Is this proof that blue light damages the substantia nigra?

[Reetpetitio]

Hi, I just stumbled across this - looks to my non-science brain like evidence that blue light damages the substantia nigra, and I share it as encouragement to those of you who don't have blue-light blocking glasses for sunset onwards. I love mine! (I have an orange lens for TV viewing and a red pair for when I don't need to be able to see colours accurately. I also use blue light filters on my computer and phone).

ncbi.nlm.nih.gov/pmc/articl...

[Beanie57]

Interesting but does not relate to my PWP... rarely used computer or phone.

[Reetpetitio in reply to Beanie57]

Blue light comes from all lightbulbs and artificial light; it switches off melatonin production which is an essential hormone for not only sleep but also fighting cancer, and is often supplemented for PD too

[gomelgo]

Light pollution is a very real and insidious threat to the health of all life. There is an entire movement of dark sky communities happening. en.wikipedia.org/wiki/Inter... It's not just your computer and phone. We live in a very unnatural world.

[Esperanto]

The map of the US that is supposed to demonstrate the relationship between light pollution and Parkinson's does not seem to apply to Los Angeles and Philadelphia.... It appears to be more related to the lifestyle in certain urban areas.

From the research, it is also unclear to me whether the influence on sleep patterns that you mentioned has been taken into account. In my opinion, blue light is particularly indirectly harmful because it disrupts the circadian rhythm and leads to insufficient sleep. From my own experience, I have noticed that a lack of sleep is detrimental to PD symptoms and may even be a contributing factor to the development of PD.

[Reetpetitio in reply to Esperanto]

I completely agree. Lack of sleep and lack of good quality sleep is clearly linked to dementia and I would be very suprised if it wasn't linked to PD too; I think the disruption of circadian rhythms through blue light exposure at the wrong times of day is going to be key here.

[MarionP]

Well it's a good start, this is an intriguingly creative and fascinating study, these are very bright researchers indeed. One of the things I most enjoyed was that they obviously sat around critiquing their own results and looking for responses to their own self critiques. That is the telltale work of extremely mature and rational scientists practicing of really complete scientific method and it's really refreshing to see.

Results are preliminary but also very very intriguing. As they stated, preliminary plus a great deal of work lies ahead to sort out the pieces that could provide confounding variation to their larger null hypothesis. That said, it is really good study and an excellent start, start of a very long line of work to come but really interesting really intriguing really fun. I wish I were younger and working with for these folks, they are good.

A very good catch indeed, Reetpetitio!

[OKWY]

There may be other benefits of blocking blue light from screens (sleep), but this article actually mentions the two "peak" offenders, 437 nm (violet) and 740 nm (red) light. The reason given was that those two lights penetrated deeper and reacted with Fe+ to oxidise.

[Reetpetitio in reply to OKWY]

Oh how interesting, thank you for picking up on that. A little confusing when red light is said to help PD!

[PDGal4]

Totally unscientific person here, but did note this study is from 2013. Has nothing subsequent been done?

I have read various things on light therapy for Parkinson's, some which say blue light may be effective. I can't get my unscientific brain through this, but would welcome those of you who can to comment or explain. This is from 2022: "Efficacy and Safety of Light Therapy as a Home Treatment for Motor and Non-Motor Symptoms of Parkinson Disease: A Meta-Analysis" ncbi.nlm.nih.gov/pmc/articl...

[Reetpetitio in reply to PDGal4]

Really interesting meta-analysis, thank you. (Not just on blue light though - 'Participants in the 3 studies were exposed to white or polychromatic light with various intensities (from 3000 to 10 000 lux. The other 2 were exposed to blue/green light (450–570 nm).') My read of it is that light therapy was helpful in many areas for PD people, from depression to motor symptoms.

Re my post - It's not that light or blue light is bad - its that we're getting it in a way that disorders our circadian rhythms, which promotes a breakdown of the biology. Light therapy in the morning (sunshine / light box / sitting outside or by a bright window for 10-30 mins) is tremendously helpful for re-setting this, and, I learn from your link, in supporting dopamine production. Really appreciate you posting this. I am a terrible night owl and this is motivating! I tend to focus on trying to get to bed early rather than focusing on getting early morning light - even though I know from Dr Michael Mosley how powerful it is.

[MBAnderson]

"Abstract

Background. Blue light glasses have been introduced as a possible new treatment option to treat sleep disturbances in patients with Parkinson disease (PD). "

"Results. 74% of respondents reported subjective improvements in night-time sleep, daytime sleepiness, depressive symptoms, motor functioning, or a combination thereof. "

hindawi.com/journals/pd/201...

[Reetpetitio in reply to MBAnderson]

Thanks for digging that out. I appreciate that blue light can't be damaging in itself, more, that it's having it at times that dysregulate our circadian rhythm that can profoundly dysregulate the body. That seems to be the purpose of the glasses in the study you posted - a simpler alternative to a light box in the morning for some (or to the obvious: go and sit outside for ten minutes). The study read curiously as it talked about wearing them in the evenings, however, looking up the brand they used the instructions are actually to switch to the *amber* light in the evening - eg to make them blue light *blocking* glasses (although amber is only a partial filter; red being the full filter).

I really noticed the difference at Christmas when I stopped using my blue light filtering glasses because of relatives staying, and upped my normally very dim lighting. It suddenly became much harder to fall asleep, and my mild tremors are worse (although that may also be from a sugary diet over Christmas).

Here they are, for anyone interested in their impressive results from an admittedly low quality trial:

amazon.co.uk/Alaska-Norther...

It encourages me again to focus more in the other end of the day: actually getting bright light into my eyes in the morning, by hook or by crook! Still think getting outdoors is the best...

[MBAnderson in reply to Reetpetitio]

Thanks. Astute. I agree and will continue to wear blue blockers before bed.