Lower vitamin D levels linked to higher risk of death

Here in the UK, until very recently, we’ve had something of a heat-wave. The sun has been shining brightly on most days and this is good news for me, as I’ve been able to take advantage of the opportunity to boost my vitamin D levels. Why is this important? Because higher vitamin D levels are associated with protection from a range of conditions including several forms of cancer, cardiovascular disease, multiple sclerosis, and bone disease, and also appears to have positive influence on factors such as muscle health and physical fitness.

The importance of maintaining optimal vitamin D levels was brought home to me again on the publication recently of a study of more than 3400 individuals aged 65 and over [1]. These individuals were monitored for more than 7 years, during which death from cardiovascular disease (e.g. heart attacks and stroke) and overall risk of death were recorded. Study participants their vitamin D levels measured at the beginning of the trial too. This allowed the researchers to assess the relationship between vitamin D levels and overall risk of death in the time period the study ran for.

What they discovered is that lower levels of vitamin D were associated with an increased risk of death, especially from cardiovascular disease.

Compared to individuals with a vitamin D level of 40 ng/ml (100 mmol/l) or more:

Individuals with vitamin D levels 10.0 ” 19.9 ng/ml were at a 47 per cent increased risk of death overall

Individuals with vitamin D levels less than 10.0 ng/ml were at a 83 per cent increased risk of death overall

Individuals with vitamin D levels less than 10.0 ng/ml were at a 236 per cent increased risk of death from cardiovascular disease

Studies of this nature (so-called epidemiological) studies are good for identifying associations (e.g. vitamin D levels and risk of death) but cannot be used to conclude that one factor is causing the other (i.e. low vitamin D levels cause death). However, what is clear is that there is a very consistent body of evidence now linking higher vitamin D levels and reduced risk of disease and death.

A year ago, I blogged about a study which, again, found lower vitamin D levels to be associated with a significantly increased risk of death. You can read about that study here.

The authors of the more recent study that is the focus of this blog call for randomized controlled trials of vitamin D supplementation ‘to determine whether this association is causal and reversible’. In other words, if giving individuals vitamin D, compared to placebo, reduced risk of death, then we know that low levels of vitamin D can cause death, and that this can be remedied.

I fully support the idea of such trials. However, chronic conditions such as heart disease tend to have long ‘latency’, which means the processes that cause these conditions tend to go on for a long time before the condition manifests. For this reason, the trials are generally going to need to be long for any real benefits to be detected. In the meantime, we do have at least some evidence that suggests there is merit in maintaining optimal vitamin levels. In 2007 the Archives of Internal Medicine published last year a ‘meta-analysis’ which grouped together several studies where death rate in those supplemented with vitamin D (dosages ranged from 300 ” 2000 IU per day) was compared to the death rate in individuals taking placebo [3]. The vitamin D supplemented individuals overall were found to enjoy a small (7 per cent) but statistically significant reduction in risk of death.

Regular readers of this blog may know that I recently had my vitamin D levels checked. They came in at a thoroughly deficient 15 ng/ml. This, despite the fact that I make a point of spending as much time in the sun as possible, and have not worn used sunscreen for about 20 years. As a result, I have taken to supplementing with vitamin D (3000 IU per day) and have just sent off a sample to have my levels re-checked. I await the results with bated breath.

References:

1. Ginde AA, et al. Prospective Study of Serum 25-Hydroxyvitamin D Level, Cardiovascular Disease Mortality, and All-Cause Mortality in Older U.S. Adults. Am Geriatr Soc, 2009 June 22 [Epub ahead of print]

2. Dobnig H, et al. Independent Association of Low Serum 25-Hydroxyvitamin D and 1,25-Dihydroxyvitamin D Levels With All-Cause and Cardiovascular Mortality. Arch Intern Med. 2008;168(12):1340-1349

3. Autier P, et al. Vitamin D supplementation and total mortality. Arch Int Med 2007;167:1730-1737

21 Responses to Lower vitamin D levels linked to higher risk of death

  1. Alan 8 July 2009 at 11:51 am #

    Good luck! My levels were 15 ng/ml too, in Feb. I then started 5000 IU for 3 months and they are now 51 ng/ml – which I am very pleased about :)

    When do you think GPs will start to test people for low vitamin D more often? A friend of mine recently asked for a test (she has type 2 diabetes and is only in her 20s!) and was refused. The Dr said that there is no point as vitamin D only helps you absord calcium and has nothing to do with her condition!

    If only there was a simple cheap test that could be done at home and give results instantly!

  2. Paul Anderson 8 July 2009 at 12:40 pm #

    John,

    Another interesting post. I will be very interested to see how your vitamin D levels have changed. My hunch is that you will need more than 3000 units a day to reach optimal levels, but its just that, a hunch.

    I started supplementing with vitamin D this year – about 10,000 units a day. I found buying vitamoin D in the UK expensive and eventually got some from the US. I have been supplementing on and off since January – probably for about 4 of the last 6 months, and every day for the last month.

    One thing I have noted this year is that I haven’t suffered from hey fever, apart from on eor two isolated sneezes. I can cut the grass and apparently suffer no ill effects – for the first time in 20+ years, I suppose. I don’t even think about it now – I do fell totally cured.

    I don’t know if it is vitamin D although that’s the only change I can associate with it. I also take cod liver oil, and have done for about 3 years and eat a very low carb diet. My symptoms have become progressively been less severe over the past
    few years.

    THe thought crossed my mind that in the past conditions for the production of vitamin D are probably optimal during the bey fever season. I wonder if it is possible that it is the combination of lack of skin exposure to sunlight and pollen actually inhibits the body’s ability to handle pollen. Maybe if we spent the majority of our time outdoors with good skin exposure to sunlight, hey fever would be far less prevalent than it is today.

    A quick google on vitamin D levels and its association hey fever produced a few hnints that there may be an association. Interestingly a fellow reader of your blog noted that his hey fever symptoms had vanished following vitamin D supplementation.

    Personally I would much rather take vitamin D in preference to anti histamines.

    Its never easy to separate out cause and effect. But the thought crossed my mind that testing hey fever suffers for vatamin D levels and supplementaing if necessary mind be a fruitful avenue of treatment for hey fever sufferers to follow. There is quite a lot to gain and little downside in so far as I can see.

    Paul Anderson.

  3. Lillea Woodlyns 8 July 2009 at 12:51 pm #

    Your website is fantastic. Just the kind of stuff I like to read. I’ve been researching this kind of thing for years. I used to be a WAPF chapter leader.

    It would be great if home test kits were available so we could check out D levels monthly at least – and the kits would have to be multi use not single and expensive like the current ones are. It would be a good thing to monitor myself year round ,,because I live in Canada. The southern tip of Canada on the West Coast, but it still isn’t ideal for D levels during the whole year.

    I was tested last year but the measurements weren’t given in the same way they are whenever I look this up. Odd. Do you happen to know what 180 pmol/L is in in ng/ml? I moved and never got the interpretation from the doctor.

    At the time of my test I was deliberately using a special sun lamp, eating a lot of ghee, and taking 500 mg of D3 every few days because before that my diet was very D deficient and I wasn’t getting much sun.

    I strongly suspect that gluten grains can reduce absorption of D in sensitive people. I quit eating gluten grains more than 3 years ago and rarely eat any grains at all, not even rice. But I think it’s too late to save my teeth. I’ve had problems with my enamel since I was quite young and I’ve read that this can be due to gluten issues (probably vitamin D malabsorption being one of the culprits).

  4. Debbie 8 July 2009 at 2:12 pm #

    Very interesting article on Vitamin D. I have an interesting experience with Vitamin D deficiency that goes along with the cardiovascular protection mentioned in your article.

    My blood pressure was high and despite the loss of significant weight and a very low sodium diet, it was remaining high. My doctor had tested me for Vitanin D deficiency and it was very low. After merely 4 days of taking Vitamin D, it has come down and has remained normal ever since.

    I consider Vitamin D my miracle supplement. It’s good to know that I am getting other benefits as well.

  5. merryweather 8 July 2009 at 9:04 pm #

    Dear Dr Briffa,

    Looking forward to hearing what your test results are! I have been taking Vitamin D3 since November 2008 and noticed positive results almost instantly. I had been feeling really depressed for no reason at all, almost weepy, getting upset by other people at the drop of a hat. None of these reactions or feelings are typical for me as I’m generally a happy-go-lucky sort of person. I put these symptoms down to SAD and perimenopause and wondered if I was simply going to learn to put up with it. Imagine my surprise when, just three days after taking approx. 4Ks per day, I suddenly felt happy – almost euphoric even!!!

    Even though I am not 100% convinced that these supplements might not have long-term side-effects, I am far more willing to take vitamin D3 than some dodgy HRT or anti-depressants.

    Oh, and by the way, to the other posters: If you Google “Grassroots Action”, you should find an organization which will do a vitamin D test for you for $40.

  6. Sharon Heydon 8 July 2009 at 11:19 pm #

    I have been reading a lot about Vitamin D deficiency and heart disease of late especially since my husbands Mother has been very unwell and has been told she has calcification of the heart valve amongst many other health problems and that her Vit D levels are low.Also my Mum has high blood pressure and osteoarthritis. I have since been taking a Vit D supplement 1000iu and I am now wandering if this is enough? And how do I know that its a good quality supplement? Could you pherhaps recommend a good quality one that I could get? Also a good quality Epa/Omega 3 fish oil supplement? How can I be sure that I am getting enough? Where can I go for blood tests to check my Vit D and other vitamin levels? I dont think my gp would do it?

  7. Jake 9 July 2009 at 12:53 am #

    Lillea:

    You are right. I just read a study that shows that grains leach Vitamin D and other valuable nutrients from the lower intestine.

    You can get a home test kit here:

    http://www.zrtlab.com/Page.aspx?nid=12&action=view&category=14&partner=VitaminD%20Council

    I compared this test with the one from Labcorp (considered to be the gold standard for Vitamin D testing). I got exactly the same result from both places.

  8. Glenice Szemere 10 July 2009 at 12:37 am #

    Hi Dr Briffa,

    Great Post, Alan and all in the UK, here is the Grassroots URL, http://www.grassrootshealth.net/

    Go there and register, answer a few questions, and for 40 american dollars they will send you a kit to do the test at home, you simply post it back to them and they email you to tell you when the test is ready, you log-in and access the results on their site. They are in the process of research and will test you every six months for 5 years ($40 per time) or you can sign up for just one year and two tests. Lots of information about “D” on that site.

    I had been taking 5,00 iu for several months, yet the test still came back at not optimum, i.e. 39 ng – 60 or higher is where I want it to be, so I have doubled it to 10,000 iu and will be interested to see the next test result in 5 months time. Recently had my hubbie sign up and he is very low too, his came in at just 20 ng.

    As far as supplementation is concerned, Dr Davies from Track your Plaque fame insists that he has only seen benefits from Vitamin D3 in an oil-base, and none or variable from the tablet form. I could not find an oil base in the UK which was not either soy-bean oil (no thanks) or rice bran oil, but I did find one in the USA who use olive oil and have had no problems having it sent to the UK so long as the total value is not more that £18, if it is, you get charged VAT plus a £10 handling charge. It usually takes about 5 – 7 days to arrive, so long as it is under the £18 total value.

    Here is the site where I get them, I buy quite a few supplements here (including NKO Krill Oil no comparison in price compared to the UK) I have been buying supplements from this comparny for a couple of years and they are very reliable.
    http://betterhealthinternational.com/productDetails.asp?prodID=N0372

    Sorry the post is so long, but I had a lot of info for you

    Glenice

  9. Dr John Briffa 10 July 2009 at 7:22 am #

    Thanks Glenice

    Grass roots for health is the facility I have used to check my own vit D levels (2nd results anticipated any day now…)

    Thanks for link to oil-based vit D supplier – very useful.

  10. Antje 10 July 2009 at 7:50 am #

    Lillea Woodlyns,

    maybe it is not too late te save your enamel. Look for the articles on vitamin K2/vitamin A/vitamin D on the website of the Weston Price Foundation. In other words, eat your cod liver oil, full fat dairy from grass fed animals and especially a japanese soyproduct called natto. Good luck!

  11. Bill Rowles 10 July 2009 at 8:50 am #

    John
    Any tips on getting blood analysis done?
    (at a reasonable cost)
    Thanks
    Bill

  12. Dr John Briffa 10 July 2009 at 9:05 am #

    Bill

    See comments 8 and 9.

  13. Irene 10 July 2009 at 10:59 am #

    I found your blog very interesting. Thank you. I have recently been diagnosed with low Vit D levels and am now taking suppliments. Almost a year ago, I was diagnosed with low B12 and started on montly injections. In retrospect, I realize that I had classic symptoms of B12 symptoms for several years prior to diagnosis. I also have IBS so suspect I have an absorbtion problem. I have had hypertension from a young age though I am not overweight, don’t smoke, rarely have alcohol and have a low fat diet. I have seen many articles linking low Vit D levels to hypertension but am not able to convince my GP. Dr Briffa, I am wondering if there is any particular study i could suggest he reads.

  14. Lisa 10 July 2009 at 12:15 pm #

    Thanks for another great post. Solgar do an oil based Vit D3 softgel. It uses safflower oil and the D3 is extracted from fish oil. The amount of oil you are taking in the capsule is pretty small though … Another good source of Vit D is lard. Or even pork scratchings. I have been searching for ages for an organic source of these – but for now I just have to make my own.

  15. Robin Dowswell 10 July 2009 at 12:47 pm #

    For Lillea Woodlyns – comment 3
    180pmol/L is:
    69,000ng/ml – which seems about 1000 time too large. Were all your units correct?
    ======
    To calculate 1st work out molecular mass of vitamin D3:
    - 385 g/mol from wiki
    180pmol/L is 1.8*10^ -10 mol/L
    multiply by 385 to get gms so:
    1.8*10^ -10 * 385 = 6.9 *10^ -8 g/L
    That is 6.9 * 10^ -5 g/ml
    and 69,000 ng/ml

  16. Dr John Briffa 10 July 2009 at 1:02 pm #

    Robin/Lilea

    I suspect that the correct units here are mmol/L which, if correct, would translate to a vitamin D level of about 70 ng/ml.

  17. Allison Anderson 10 July 2009 at 8:20 pm #

    Biocare do a liquid Vitamin D which is in an olive oil base.

  18. Terry 13 July 2009 at 1:26 am #

    I and my wife have taken 50,000 IU of D3 each day for the past two years on the advice of my good friend Dr Joe Prendergast (http://www.endocrinemetabolic.com). Dr Prendergast himself has been taking this amount for ten years and more – with extraordinary effects.

    I get my Vitamin D capsules from the following website in the USA: http://www.bio-tech-pharm.com. People in the UK should only order one batch at a time, otherwise you get hit with taxes and exhorbitant handling charges from the Post Office in the UK.

    Vitamin D3 does NOT increase your calcium. When your body has enough it stops absorbing any more and you return to normal healthy levels. The research on this was done at Bangor University Hospital in Wales.

  19. Lillea Woodlyns 15 July 2009 at 12:26 am #

    Thank you for your comments everyone!

    I assume that Dr. Briffa’s reading of my D level is correct. I can’t see how I would have been at a toxic level of D back then. I hope not! I have no idea what my level is now, though. Probably not bad because I’m getting summer sun.

    Jake – thanks for the links to the vitamin D tests! I had heard about one of them, not the other. I probably still will need to find a Canadian source due to costs.

    Hi Antje, I have read all of the articles and am friends with the author of some of them (Chris Masterjohn). I was a Weston A Price Foundation chapter leader for a long time and followed their recommendations and still do in most ways except that I had to drop gluten and I may be casein sensitive too so I have to watch it with dairy (even good quality raw dairy). Cod liver oil is only okay in small doses for me (and I’m talking about high quality cod liver oil, not the stuff on store shelves). I’m glad that Chris Masterjohn is on board with the WAPF because he has studied the negative effects of getting omega 3s in more than tiny doses.

    It would be great if my enamel improved but I kind of doubt it’s reversable. I’ve researched a lot and asked WAPF folks about it and some of them have miraculous stories but not me so far. :(

  20. health articles - Burnz 16 July 2009 at 12:51 pm #

    Vitamin D is important to our health. I read a lot of articles in dr mercola’s site and he has lots of article about how important vitamin d.

  21. Trinkwasser 16 July 2009 at 3:22 pm #

    UK sources for D3

    http://www.thevitaminservice.com/

    http://www.bodykind.com/default.asp

    both sell Higher Nature 500iu caps, cholecalciferol in sunflower oil, which are inexpensive and tiny so you can take several which may be cheaper than larger dose caps

  22. Rose Taylor 2 May 2010 at 3:38 am #

    2 years ago my son almost died from heat stroke in Afghanistan. He is back in the states now but has had problems with depression, no energy, and has problems staying asleep the military doctor put him on antidepressants, sleeping pill and pain pills the meds help with pain and sleep but he still has no energy. He never feels rested over the last 20 months the doctors have adjusted and readjusted his meds but still no relief they finally sent him to a civilian doctor who ordered a blood test and found his vitamin D levels were very low a 7.0 ng/ml . The doctor put him on 5000 IUs of vitamin D once a week what are the problems that can be caused by such a low reading and also can there be any kind of organ damage from this?

  23. Dr John Briffa 2 May 2010 at 10:21 am #

    Rose

    The very low vitamin D is probably relevant, but there might be other things going on as well. It might help to at least consider that he might be suffering from a degree of weakness in the adrenal glands.

    See here http://www.adrenalfatigue.org/ in the first instance.

Leave a Reply