# SAD full spectrum lighting **URL:** \ **Category:** Factual Questions\ **Created:** [December 29, 2010, 12:20am UTC](https://boards.straightdope.com/t/sad-full-spectrum-lighting/565665 "2010-12-29T00:20:07Z")\ **Posts on this page:** 11\ **Page:** 1
**Author:** ![jakesteele](https://avatars.discourse-cdn.com/v4/letter/j/ed8c4c/32.png) [@jakesteele](https://boards.straightdope.com/u/jakesteele)\ **Post date:** [December 29, 2010, 12:20am UTC](https://boards.straightdope.com/t/sad-full-spectrum-lighting/565665/1 "2010-12-29T00:20:07Z")
I am looking to buy a SAD light, but before I do, I want to get the scoop on them. Is SAD real and do these type of lights noticeably help? If so, what are some good recommendations? ---
**Author:** ![chacoguy](https://avatars.discourse-cdn.com/v4/letter/c/50afbb/32.png) [@chacoguy](https://boards.straightdope.com/u/chacoguy)\ **Post date:** [December 29, 2010, 1:03am UTC](https://boards.straightdope.com/t/sad-full-spectrum-lighting/565665/2 "2010-12-29T01:03:59Z")
We installed full spectrum lights in my shop to check photographs. Several of my staff mentioned a positive impact. ---
**Author:** ![Rachellelogram](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/rachellelogram/32/8689_2.png) [@Rachellelogram](https://boards.straightdope.com/u/Rachellelogram)\ **Post date:** [December 29, 2010, 3:43am UTC](https://boards.straightdope.com/t/sad-full-spectrum-lighting/565665/3 "2010-12-29T03:43:32Z")
[Yes, SAD is real.](http://en.wikipedia.org/wiki/Seasonal_affective_disorder) I’m sorry I cannot help you with your other questions. ---
**Author:** ![Nicest\_of\_the\_Damned](https://avatars.discourse-cdn.com/v4/letter/n/8baadc/32.png) [@Nicest\_of\_the\_Damned](https://boards.straightdope.com/u/Nicest_of_the_Damned)\ **Post date:** [December 29, 2010, 4:40am UTC](https://boards.straightdope.com/t/sad-full-spectrum-lighting/565665/4 "2010-12-29T04:40:45Z")
I was recently told by a doctor that the SAD lights are not necessary. He said regular bright lights will work. I think he said 200 watts for a couple hours in the morning and evening. Just having them on in the room with you is enough, you don’t have to sit in front of them. You can get full spectrum compact florescent bulbs pretty inexpensively and they are brighter than comparable incandescent bulbs so you can probably get 200 watts of light from a couple of regular desk lamps without exceeding the limits. Not quite an answer to your question but I thought I would throw it in for what it’s worth. ---
**Author:** ![BaneSidhe](https://avatars.discourse-cdn.com/v4/letter/b/c5a1d2/32.png) [@BaneSidhe](https://boards.straightdope.com/u/BaneSidhe)\ **Post date:** [December 29, 2010, 5:41am UTC](https://boards.straightdope.com/t/sad-full-spectrum-lighting/565665/5 "2010-12-29T05:41:49Z")
I have a SAD light and it’s been a wonder these past several winters. Our office lighting is shitty as hell and the light makes things nicer. I noticed within a couple of weeks of use my moods didn’t swing from semi-happy to suicidal as often, and I felt better overall. ---
**Author:** ![Nava](https://avatars.discourse-cdn.com/v4/letter/n/da6949/32.png) [@Nava](https://boards.straightdope.com/u/Nava)\ **Post date:** [December 29, 2010, 11:18am UTC](https://boards.straightdope.com/t/sad-full-spectrum-lighting/565665/6 "2010-12-29T11:18:12Z")
> [@chacoguy](#): > > We installed full spectrum lights in my shop to check photographs. Several of my staff mentioned a positive impact. I found myself in that situation two years ago: I purchased a full-spectrum light for hobby purposes, discovered it wakes me right up when the day’s natural conditions would have led to feeling like a wet rag. **Nicest of the damned** , make up your mind. First you say “SAD lights” are not needed, then you recommend full-spectrum lights - that’s what so-called “SAD lights” are, and it is not the same as “any bright light”. ---
**Author:** ![Francis\_Vaughan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/francis_vaughan/32/3093_2.png) [@Francis\_Vaughan](https://boards.straightdope.com/u/Francis_Vaughan)\ **Post date:** [December 29, 2010, 12:15pm UTC](https://boards.straightdope.com/t/sad-full-spectrum-lighting/565665/7 "2010-12-29T12:15:54Z")
There is a difference between a SAD light and a “full-spectrum” light. For the SADs you simply need bright white light. The effect seems to be more about circardan rhythm than some idea of perfect daylight. Just bright white fluro lights are fine. The “full spectrum” lights are something different - although they seem to be marketed as helping with the SADs. There is no defined meaning to a full-spectrum lamp, it is a marketing term, not a technical one. And there is variation amongst so called full spectrum lamps. Some full spectrum lamps are identical in spectral output to some conventional lamps sold at one third the price. Some full-spectrum lamps have some UV output (which is not a great idea) and claim a positive value in this, others don’t. You can find halogen and florescent full spectrum lights. No matter what you do with a florescent you can’t avoid significant line emission peaks in the spectra. This makes interesting reading. [http://www.lrc.rpi.edu/programs/nlpip/lightinganswers/fullspectrum/abstract.asp](http://www.lrc.rpi.edu/programs/nlpip/lightinganswers/fullspectrum/abstract.asp) ---
**Author:** ![DSeid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dseid/32/20194_2.png) [@DSeid](https://boards.straightdope.com/u/DSeid)\ **Post date:** [December 29, 2010, 1:57pm UTC](https://boards.straightdope.com/t/sad-full-spectrum-lighting/565665/8 "2010-12-29T13:57:01Z")
So agreed by all that [SAD is real and that light therapy helps](http://archpsyc.ama-assn.org/cgi/content/abstract/55/10/883). The issues are what spectrum, what intensity, for how long, and what timing. At least for [acute effects](http://www.pnas.org/content/107/45/19549.abstract) blue is critical, and blue [seems](http://www.ncbi.nlm.nih.gov/pubmed/19016463) more key for treating SAD as well. Intensity seems to be an open question but ranges from 2500 to 10,000 lux recommendations. That’s about what morning outside light on a bright day would give you. Getting that intensity requires staying fairly close to the quite strong light source. That’s what the light boxes offer over changing your indoor bulbs. Most protocols advise 30 minutes of exposure at 10,000 lux and longer with a less intense light source but I can find no data to support one period of time over another. [Early morning](http://archpsyc.ama-assn.org/cgi/content/abstract/58/1/69) seems to be most effective. Good luck. ---
**Author:** ![Nicest\_of\_the\_Damned](https://avatars.discourse-cdn.com/v4/letter/n/8baadc/32.png) [@Nicest\_of\_the\_Damned](https://boards.straightdope.com/u/Nicest_of_the_Damned)\ **Post date:** [December 30, 2010, 11:33pm UTC](https://boards.straightdope.com/t/sad-full-spectrum-lighting/565665/9 "2010-12-30T23:33:56Z")
> [@Nava](#): > > **Nicest of the damned** , make up your mind. First you say “SAD lights” are not needed, then you recommend full-spectrum lights - that’s what so-called “SAD lights” are, and it is not the same as “any bright light”. I was talking about something like this for $131: > **[Amazon.com: Verilux HappyLight Deluxe 10,000 LUX Natural Spectrum Energy Lamp :...](https://www.amazon.com/Verilux-HappyLight-Deluxe-Sunshine-Simulator/dp/B0001ATEJ2)** > > Beat the Winter Blues with the HappyLight Deluxe Energy Lamp. As many as one in seven Americans suffer from Winter Blues, believed to be caused by a lack of exposure to natural sunlight. Winter Blues can affect mood, energy, sleep, appetite and more.... It costs a lot more than a couple of light bulbs and desk lamps. And yeah, he actually said they don’t have to be full spectrum but they cost about the same and a lot of people say they like them better so I mentioned that kind. Other bright bulbs would also work, according to him. They don’t have to be compact fluorescent bulbs but you can usually get more wattage per lamp out of them, that’s why I suggested them. ---
**Author:** ![BigT](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bigt/32/12044_2.png) [@BigT](https://boards.straightdope.com/u/BigT)\ **Post date:** [December 31, 2010, 4:45am UTC](https://boards.straightdope.com/t/sad-full-spectrum-lighting/565665/10 "2010-12-31T04:45:16Z")
I’m glad people have covered what I was going to say last night, but didn’t because I couldn’t find my sources. The only thing left out is a link to a [page](http://www.psycheducation.org/depression/LightTherapy.htm) that explains it (written by a psychologist), a [page](http://www.cet-surveys.org/Dialogix/servlet/Dialogix?schedule=3&DIRECTIVE=START) that will use your sleep cycle to recommend your optimal usage time, and a recommendation. Unfortunatly, that last one is a doozy. Previously, I would always recommend this really cheap light, but it’s gotten more expensive. I got it for less than $25, but it’s apparently now going for [$40](http://www.amazon.com/Zadro-Sunlight-Artificial-Days-Year/dp/B0011UYM0C). That still makes it the cheapest device by far, though. Normal lights, BTW, can’t get to the recommended 10,000 lux. Still, not everyone needs that level. Some even people do well with a just a dawn simulator, which are mentioned in the first link above. Some people prefer a visor that uses green light, although that hasn’t been tested as thoroughly. ---
**Author:** ![Implicit](https://avatars.discourse-cdn.com/v4/letter/i/6a8cbe/32.png) [@Implicit](https://boards.straightdope.com/u/Implicit)\ **Post date:** [December 31, 2010, 5:00am UTC](https://boards.straightdope.com/t/sad-full-spectrum-lighting/565665/11 "2010-12-31T05:00:32Z")
> [@DSeid](#): > > Most protocols advise 30 minutes of exposure at 10,000 lux and longer with a less intense light source but I can find no data to support one period of time over another. > > [Early morning](http://archpsyc.ama-assn.org/cgi/content/abstract/58/1/69) seems to be most effective. 15-30 minutes in the morning works for me, if I use the light late in the day I have trouble falling asleep. When I use the light box I feel energized, almost hyper, which is a nice change from lethargic. Getting outside for a walk during the day and taking Vitamin D also helps.