An 89-year-old retired businessman died from an “overdose” of Vitamin D supplements that did not warn about the risks of excessive intake.
David Mitchener from Oxted, Surrey, reportedly had fatally high levels of Vitamin D when he was brought to the East Surrey Hospital last year in May and was suffering from hypercalcaemia – a build-up of calcium in the body associated with taking too much vitamin D.
He died ten days later.
Hmmm. I'm less convinced of this being a fact.
There have been at least a couple of studies done on surfers in Hawaii who are semi-professional or who report getting at least 15 hours of sun exposure per week (and we're talking a lot of time spent with their entire backs to the Hawaiian sun here too) and these studies have shown a surprising amount of vitamin D deficiency in the subjects.
Most people aren't getting anywhere near that amount of sun exposure and I'd hazard a guess that most people aren't consuming much liver in their diet.
Vitamin D synthesis with sun on skin doesn't just convert all sunlight into vitamin D. Your body will stop synthesizing it at a certain point. It's not possible to overdose from sunlight.
I'm not saying that it's possible to overdose on vitamin D synthesised by exposure to sunlight, I'm just saying that I'm unconvinced that exposure to sunlight is in itself sufficient to meet vitamin D needs without dietary intake (especially for people who live a modern lifestyle where they don't necessarily get a lot of sun exposure).
I was told by my doctor that Iron plays a part in Vitamin D absorption, so these surfers could've been deficient in that or something else that interfered with their ability to metabolise Vitamin D