Sun and skin

Yeah, there is a lot that is not well understood (well, not understood). I've read that study on the Hawaiian surfers, honora - counter-intuitive, isn't it. We don't even have agreement, amongst those in the field, on what represents 'normal' blood serum levels of VitD. We are a highly evolved system with many many +ve and -ve feedback loops, checkpoints etc. - 'sounds reasonable' isn't a strong argument. Any smart young things out there looking for a challenging career? Have a look at Bio-med.

Rickets is becoming a recent reality in NZ due to excessive covering up from the sun. https://www.radionz.co.nz/news/national/277515/nz-children-found-to-have-rickets @madpom Because you cant find relevant articles you expect to find on what I’m talking about does not make me a pet or a conspiracy theorist, or science denier, It would help if you let someone reply before you pay judge and jury and publicly denounce them. in general i do follow science and believe in most of what I have read. But not always. Scientific studies don’t always agree with each other, usually mainstream science gets it right, sometimes it doesn’t. Look at the argument about food with cholesterol and saturated fat, the mainstream approach had been that it was all bad for you, but better science in recent years has shown that’s not entirely the case. some research is too narrow in its focus and just points to one cause for a health issue when often there are multiple causes that all need to be taken into consideration, and that one cause isn't necessarily the villain in the picture, in some circumstances it can be one of several factors that have to work in concert with each other before they become causative factors in a health issue.

Perhaps re-read madpom's post, wayno. He's refering to a work colleague. I didn't get the sense he was critical of you. Quite probable, I think, that rickets prevalence is increasing, with kids spending more time inside, but I don't think there are national statistics collected. And, of course, there are other causes, eg genetic, to complicate the story. A simple blood test is a good idea (so you know your baseline) then consider suplementation if necessary. Note that excess VitD could be a health issue too. re scientific studies : what's reported is often (usually) not the outcome of the report - the story is packaged, simplified, spun and sensationalised by media and promoters. eg Study shows that elite athletes have increased cardiac arrest risk. Media reports "Exercise Kills - study reveals less exercise is better". PITS (person in the street) decides to stop walking to work. Newton formulated laws of motion and associated formulae that worked very well. 150 years later, a few things don't seem to fit ... and finally Einstein formulates Relativity. It's completely different but does everything Newton's work does and fills in all the bits that didn't fit and does it vastly more accurately and a lot more as well ! Was Newton wrong? No. Does Einstien contradict Newton? No, it's just a (profoundly) different way.

... and, for anyone still reading this thread, I think this is a good paper on Vitamin D and levels. https://www.racgp.org.au/afp/2014/march/vitamin-d/

In that article that JETNZ brought to my attention it says the issue with rickets isn't just low Vit D but low dietary calcium. Oh, so complicated! A study in rural South Africa showed rickets in kids over there who had adequate exposure to the sun: Rickets is often cited as proof of the need for vitamin D supplementation. However, a review of the metabolic processes involved provides some prospective. Adequate vitamin D is essential to prevent rickets, but adequate calcium is equally important; if either calcium or vitamin D is deficient, bone health suffers. Hypophosphatemia is the common denominator of all rickets; low calcium intake leads to hyperparathyroidism, which leads to high phosphorus excretion and, thus, phosphorus deficiency [44]. Rickets is rare in the developed world; however, children in developing countries, who usually photosynthesize enough vitamin D from sunlight, develop rickets if poverty prevents them from eating enough calcium-rich food [45, 46]. Studies have found that rickets occurs in sunny countries due to poor calcium intake and is cured with increased calcium ingestion [47, Still grinding through this article and then I'll read your link, Bernieq. A big interest of mine with my low Vit D, good bones (I hope) and autoimmune disease.

the issue around calcium is even more complicated , and its not actually low dietary calcium often its low absorption beause of the western diet and often low vitamin D because you need adequate vitamin D to absorb it a diet high in animal products and or refined foods is a diet high in phosphorous, the body needs to dump the excess phosphorous and calcum has a high afinity with phosphorous and gets dumped along with it when its pased out of the body, also western diets tend to be too acidic and calcium is used to neutralise acidic metabolisms and cant be used in the body elsewhere , the body will draw calcium out of the bones to neutralise the acidity as well.. it has been argued although not scientifically that people dont need the high levels of calcium claimed to stay healthy because the measurements are taken on westerners who's bodies cant use a lot of the calcium they eat and they are passing a lot of it out of the body which in theory a healthy person shouldnt do on a healthy diet. thers also claims that pasteurised dairy products have poorly absorbed calcium. calcium needs fat to be absorbed, if you are on a low fat diet, you won't absorb enough calcium.. and now everyone is told low fat diets are healthy, when they are not. you have companies selling "health foods" where they are low fat and they have had to add nutrients back in the food that were taken out when they made them low fat foods, you also need adequate vitamin k to absorb and use calcium, that also needs fat to be absorbed and is removed along with teh fat in processing of foods. or its in greens but cant be utilised without being eaten with fat. i was a vegan for decades and my bone density is fine, i wasnt on any high calcium foods,,, arguably my body was beter at using calcium because of my diet. according to the nutritional text books my bones should be weak, but i've never had any problems and tests show they are dense... teh RDA for calcium arguably takes into account the amount of calcium the average westerner passes out of their body unused which can be higher than people on traditional diets. I might talk about non standard approaches to living but i Practice what I preach, i'm willing to put myself on the line, I made difficult and serious decisions on what I believe is the truth and will try and live according to what I believe because i've found noticeable and often measureable differences to my health. I used to be crippled by chronic fatigue for years, I read a lot and made changes to my diet which radically improved my health even though they often go against mainstream thinking on diet and lifestyle. I found out the hard way what worked and what didnt, some changes were for the worse, so I made more changes until I got an improvement in my health. I dont advocate high fat diets either, I don't believe they are healthy in the long term. in the past our ancestors ate a fair amount of fat and didnt have the health issues and heart issues in the volumes that modern society does.

Thanks for the links @wayno. They give a good example of why I feel the need to be my sceptical with bold statements we keep hearing on topics such as this: For example, looking at sunlight & melonoma in your second link. The artical which you have summarised well, claims it is based on research publulished in the Lancet. Following up on the Lancet reference this turns out to be a 'rapid review' which is available here titled 'is there more than one route to melanoma?' http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(04)15649-3/fulltext The lancet review opens 'sunlight is the main cause of most cutaneous melanomas ...' Whilst the review then goes on to discuss other pathways to develop melanoma which you have mentioned yourself it certainly does not back up the opinion of the person writing on the site you linked that sun exposure is not the main cause of melanoma. I'm not advocating sticking blindly to what we believed in the past - we clearly have much more to understand and the causes of nearly all these diseases will turn out to be more complicated than we'd like to believe. But there seem to be a lot of fairly dodgy sites out there with a particular story to sell, a desire for simple headline-grabbing answers, willing to cherry pick results (or as in this case cherry pick single quotes) to back up their pet theory or sell their product. I'll get onto the other articals later and see what they have to say and what they are based upon (so appologies if they more strongly support your argument)