Nisha Pandey

Can’t Sleep In A Completely Dark Bedroom? Study Says Even Dim Light May Affect Your Heart

Not all of us are able to drift off soundly in a completely blacked-out bedroom. So, if you need a little light to fall asleep, you may need to reconsider the habit as a new study suggests that it could be harmful for your heart. 

The study does not recommend a minimum amount of light that could be suitable for sleeping and indirectly <span>heart health</span>. It says that even the dimmest light may not work in your favour. 

Researchers have found that people exposed to higher levels of light while sleeping showed changes in the structure and function of their hearts several years later. The findings has therefore raised concerns that nighttime light exposure may be another cardiovascular risk factor that could be modifiable. 

The research, led by Professor <span>Lu Qi</span> of <span>Tulane University</span>, involved more than 11,000 UK adults. Participants wore light sensors on their wrists for a week, allowing researchers to estimate how much light they were exposed to during <a href="https://www.healthandme.com/health-news/melatonin-or-insomnia-scientists-question-90-higher-heart-failure-risk-linked-to-long-term-use-of-the-supplement-article-156014590" data-type="tilCustomLink">nighttime sleep</a>. 

Around three years later, participants underwent cardiac MRI scans. Researchers then compared their heart structure and function with their previous nighttime light exposure. 

People exposed to 3 lux or more of light during <span>sleep</span> showed greater changes in their hearts compared with those sleeping in darker environments. 

These included thickening of the wall of the left ventricle, the <a href="https://www.healthandme.com/health-news/melatonin-or-insomnia-scientists-question-90-higher-heart-failure-risk-linked-to-long-term-use-of-the-supplement-article-156014590" data-type="tilCustomLink">heart's </a> main pumping chamber. The researchers also observed early signs of impaired heart function and changes involving the right ventricle and left atrium.

Also read: <a href="https://www.healthandme.com/health-wellness/are-glp-1-drugs-actually-changing-asthma-biology-or-are-people-simply-having-fewer-attacks-due-to-weight-loss-article-156127862" data-type="tilCustomLink">Are GLP-1 Drugs Actually Changing Asthma Biology, Or Are People Simply Having Fewer Attack Due To Weight Loss?</a> 

<h2>'<span rel="noindex">Cardiac Remodelling</span>' </h2>

The changes identified by researchers fall under the term called '<a href="https://www.healthandme.com/health-news/heart-disease-can-damage-your-kidneys-and-vice-versa-new-guidelines-explain-why-article-156097624" data-type="tilCustomLink">cardiac remodelling</a>'. Professor Qi explained that cardiac remodelling typically occurs when the heart biologically adapts to chronic stress or injury. 

Over time, these structural changes can affect how efficiently the heart pumps blood and may contribute to heart failure. 

“Light pollution has emerged as a new risk factor for <span>cardiovascular disease</span>,” Qi said, adding that reducing nighttime light exposure could become one strategy for preventing cardiovascular disease. 

But this does not mean that every person who sleeps with a light on is damaging their heart. The study was observational, meaning researchers could identify a relationship but could not establish that light itself caused the cardiac changes.

Also read: <a href="https://www.healthandme.com/health-news/this-common-heart-attack-risk-starts-silently-in-healthy-people-in-their-20s-article-156106159" data-type="tilCustomLink">This Common Heart Attack Risk Starts Silently In Healthy People In Their 20s</a> 

<h2>How Could Nighttime Light Exposure Affect Heart? </h2>

Heart Attack at 28? Heart Screening, Chest Pain & ECG Explained | Healthy & Hearty Picks

A possible explanation that could explain the association between heart and nighttime light exposure is is the body's <a href="https://www.healthandme.com/health-wellness/ever-wonder-why-you-keep-scrolling-short-videos-your-brain-may-be-switching-off-self-control-article-155781502" data-type="tilCustomLink">circadian rhythm</a>. It is our internal 24-hour clock that regulates sleep, hormones and other physiological processes. 

Light at night can signal the brain that it is still daytime, which could interfere with melatonin production and normal sleep-wake regulation. Poor or disrupted sleep can, in turn, affect multiple processes connected to <span>cardiovascular health</span>, including blood pressure and metabolism. 

Previous research has also linked greater nighttime light exposure with higher risks of cardiovascular disease. 

<h2>How Dark Should Your Bedroom Be? </h2>

The researchers and an accompanying editorial suggest reducing unnecessary light exposure during sleep. 

Simple measures include using blackout curtains, covering bright electronic LEDs and avoiding unnecessary screens or strong lighting close to bedtime. The editorial also recommends warmer-coloured bedside lighting if illumination is necessary.

Health Conditions A-Z

health

cant-sleep-in-a-completely-dark-bedroom-study-says-even-dim-light-may-affect-your-heart

sleep

bedroom light

heart damage

cardiovascular health

lu qi

cardiac remodelling

Tulane University

heart health

cardiovascular disease

cardiovascular disease prevention

world-suicide-prevention-day-2026-why-women-still-face-mental-health-barriers

World Suicide Prevention Day 2026: Why Women Still Face Mental Health Barriers

synthetic-paneer-whitened-with-chuna-busted-in-delhi-how-dangerous-is-it-for-your-health

Synthetic Paneer Whitened With Chuna Busted In Delhi: How Dangerous Is It For Your Health?

Health & Wellness

8 Sit-Up Variations to Strengthen Your Core and Build Stability

Benefits Of Ayurvedic Health Supplement Ashwagandha

9 Anti-Inflammatory Breakfast Options You Should Try

5 Foods You Should Avoid For PCOS, Says Gynecologist

Love Sitting With Your Legs Crossed? Here’s You Should Avoid It

6 Daily Foods That Are Secretly Increasing Your Calories

9 Brain Boosters You Should Do Everyday

Hip Exercises That Will Keep You Flexible As You Age

9 Leg Exercises Office Workers’ Should Do At Home

Benefits of Having Herbal Tea Every Morning

9 Daily Habits That Boost Your Brain Power

Lower-Body Exercises That Are Game-Changers

How Drinking Apple Cider Vinegar Helps You

Aging Myths You Should Never Believe

Superfoods That Support Your Gut Health

What Happens To Your Body When You Eat Instant Noodles Every Day?

Health Issues Premature Babies Often Face

Exercises Office Workers Should Do For Their Heart Health

Reasons Why You Should Add Raw Turmeric To Your Diet

Benefits Of Drinking Milk At Night: Why You Should Do It

Food That Provides Vitamin B12 Naturally In Your Diet

Surprising Health Benefits Of Fenugreek Seeds

9 Superfoods You Should Eat For Your Brain Health

What Does Mental Health Support Look Like At Work?

Long Stretches You Should Do To Unwind From Your Day

Colon Cancer In Young Adults: Early Symptoms You Should Know

Health Benefits Of Eating Dry Fruits Everyday

Are You At Risk For Fried Rice Syndrome?

These Tests Reveal How Well You Are Aging

Lower-Back Exercises You Should Do After A Long-Day's Work

Children’s Diet – What Kids Need To Eat For Immunity Building

Common Diabetes Myths That Could Hurt Your Health

Love Spicy Food? Here’s How It Affects Your Health

Superfood List: Veggies And Fruits You Must Have For Immunity

Foods People With IBS Should Avoid

Exercises To Improve Digestion

Easy Work Lunches You Can Make In The Morning

Hunger Vs Craving: Difference Explained In 60 seconds

These Things Can Cause Your Heart To Age Faster

High Carb Foods That Are Actually Healthy

Not all of us are able to drift off soundly in a completely blacked-out bedroom. So, if you need a little light to fall asleep, you may need to reconsider the habit as a new study suggests that it could be harmful for your heart. The study does not recommend a minimum amount of light that could be suitable for sleeping and indirectly heart health. It says that even the dimmest light may not work in your favour. Researchers have found that people exposed to higher levels of light while sleeping showed changes in the structure and function of their hearts several years later. The findings has therefore raised concerns that nighttime light exposure may be another cardiovascular risk factor that could be modifiable. More About The Study The research, led by Professor Lu Qi of Tulane University, involved more than 11,000 UK adults. Participants wore light sensors on their wrists for a week, allowing researchers to estimate how much light they were exposed to during nighttime sleep. Around three years later, participants underwent cardiac MRI scans. Researchers then compared their heart structure and function with their previous nighttime light exposure. People exposed to 3 lux or more of light during sleep showed greater changes in their hearts compared with those sleeping in darker environments. These included thickening of the wall of the left ventricle, the heart's  main pumping chamber. The researchers also observed early signs of impaired heart function and changes involving the right ventricle and left atrium.Also read: Are GLP-1 Drugs Actually Changing Asthma Biology, Or Are People Simply Having Fewer Attack Due To Weight Loss? 'Cardiac Remodelling' The changes identified by researchers fall under the term called 'cardiac remodelling'. Professor Qi explained that cardiac remodelling typically occurs when the heart biologically adapts to chronic stress or injury. Over time, these structural changes can affect how efficiently the heart pumps blood and may contribute to heart failure. “Light pollution has emerged as a new risk factor for cardiovascular disease,” Qi said, adding that reducing nighttime light exposure could become one strategy for preventing cardiovascular disease. But this does not mean that every person who sleeps with a light on is damaging their heart. The study was observational, meaning researchers could identify a relationship but could not establish that light itself caused the cardiac changes.Also read: This Common Heart Attack Risk Starts Silently In Healthy People In Their 20s How Could Nighttime Light Exposure Affect Heart?                   A possible explanation that could explain the association between heart and nighttime light exposure is is the body's circadian rhythm. It is our internal 24-hour clock that regulates sleep, hormones and other physiological processes. Light at night can signal the brain that it is still daytime, which could interfere with melatonin production and normal sleep-wake regulation. Poor or disrupted sleep can, in turn, affect multiple processes connected to cardiovascular health, including blood pressure and metabolism. Previous research has also linked greater nighttime light exposure with higher risks of cardiovascular disease. How Dark Should Your Bedroom Be? The researchers and an accompanying editorial suggest reducing unnecessary light exposure during sleep. Simple measures include using blackout curtains, covering bright electronic LEDs and avoiding unnecessary screens or strong lighting close to bedtime. The editorial also recommends warmer-coloured bedside lighting if illumination is necessary.

can’t sleep in a completely dark bedroom? study says even dim light may affect your heart

About Us

Contact Us

Terms & Conditions

Privacy Policy

Company

Health and Me is a premium website with content written and curated to function as a handbook for all Health concerns.

Can’t Sleep In A Completely Dark Bedroom? Study Says Even Dim Light May Affect Your Heart

World Suicide Prevention Day 2026: Why Women Still Face Mental Health Barriers

Suicide Prevention Day: When Does A Distressing Thought Become A Suicide Warning Sign? Expert Explain

Are GLP-1 Drugs Actually Changing Asthma Biology, Or Are People Simply Having Fewer Attack Due To Weight Loss?

Health Conditions A-Z

Can’t Sleep In A Completely Dark Bedroom? Study Says Even Dim Light May Affect Your Heart

World Suicide Prevention Day 2026: Why Women Still Face Mental Health Barriers

Synthetic Paneer Whitened With Chuna Busted In Delhi: How Dangerous Is It For Your Health?