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Why do my eyes squint in the sun?

And other reasons you may be squinting



Direct sunlight can make you squint because the natural reflex action reduces the amount of light that reaches your eyes. When this happens, the muscles that control your eyelids contract, which helps you to protect your eyes from all types of light. When you squint your eyes, your pupils narrow to about a millimetre, which allows less light to enter your eyes and be absorbed by your retina.


How can I stop my eyes from squinting in the sun?


The first action you should take to help with your eye’s sensitivity to light is to invest in some good quality sunglasses. Sunglasses are considered protective eyewear because they filter out UV rays. Scientists have found that wearing sunglasses can reduce the risk of cataracts.


When choosing sunglasses, look for the following:

  • 100 per cent UV blocking

  • Polarised lenses reduce glare from water, sand, and snow and can also help make objects look sharper

  • Tinted lenses that can help protect your eyes from UV rays

  • Lenses with a mirror coating can help reduce the amount of light that enters your eyes, and may also prevent reflections from surfaces such as car windshields and windows

  • A wraparound design is great for helping keep the sunlight out of your peripheral vision


Most people’s eyes are very sensitive to bright light, like the intense light from the sun. The UV rays from the sun can cause cataracts when you get older and direct bright sunlight can cause damage to both the retina and cornea; the retina is the part of the eye that senses light and the cornea is the front surface of the eye. Squinting can also occur with sensitivity to bright indoor light as well as sensitivity to sunlight.


Read our blog on UV Eye Damage for more information about UV rays, the damage they can do, and how you can protect your eyes.


What should you do if you’re squinting?


The first thing you should do is make sure your eyes are healthy. Regular eye examinations are important so the Optician can monitor your vision, and offer diagnosis or treatment if necessary. We have easy Online Booking for appointments or call 020 8759 9395. If you find your eyes are healthy following eye exams, then you can look at the following causes of squinting:

  • You’re working on a computer screen and need to take a break to give your eyes a rest

  • You’re outside and the sun’s glare is making it difficult for you to see which can easily be solved with a pair of sunglasses, with or without prescription

  • You’re working for an extended period of time without a break in a poorly lit room with fluorescent lights or outside in the dark with very little light


If you’re squinting in the sun, it is because your eyes don’t have enough protection from the harsh light. Another reason your eyes may be squinting is because of a problem with your vision. You may have astigmatism, or you could have a problem with your cornea. If you have a problem with your cornea, you may have a corneal abrasion, and squinting can help you cope with this problem. UV light can also damage your retina and macula, both of which are linked to developing macular degeneration.


Squinting can also be a sign of a serious medical condition, such as the onset of glaucoma. This is an eye condition in which increased pressure builds up inside the eyes. When light enters the eye, it picks up on the pressure and causes pain. The pain is a warning that your eyes need immediate medical attention, and squinting is one way to deal with the pressure. For example, if you’re out in the sun and experiencing increased light sensitivity because of glaucoma, squinting would help ease some of the discomforts.


Squinting can also be a sign of a problem with your vision. Farsightedness occurs when the eye isn’t strong enough to properly focus light on your retina. The light can’t focus correctly, causing you to squint. Shortsightedness, on the other hand, is where the eye is too strong and light is focused in front of the retina. This causes you to squint because you’re trying to see properly.


Our advice for an eye injury or emergency


Eye conditions can happen to anyone, at any time. It doesn't matter how young or old you are, or how to fit you are. It's our goal to help you get back to your normal life as quickly as possible. If you are ever worried about your eyes or your family’s eye health, feel free to come and talk to us about eye care. We may be able to help you with a simple course of eye drops. Call 020 8759 9395 to make an appointment for an eye test. Alternatively, you can book online.

Find us at 742 Bath Road, Cranford, Hounslow, London, TW5 9TY. Street parking on The Avenue, High Street, Berkeley Avenue or Waye Avenue. Car parks available at the Ibis Budget London Heathrow Central (TW5 9SX) and DoubleTree Hilton by Hilton London Heathrow Airport (TW5 9QE). Please check for parking conditions.


Ideally located near the Heathrow airport in the London Borough of Hounslow, Cranford Opticians can be easily reached from Twickenham, Feltham, Richmond , Teddington, Whitton, Hayes, Heston, Harlington, Southall, Staines, Ashford, Stanwell, Sunbury and many other areas in London and Surrey.


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