Sleeping too much could cause you to go blind, eye doctors have warned.
Hitting the snooze button too often could damage your eyesight as research has revealed that getting more than eight hours a night can lead to macular degeneration – the leading cause for blindness in the UK.
Those who sleep in longer are also seven times more likely to suffer from geographic atrophy, the advanced stages of the condition.
Age-related macular degeneration (AMD) is a disease that gradually destroys sharp, central vision. It’s the leading cause of severe vision loss in people over age 60 .
While there’s no pain, it sees a deterioration of the macula – the part of the eye that allows you to see fine detail – makes driving and reading near impossible.
Research by doctor Rahul N. Khurana, of the Northern California Retina Vitreous Associates, assessed patients with and without the disease.
Dr Khurana surveyed 1003 patients and assessed their sleep patterns, publishing his findings in the journal Retina.
He said: “The mean sleep duration for patients without AMD was 7.97 hours, compared with 8.17 hours, 9.00 hours, and 8.97 hours, respectively, for those with early AMD, neovascular AMD, and geographic atrophy.
“The altered sleep patterns illustrate another morbidity that patients with AMD suffer from, and merit further investigation.”
These findings come after scientists found that sleeping face down on your pillow could also lead to sight loss.
Pressing your face into a pillow while you sleep could cause a condition called glaucoma, which worryingly goes undiagnosed in thousands of people every year.
Glaucoma occurs when a fluid in the eye called aqueous humour fails to drain properly, putting pressure on the optic nerve which can cause the nerve fibres inside to die off and lead to sight loss.
It found sleeping with one side of the face and one eye pressed into a pillow can cause ‘sustained deformation’ of that eye in patients with glaucoma.
Lead researcher Dr. Alison Flatau said that deformation of the eye while sleeping might block outflow of aqueous humour which in turns leads to elevated intraocular pressure (IOP).
She added: “If stress and strain from elevated IOP are bad for eyes with glaucoma, stress and strain from being compressed by a pillow might also be bad for eyes with glaucoma.
Read more: “Carbohydrates could cause lung cancer” scientists name white bread and pasta as no-nos
“On average, glaucoma eye responses did not fully return to baseline levels after moving from face down to supine, but control eyes did.”
Dr Flatau also added that those with ‘prominent’ noses or cheekbones, which prevent direct contact with a pillow, might prevent sleep position-induced deformation of the eye, while those with small cheekbones and a tiny nose are more likely to suffer.
Laser eye surgeon Dr Allamby, founder and medical director or Focus Clinic, said: “Glaucoma is a silent killer when it comes to the eyes.
“Sufferers often don’t know they have it until they’re already losing their vision.
“And what this study shows is that people could be making the condition worse – effectively speeding up the damage – by simply sleeping in the wrong position.
“This slight increase of pressure on the optic nerve could have significant repercussions in those susceptible to nerve damage.”
Early diagnosis of glaucoma is vital in saving a patient’s vision, whether treatment is through eye drops, laser treatment or surgery.
Dr Allamby recommends regular, in-depth eye examinations by an optometrist at least once every two years for those in their 40s.