In this post:
- Why I wear blue blockers
- Sources of blue light and its affect on melatonin
- Issues with blue light exposure at night including its effects on our metabolism, obesity and insulin resistance.
- 4 Ways to Avoid Blue Light and Boost Metabolism (Research Proves it)
It should come as no surprise to many of you that I am a blue blocker wearing fit chick after the sun sets (and so is my family). Why? Long term health goals of course. Check it out:
- Blue light exposure during the day is crucial but after the sun sets, blue light is crummy for your health.
- Our body’s “internal clock,” aka circadian rhythm is regulated by this blue light (ref 1).
- This circadian rhythm, triggered primarily by the blue spectrum of light (aka the sun), is very important to maintain. It primes our body to be awake, alert, productive and improve performance during the day (ref 3) but sets us up for quality sleep and recovery at night (ref 2). Don’t mess with my gainz!
Quality and quantity of sleep is of the utmost importance and completely underrated in our society. And, the majority of Americans, including our developing children are exposed to electronics into the wee hours of the night.
When it gets dark in the evening, the pineal gland (das in yer brain) secretes the hormone melatonin. This ready’s your bod to get tired and sleep BUT, the exposure to these sources of blue light.…
- Indoor artificial lights
- Digital Screens such as computers, cell phones, laptops & tablets.
- Any electronic device
- Fluorescent light
- LED lighting
…does a great job of shutting down that melatonin production (ref 4, 5). Bad news bears. Check out this study published in The Journal of Clinical Endocrinology & Metabolism (ref 14) that found bright light in the evenings suppressed melatonin to nearly nothing through out the entire night relative to dim light or wearing blue blocking goggles.
Issues with blue light exposure at night
- Our brain thinks is daytime and suppresses melatonin (ref 14).
- Reduction in quality and quantity of sleep.
- Lack of sleep quality is linked to chronic diseases such as heart disease and type II diabetes as well as various health issues including cancer, depression, insulin resistance, metabolic syndrome and obesity! (ref 6, 7,8,9, 12,13)
and there it is…. blue light exposure can affect our metabolism and cause us to maintain a fluffier physique than we really should (ref 9, 10).
Research shows that groups of people exposed to blue light in the evenings had significantly higher glucose levels than those not exposed to blue light in the evenings (ref 12, 13). “Our findings show that insulin was unable to acutely bring glucose levels back to a baseline level following a meal with bright light exposure in the evening,” said one of the researchers, Ivy Cheung.
Although research cannot conclude the exact mechanisms as to why insulin is not regulating blood glucose levels properly when individuals are exposed to blue light at night, many studies are showing us that night time blue light exposure is effing with our system and causing detrimental health outcomes.
Why work so hard during the day to eat healthy and hit the gym if we aren’t going to let our body rest, recover and let our hormones regulate properly. It’s like wasting your time. Follow these simple steps to improve your health!!!
4 Ways to Avoid Blue Light and Boost Metabolism (Research Proves it)
1.) Turn off electronics. Stop rolling your eyes. It can be done and you will survive without facebook. I promise.
2.) Get the TV out of the bedroom! Stop falling asleep with that thing on!
3.) Since you won’t turn off your phone or TV or wander around in the dark for that matter, wear blueblocking glasses like these Uvex glasses or the dashingly stylish Swannies when the sun sets. In the winter that’s like 4 PM, in the summer its more like 9 PM!
4.) Download programs onto your electronics that will automatically reduce blue light emitting from your phone based on the when sun rises and sets. I use twilight for my phone and flux for my computer.
Want to keep tabs on your sleep quality? Check out my FAVORITE fitness tracker. The Oura Ring!
Tracking my sleep quality keeps me motivated to make sure I do what I can to optimize sleep! Enter “HeatherGF2” for a 10% discount. I snapchat it all the time as well: heathergf2
Why did I choose a ring over a bracelet for a fitness tracker? Well, this smart little ring does not emit EMF unless I connect it to the app on my phone and download data. Super important to my health!!
ref 1: Martha Hotz Vitaterna, Ph.D., Joseph S. Takahashi, Ph.D., and Fred W. Turek, Ph.D. Overview of Circadian Rhythms
ref 2: Purves D, Augustine GJ, Fitzpatrick D, et al., editors.The Circadian Cycle of Sleep and Wakefulness. Sunderland (MA): Sinauer Associates; 2001.
ref 3: Münch M1, Linhart F, Borisuit A, Jaeggi SM, Scartezzini JL. Effects of prior light exposure on early evening performance, subjective sleepiness, and hormonal secretion. Behav Neurosci. 2012 Feb;126(1):196-203. doi: 10.1037/a0026702. Epub 2011 Dec 26.
ref 4: Joshua J. Gooley, Kyle Chamberlain, Kurt A. Smith, Sat Bir S. Khalsa, Shantha M. W. Rajaratnam, Eliza Van Reen, Jamie M. Zeitzer, Charles A. Czeisler, and Steven W. Lockley Exposure to Room Light before Bedtime Suppresses Melatonin Onset and Shortens Melatonin Duration in HumansJ Clin Endocrinol Metab. 2011 Mar; 96(3): E463–E472.Published online 2010 Dec 30. doi: 10.1210/jc.2010-2098
ref 5: Figueiro MG1, Wood B, Plitnick B, Rea MS. The impact of light from computer monitors on melatonin levels in college students. Neuro Endocrinol Lett. 2011;32(2):158-63.
ref 6: Francesco P. Cappuccio1*†, Daniel Cooper1, Lanfranco D’Elia2, Pasquale Strazzullo2, and Michelle A. Miller1† Sleep duration predicts cardiovascular outcomes: a systematic review and meta-analysis of prospective studies. European Heart Journal (2011) 32, 1484–1492 doi:10.1093/eurheartj/ehr007
ref 7: Cappuccio FP1, D’Elia L, Strazzullo P, Miller MA. Quantity and quality of sleep and incidence of type 2 diabetes: a systematic review and meta-analysis. Diabetes Care. 2010 Feb;33(2):414-20. doi: 10.2337/dc09-1124. Epub 2009 Nov 12.
ref 8: Alvaro PK1, Roberts RM, Harris JK. A Systematic Review Assessing Bidirectionality between Sleep Disturbances, Anxiety, and Depression. Sleep. 2013 Jul 1;36(7):1059-1068.
ref 9: Francesco P. Cappuccio, MD, FRCP,1 Frances M. Taggart, PhD,1 Ngianga-Bakwin Kandala, PhD,1 Andrew Currie, MB ChB,1 Ed Peile, FRCP,2 Saverio Stranges, MD, PhD,1 and Michelle A. Miller, PhD1.Meta-Analysis of Short Sleep Duration and Obesity in Children and Adults Sleep. 2008 May 1; 31(5): 619–626.
ref 10: Light exposure and kids’ weight: Is there a link?
ref 11: Bright Light Alters Metabolism
ref 12: Kathryn J. Reid ,Giovanni Santostasi ,Kelly G. Baron,John Wilson, Joseph Kang, Phyllis C. Zee.Timing and Intensity of Light Correlate with Body Weight in Adults
ref 13:Ivy N. Cheung,Phyllis C. Zee,Dov Shalman,Roneil G. Malkani,Joseph Kang, Kathryn J. Reid.Morning and Evening Blue-Enriched Light Exposure Alters Metabolic Function in Normal Weight Adults
ref 14:Leonid Kayumov, Robert F. Casper, Raed J. Hawa, Boris Perelman, Sharon A. Chung,Steven Sokalsky, Colin M. Shapiro. (2005) 90 (5): 2755-2761.Published:01 May 2005 Blocking Low-Wavelength Light Prevents Nocturnal Melatonin Suppression with No Adverse Effect on Performance during Simulated Shift Work
Great article. Exposure to light after dark is also associated with obesity, heart disease and cancer… oh my!