Vitamin D, just like all other vitamins, is essential not just to our health, but to life itself. Vitamin D is actually not really a vitamin, because our bodies can synthsize it from cholesterol in our skin with the action of the ultra-violet end of the spectrum of sunlight. But as the specific wavelength - UVB - is attenuated by the atmosphere, there is no point in sunbathing when the sun is low in the sky. We have to be in the sun, with as little clothing on as possible, and no sunscreen, when the sun is so high in the sky that our shadow is no longer than we are. In other words, in the middle of the day. But that is exactly what we are told by the 'experts' not to do!
There is very little food which contains vitamin D. And vitamin D is one of the four fat-soluble vitamins (the others are A, E, and K). But fat is 'bad for us', isn't it! So the incompetent 'experts' also advise us to shun the only foods which can help.
It should come as no surprise, therefore, that severe vitamin D deficiency is a widespread health problem throughout the industrialised world.
Now a study just published in the European Journal of Heart Failure points out a growing serious health issue caused by this misguided advice. The Abstract of that study is below:
Israel Gotsman, Ayelet Shauer, Donna R. Zwas, et al. Vitamin D deficiency is a predictor of reduced survival in patients with heart failure; vitamin D supplementation improves outcome. Eur J Heart Fail (2012) 14 (4):357-366.doi: 10.1093/eurjhf/hfr175
Aims Vitamin D deficiency is a highly prevalent, global phenomenon. The prevalence in heart failure (HF) patients and its effect on outcome are less clear. We evaluated vitamin D levels and vitamin D supplementation in patients with HF and its effect on mortality.
Methods and results 25-Hydroxyvitamin D [25(OH)D] levels were evaluated in HF patients from a health maintenance organization (HMO), and compared them with those of the rest of the members of the HMO. Patients with HF (n = 3009) had a lower median 25(OH)D level compared with the control group (n = 46 825): 36.9 nmol/L (interquartile range 23.2–55.9) vs. 40.7 nmol/L (26.7–56.9), respectively, P < 0.00001. The percentage of patients with vitamin D deficiency [25(OH)D <25 nmol/L] was higher in patients with HF compared with the control group (28% vs. 22%, P < 0.00001). Only 8.8% of the HF patients had optimal 25(OH)D levels (≥75 nmol/L). Median clinical follow-up was 518 days. Cox regression analysis demonstrated that vitamin D deficiency was an independent predictor of increased mortality in patients with HF [hazard ratio (HR) 1.52, 95% confidence interval (CI) 1.21–1.92, P < 0.001] and in the control group (HR 1.91, 95% CI 1.48–2.46, P < 0.00001). Vitamin D supplementation was independently associated with reduced mortality in HF patients (HR 0.68, 95% CI 0.54–0.85, P < 0.0001). Parameters associated with vitamin D deficiency in HF patients were decreased previous solar radiation exposure, body mass index, diabetes, female gender, pulse, and decreased calcium and haemoglobin levels.
Conclusions Vitamin D deficiency is highly prevalent in HF patients and is a significant predictor of reduced survival. Vitamin D supplementation was associated with improved outcome.
Note the last sentence. "Vitamin D supplementation" improves survival. So they only consider treating the problem after it has been caused. What's wrong with advising people to get out in the sun more?
Incidentally, I do get out in the sun as much as possible. It doesn't need a lot: half an hour a day at midday is sufficient. I had my serum vitamin D checked a couple of weeks ago. It was 150.8nmol/L. And I aim to keep it that way.