sunlight into the shade beneath trees or a bridge. Some glasses have swappable lenses instead, so you can select from, say, clear, yellow or smoke before you set out.

If your wear prescription glasses, you can of course cycle in those. They won't block wind or bright light as effectively, as they'll have less wraparound and probably no tint. If you cycle in rain, drops on a prescription lens will distort your vision. You could wear contact lenses and cycling glasses; cycling glasses that accept a clip-in prescription lens; or – most convenient but most expensive – prescription cycling glasses.

Finding Cycling Glasses that Fit

Whether you're using £200 prescription glasses or £15 eye-shields, your eyewear needs to fit your head properly so it's comfortable and won't fall off mid-ride. Try for fit – and style - in a bike shop. Cycling-specific glasses often have adjustable nose-pieces, coated so they won't slip off when you sweat. Frames will have grippers on the arms to stay snug on the side of your head.

Cheap eyewear doesn't need to be especially durable as you can just replace it. More expensive cycling eyewear benefits from tough, scratch-resistant lenses and frames that won't snap if you sit or tread on the glasses.

Glasses seldom fall off while commuting by bike. If you have a bumpy ride to work and this is an issue, a retainer will stop them bouncing away underneath a bus. Either make something or invest in one from Croakies (www.croakies.com). Glasses can fog up in rain, or from your breath when you stop at the lights, so anti-fog coatings and vents are useful. You can also polish them with washing-up liquid or apply motorcyclists' visor spray.

Cycling glasses can be very expensive but unless they have prescription lenses they needn't be – as these ones show.