Is blue light actually bad for the eyes?

Medically Reviewed by Dr. Varshini Shanker, MS | Shroff Eye centre

 

Blue light is part of the visible light spectrum and comes mainly from sunlight, with smaller amounts from LED bulbs, phones, and laptop screens. Too much screen time does cause real eye problems. But the idea that blue light from your phone is silently destroying your vision? That part is not well supported by evidence. Here is what we actually know.

We are going to dispel some popular opinions which aren’t grounded in evidence.

Yes and no. Too much screen time is a definite problem for the eyes. But contrary to popular belief, blue light from screens isn’t as evil as it’s made out to be.

What Is Blue Light?

It’s just a colour in the visible light spectrum of light ( remember VIBGYOR rainbow colours?). There are many colours involved but blue light has an important role to play in the animal and plant kingdoms. The main source of blue light is the Sunlight.
Other smaller sources are televisions, fluorescent and LED light bulbs, smartphones, tablets and laptops.

Too much exposure to blue light can cause blurry vision, eyestrain, macular degeneration, and cataracts.
But there’s a catch! Read on.

How is blue light harmful to the eyes?

• Causes Eye strain & Dry Eye:

Your screen time is important here.The more you stare at that screen, the more likely that you have Dry eye. This basically means your eyes aren’t moist enough- either due to excessive evaporation of tears or because of incomplete blinking. But this is more from staring at screens, not the blue light alone.

• Macular degeneration:

Too much blue light can damage light-sensitive cells in the retina. This can cause macular degeneration later in life and in turn, also lead to permanent vision loss. It’s important to remember that the blue light studied in macular degeneration is from the Sun and the contribution from devices is still debated.

• Post cataract surgery:

If you have cataract or if you’re about to get cataract surgery, ask your surgeon about the type of IOL used to replace your cloudy natural lens.

Is All Blue Light Harmful?

No. Blue light is not inherently bad for you.

Light therapy has been used to treat seasonal affective disorder, a type of depression which is usually caused by lack of sunlight seasonally.

Too much blue light at night can cause sleepless nights & daytime fatigue. Whereas, in the daytime, it may help in setting their circadian rhythm, which is the body’s natural wakefulness and sleep cycle.

So blue light filters won’t save my eyes?
Just using blue light filters without altering other risk factors- such as excess screen use in Dry Eye or Eye strain– are unlikely to help. Read below!

What’s the Deal With Blue Light Filters?

The use of blue light filters, blue light filtering lenses and coatings on specs is on the rise although there is no clinically proven benefit of using these glasses for screen time only.
People who are outdoors a lot should consider investing in a pair of good quality sunglasses to reduce UV light exposure. Excessive exposure to Sunlight has a definite role in Age-related Macular Degeneration ( AMD) & cataract.

Turning on the blue light filters in your devices makes it a little more comfortable to view and may mess your circadian rhythm a bit less- although scientists aren’t yet sure if this will actually save your eyes from damage.

In short, cut out excess screen time and invest in a good pair of sunglasses!

What Should You Actually Do?

• Cut down on screen time, especially in the last hour before bed.
• Use the 20-20-20 rule: every 20 minutes, look at something 20 feet away for 20 seconds.
•  Get a decent pair of UV-filtering sunglasses if you spend time outdoors.
•  If you have persistent dry eye, strain, or blurred vision, see an ophthalmologist rather than assuming blue light glasses will fix it.

At Shroff Eye Centre, we see a lot of patients in Delhi NCR who come in with screen-related dry eye and strain. If symptoms are not improving with basic changes, a proper eye evaluation can help figure out what is actually going on.

 

Frequently Asked Questions

 

Q: Does blue light from screens cause eye damage?

No research does not support that. Most blue light that causes retinal damage comes from the sun, not screens. Screen use can cause eye strain and dry eyes. It’s not the blue light.

Q: Do blue light blocking glasses actually work?

Not in the way most people think. There’s no proof they reduce eye strain from screens. Taking breaks and reducing screen time are options.

Q: Is light from the sun worse than from screens?

Yes it is much worse. Sunlight has blue light more than any screen. Much sun exposure can cause cataracts and AMD. Good sunglasses can help.

Q: Can blue light affect sleep?

Yes it can. Blue light in the evening makes it hard to fall asleep. Avoid screens for an hour before bed, most sleep experts say.

Q: When should I see an eye doctor about screen-related eye problems?

If you still have eye strain, dryness or blurred vision even when you cut down on screen time get it checked. These symptoms can mean you have a problem, like eye disease that needs treatment.