We are learning more and more about the benefits and functions of Vitamin D each year and there have been several studies conducted that try to discover whether Vitamin D can play a role in either causing or aggravating depression.

Vitamin D tablets with depressed person on right
Vitamin D tablets with depressed person on right

I have always suffered with depression, particularly in the Winter months when I don’t get much sunlight.  Seasonal Affective Disorder (or as it’s know, SAD) is a common phenomenon that millions of people suffer from and the further away from the equator you go, the more likely you are to find cases of this disorder in the Winter months.  While it’s a relatively new diagnosis, it has always been here from the beginning – it’s just that doctors are now beginning to recognize and study it in more detail.

This article isn’t just about SAD – it’s about depression in general and whether Vitamin D can improve depressive symptoms.

This article has a focus on using vitamin D for depression – it isn’t an extensive look at vitamin D and you won’t find that here (I’ll be writing another blog post about that in detail).

What the research suggests

There have been many studies into depression related to vitamin D deficiency and what a coincidence that the colder (less sunny) countries have an higher depression rate.

Vitamin D is actually a hormone and not a vitamin at all.  The body can create it naturally from sunlight exposure and from vegetables containing vitamin D2.  However, if you don’t get enough exposure to sunlight then you are at risk of a deficiency.  Spending 20-30 mins in the sun with full body exposure during the summer months can create over 15-25,000 IU of vitamin D.

However, you need to ensure that the sun is at a certain degree in the sky so that the atmosphere doesn’t block the beneficial UVB rays – and that’s where it gets complicated.  You could spend all day naked in the winter sun and not generate a single IU of vitamin D.

And of course, in the summer months – people are so scared of sun exposure due to worries about skin cancer that they apply sun-blocking creams and lotions (these also block vitamin D creation).

There is a debate as to whether Vitamin D deficiency is caused by depression or whether depression is caused by Vitamin D deficiency – it’s hard to tell without more research, but in either case the fact is that there is a deficiency that needs to be resolved.

There have been many studies that mostly all suggest depression is improved with supplementation.  In some cases it’s subtle and others it is dramatic.  It all depends on the root cause of the depression.  If you have “real life” causes of depression due to trauma, relationship or financial worries then supplementing may only subtly improve the depression.  However, if you are unsure of the cause of your depression and are constantly feeling down but can’t pinpoint the cause (and perhaps it gets worse in Winter) – then you may notice drastic changes when supplementing.

In one study, Sonal Pathak included three woman with depression and measured their vitamin D status using a 25-hydroxy vitamin D test.  All three of the women were officially deficient with readings of 8.9 – 14.5 ng/mL.

After therapy to restore their levels over 12 weeks, all three women had improvements to their depression with one going from severe depression to mild depression and another improved so drastically that she has very minimal signs of depression.

Their blood levels were brought up to 32-38 ng/mL.  If they were brought up even further to say 60 ng/mL – could their depression be improved even more?  Read below for information on optimal levels.

It’s a interesting topic and something worth thinking about – it really could change your depressive status and it’s virtually harmless to give it a go with supplementing as long as you stick to the guidelines below.

What dosage to take

There is no recognized standard dosage to stick to at present.  All of the latest research is so new that there are different recommended daily intakes from many different organizations.

In the UK, the NHS have set the RDA (recommended daily allowance) to 400 IU.  This stupidly low dose is enough to prevent rickets – and thats it.  The NHS data is always 10 years out of date, from my experience.  There are even TV adverts for yogurts that provide 400 IU of Vitamin D – boasting that you get your “full daily allowance in one pot”.

In the USA, the food and nutrition board have set their allowance to 600 IU/day and 800 IU/day for elderly.

Both of these daily allowances above, are government recommendations based on dated research of Vitamin D.

This newer research has enabled organizations such as the Vitamin D Council and the Endocrine Society to set the following dosages as their recommended daily dose:

Vitamin D Council


  • 5000 IU/day – recommended
  • 10,000 IU/day – upper limit


  • 1000 IU/day per 25lbs of body weight – recommended
  • 2,000 IU/day per 25lbs of body weight – upper limit

Endocrine Society


  • 1500-2000 IU/day – recommended
  • 10,000 IU/day – upper limit


  • 600-1000 IU/day – recommended
  • 4000 IU/day – upper limit

The dose you should take is really dependant on your current Vitamin D status.  If you live near the equator or regularly take sunny vacations – you may already have good stores of Vitamin D and only need to top-up a little with 1000 IU/day.  However, if you are rarely in the sun and have cold Winters, then you may need to take as much as 5000-10,000 IU/day to replenish your stores.

Vitamin D is fat soluble, which means your body can store it for long periods of time and use the reserves you have stored when it’s needed.

Know for Sure with a 25-hydroxy vitamin D test

My 25 Hydroxy D test results from Biolab Medical Unit, London.
My 25 Hydroxy D test results from Biolab Medical Unit, London.

The best way to know your current Vitamin D status is to have a 25-hydroxy vitamin D test.  This is the most accurate test available and will give you information on your current levels of Vitamin D.  It’s best to have this test before you start supplementing and also have this test regularly whilst supplementing to know you’re aiming for your goal and not overdoing it.

I had this test before I began supplementing daily with Vitamin D (although I did take about 70,000 IU a week before the test).  You can see my test results on the image on the right.

My results were:

36 nmol/L – which is 14 ng/ml.  This was extremely low – even after I had a sunny vacation and 70,000 IU of vitamin D before the test.  I dread to think what my level was like before both of those.

What to aim for:

For optimal health and benefit from Vitamin D, you want to aim for around  50-70 ng/mL (or around 150 nmol/L).  While you would benefit from lower levels, these are the optimum for maximum health benefit from vitamin D.  However, recommendations for cancer treatment have these levels set even higher.

Don’t forget the cofactors

You should’t just take Vitamin D on its own – you should also take a few “cofactors” alongside.  Taking higher doses of Vitamin D without these cofactors could technically increase chances of arterial calcification (although you’d have to take 40,000 IU/day for several months to really cause this).

You should also be taking:

  • Vitamin K2 (preferably MK-7 variant) – this ensures that the activated calcium reaches its destination correctly (the bones) and doesn’t deposit in your vascular system.  Recommended daily when taking Vitamin D at 5000 IU/day is 100-200 mcg.
  • Magnesium (preferably ionic 100% absorbable magnesium) – magnesium is needed to convert vitamin D3 into its active form – and it uses a lot of it to do so, so 800mg/day is recommended while taking vitamin D.  You can read my lengthy article on magnesium here.
  • Complete Vitamin and mineral regime – If you eat a well balanced and organic diet, you may not need a multivitamin – however if you don’t, I highly recommend also taking a high quality multivitamin.

Not all Vitamin D is the same

It’s important to note quickly here that not all vitamin D is created or used by the body the same.

The type you are looking for (and the one I have been using) is D3.  D3 (or cholecalciferol) is the correct form that the body can work with (and it’s the one that is created from sunlight exposure).  You can also get D2 – which is what the NHS prescribe in the UK (…really!?) that is harder to convert and nowhere near as beneficial as D3.  D2 can be found in some vegetables and plants.

Please stick with D3 – it’s the most beneficial.

When taking it, ensure that you eat something with has a little fat content.  This increases absorption massively.  I take mine with a glass of milk in the morning – getting both the fat and calcium content.

How did I react to Vitamin D therapy?

My experimenting with Vitamin D has really improved my depression – I can say that for definite.  The first time I took a dose of 10,000 IU in the morning – within two hours I felt happier (significantly), had more energy and even found myself singing and jumping around.  I also noticed that I felt a little hyper (which I will explain a bit more about below).

This feeling wasn’t as strong the second day in – however my mood was greatly improved.

The first dose of 10,000 IU, I noticed that I felt a little hyper.  This is possibly to do with my magnesium levels being slightly low.  Apparently, it can cause this.  Once I increased my magnesium intake, this passed (even on the same day).

I have noticed that I am sleeping much easier – it doesn’t take me hours to sleep any more – I can drift into sleep much easier.  I also feel more refreshed in the morning because of it and my morning depression and grogginess is lifting slowly day by day.

I haven’t changed anything else in my life or supplement regime to cause improved depression – it has been vitamin D alone.

I’ll continue to take my vitamin D every morning until I reach my target level as described above.

I’ll post updates on here to let you know of my progress.

Let me know your results

I’d love to know your thoughts, questions, comments and experiences with vitamin D for depression in the comments below.  Please do post them – I’ll reply to each and every comment.

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  • Mike
    Posted April 28, 2014 at 4:39 pm

    Me and my wife both take vitamin D supplements. We each take 5000 IU’s a day. My wife has Multiple Sclerosis and it really helps her. I take because its an important part to anyones health.

  • merveille
    Posted November 11, 2016 at 11:00 pm

    my experience on vit d3 supplements

    i had the test out of the blue. because i was reading and being enlightened. it came out 11ng. i have read that it needs to be between 70 -120. above 150 it can be toxic but might not be as well. anyway.

    doctor precribed 300k iu × 2 dosages. took one directly that day. and the second one after 2 weeks. so i basically used 300.000 iu in one day with no side effects whatsoever.
    after using them i felt

    -happier more energetic also hyper
    -the day i took it at night made me wake up at 7 crazy energised and want able to sleep back. it is rare for me. very rare.(maybe because it contradicts melatonin as this one is sunlight hormone and other one is associated w sleep and is a nighttime hormone? just guessing.)
    -dramatically less plaque in my teeth in the following 7 days after both dosages
    -dramatically less hairloss (but now after a month the hairloss came back

    -no muscle aches
    no bone aches
    -lifted mood and more stable mood
    -first time in my 23 years of adult life i didnt have pms or cramps in my period. which is a miracle.

    -better sleep.no waking up in the middle.
    -better digestion.
    -less brainfog

    dont know what my level is now. will get tested asap. i guess its around 30..

    will update . take care

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