I recently had my vitamin D levels checked with a simple blood test. While my results came back within the optimal range (35 – 50 ng/ul which should be a minimum of 40 and preferably over 50 ng/ul), the test itself gave me pause for reflection. Vitamin D is critically important to overall health and, sadly, most of the population suffer from deficient or suboptimal vitamin D levels. Indeed, a recent study indicated that a whopping 70% percent of US children (no, folks, that’s not a type-o) suffer from deficient or insufficient vitamin D levels1. Similarly, adult men and women average suboptimal vitamin D levels and these average levels seem to be decreasing year by year2. Remember: the terms “average” and “normal” do not necessarily equal “optimal.”
Chalk the deficiency up to poor eating habits and lack of sunshine, yet, regardless of the reason behind this epidemic-level vitamin deficiency, the general health of the public is suffering. Vitamin D deficiency and insufficiency is associated with many and varied diseases as well as increased overall mortality3. Conversely, researchers in human aging have found an association between optimal vitamin D levels and increased longevity4.
If that’s not enough to send you to your doctor for a needle stick, consider these five diseases that are associated with inadequate vitamin D levels. It’s in your interest to have your vitamin D levels checked and to work on increasing those levels until you meet, but don’t exceed, the optimal range.
1. Lack of vitamin D increases your risk of heart disease.
Vitamin D deficiency and insufficiency is linked to the development of heart disease 5. Vitamin D helps your body to effectively control cholesterol, but with insufficient amounts of vitamin D circulating in your body that cholesterol can become damaged and oxidized. White blood cells then absorb the oxidized cholesterol and become what some researchers call “foam cells.” As these foam cells begin to grow in number and accumulate, heart disease begins6. Eating foods that increase inflammation within the body such as refined carbohydrates and super-heated fats – especially those fragile polyunsaturated fatty acids – coupled with vitamin D insufficiency sets up a feedback loop within the body that increases your risk of high cholesterol, heart disease and death from heart-related problems.
2. Low levels of vitamin D may impair cognitive function.
Low levels of vitamin D may also impair cognitive function – particularly in the elderly7. Elderly persons suffering from low levels of vitamin D exhibit greater signs of dementia, Parkinson’s disease and even Alzheimers disease than those with optimal vitamin D levels8. The elderly are at a particularly unique risk of suffering from low vitamin D levels as the body’s ability to manufacture vitamin D from exposure to sunlight declines as we age. Vitamin D plays a role in the reduction of inflammatory responses within the body, and it’s through this mechanism that it may prove protective from cognitive impairment associated with aging.
3. Low levels of vitamin D are associated with cancer.
Cancer is a complicated disease, and it seems that vitamin D also plays a role in this illness. Lack of vitamin D inhibits cells from functioning properly, thus increasing the risks of developing cancer9. Low levels of vitamin D have been implicated in breast, colon and prostate cancers10.
More Bloggers Talking About Vitamin D
4. Low levels of vitamin D impair bone health.
Vitamin D, calcium and vitamin K all work interconnectedly to grow and maintain our bones. In the media, we tend to hear a lot about calcium intake for health bones but calcium is only part of the story. Indeed, with inadequate vitamin D levels, calcium will do little on its own for your bones. Vitamin D deficiency, or rickets, is linked to poor bone health particularly in children and while rickets may not be wide-spread that doesn’t mean our children’s bone health is optimal. Incidentally, some researchers believe that widespread vitamin D deficiency may cause a global rise in rickets in the coming years11. A study conducted on adolescent African American girls, indicates that their consistently low levels of vitamin D inhibited the development of peak bone mass12. In essence, the girls – who are likely to face challenges to optimal bone health as they age – were already behind the curve ball during their teen years.
5. Lack of vitamin D decreases immunity to the flu and common cold.
Low vitamin d levels also decrease overall immunity and increase your risk for contracting common colds and the flu. In a three-year study conducted on the relationship of vitamin D and the common cold, researchers found that those taking supplementary vitamin D were three times less likley to report symptoms of colds and flus than control groups13. Suboptimal vitamin D levels is associated with an increased risk in developing respiratory tract infections – particularly for children under 514.
- Prevalence and Associations of 25-Hydroxyvitamin D Deficiency in US Children: NHANES 2001-2004. Pediatrics. 2009. August 3.Demographic differences and trends of vitamin D insufficiency in the US population, 1988-2004. Archives of Internal Medicine. 2009 Mar 23;169(6):626-32
- Vitamin D Deficiency and Mortality. Current Opinion in Clinical Nutrition and Metabolic Care. 2009. August 25.
- The Blue Zones: Lessons for Living Longer From the People Who’ve Lived the Longest. 2008. National Geographic.
- Vitamin D and the Cardiovascular System. CJASN. 2009. August 20.
- 1,25(OH)2 vitamin d inhibits foam cell formation and suppresses macrophage cholesterol uptake in patients with type 2 diabetes mellitus. Circulation. 2009. August 25.
- Serum 25-hydroxyvitamin d concentration and cognitive impairment. Journal of Geriatric Psychology and Neurology. 2008. December 10.
- Prevalence of vitamin d insufficiency in patients with Parkinson disease and Alzheimer disease. Archives of Neurology. 2008. October.
- Vitamin D and calcium insufficiency-related chronic diseases: molecular and cellular pathophysiology. European Journal of Clinical Nutrition. 2009. September 2.
- The vitamin D endocrine system as common cause for multiple malignant and other chronic diseases. Anticancer Research. 2006. July.
- Resurrection of Vitamin D Deficiency and Rickets. Journal of Clinical Investigation. 2006. August 1.
- Dysfunction of Vitamin-D nutrition and bone mass in adolescent black girls. Journal of the National Medical Association. 2007. June.
- On the epidemiology of influenza. Virology Journal. 2008. February 25.
- Association of subclinical vitamin D deficiency with severe acute lower respiratory infection in Indian children under 5. European Journal of Clinical Nutrition. 2004. April.
Since I started taking a Vitamin D supplement, I have had no outbreaks of a very persistent psoriasis – totally clear for a year – took some time to clear but seems to be holding
Thanks so much for this timely post! My hubby was just asking me about Vitamin D the other day (in light of his perplexity over “why take cod liver oil”)… I knew the basics (whole food, sunlight), but this helped a bit more!
Thanks, too, for the link to Nourishing Days. After reading your article I was wondering, almost to say, left hanging (nothing personal!) – what foods are good sources of Vit D? Aside from the staple CLO?
I’ve been reading your blog for about a month or so, and must say a big Thank You! overall – I really do enjoy it!
(and learn a lot!…)
Unbelievably timely post! I was at the dermatologist yesterday & asked him about vitamin D. Get this – he said there were no established values of vitamin D. And he basically said that there were no studies showing vitamin D link to disease – although he back pedaled on that a bit. He also said that there are studies showing that people in tropical climates where there is a lot more sun have vitamin D deficincies. (I was asking about spending time in the sun).
Thankfully my family doctor is more up on the issue & he had me tested a while ago. I was very deficient – like a 17 or 19 I think. After supplemnetation, I’m now at a much better level & I don’t wear sunscreen all the time. Though with a family history of melanoma (2 first-degree relatives) and very fair skin, I do wear sunscreen when I’m out for long periods of time.
Vitamin D is so important. When I worked for a holistic doctor he told everyone, especially women (because Vitamin D also helps us to use calcium better) we should have 800-1200 IU’s per day, well above what the old established recommendations are – at 400 IU’s. There have been a lot of studies about Vitamin D going on in the past few years in order to see if modification to that number is necessary. I believe it is! But at the same time, we don’t need to wait for the official word!
Thanks for this post Jenny!
I think everyone should have their Vitamin D levels tested. Despite being mostly NT and taking fermented CLO daily, I was severely deficient when tested back in March. I spent most of the summer without sunscreen and feel much better.
Where did you get tested? I have been wanting to get my levels tested as well.
Great article and am loving this site in general thanks!
Just wanted to add that it is my understanding that optimal levels of vitamin D are closer to 60 ng/ul. 35 is fairly low.
You know, I’m not totally convinced sunlight causes melanoma. Not when people seem to get it on parts of their bodies not habitually exposed to the sun. That makes no sense. Probably sun exposure plays a role in the less malignant skin cancers, because those do show up on exposed body parts–but something else may be going on with melanoma. Certainly the average person’s high-sugar diet and accompanying moderate to high insulin levels don’t help. Many, if not most, cancers feed directly on sugar by way of a fermentation process, and insulin encourages cell growth, even cancer growth.
I heard someplace that if you don’t wear sunglasses then your body can adjust how much melanin it produces to respond to sunlight. It would be nice if someone would research this, if it hasn’t been done already.
Dana -
I completely agree with you. It does not make sense! Moreover, if sunlight causes cancer how in the hell did we evolve in tropical climates? I think a lot of it, like most things, has to do with diet. Low intake of omega-3s has also been implicated in cancers and I think the high sugar diet, low omega-3s and lack of sunshine have a terrible effect on cancer in general. We gave up sunscreen a few years ago after discovering that sunscreen is carcinogenic when exposed to sunlight (uh … duh! why are we putting this on our skin?). Instead we ditch sunscreen to make sure we’re getting enough sunlight and cover up if we’ve been overexposed. That’s interesting about sunglasses, I hadn’t heard it before. Off to research!
- Jenny
I saw Dr. Oz the other day on some show and he mentioned that Vitamin D is the secret weapon against the flu. Of course, he didn’t say what kind of D to take or where it get it. I was very glad to hear that and gladder that I am taking a high quality cod liver oil.