I'd like to draw attention to some new research that shows how cancer incidence can be reduced by adequate Vitamin D3 intake.
There is a layman's guide to the research at this link
Vitamin D And Calcium Cuts Cancer Risk In Older Women, New Study Says
The results showed that women in the Calcium plus Vit D group had a 60 per cent drop in their cancer risk over the four years compared to the women in the placebo group.In order to eliminate the possibility that some women may have started the trial with undiagnosed cancers, the researchers re-analysed the results leaving out the first year's figures. This showed an even bigger 77 per cent reduction in cancer risk in the Calcium plus Vit D group compared with the placebo group.and you can find an abstract of the actual research paper at this linkVitamin D and calcium supplementation reduces cancer risk: results of a randomized trialBackground: Numerous observational studies have found supplemental calcium and vitamin D to be associated with reduced risk of common cancers. However, interventional studies to test this effect are lacking. Objective: The purpose of this analysis was to determine the efficacy of calcium alone and calcium plus vitamin D in reducing incident cancer risk of all types. Design: This was a 4-y, population-based, double-blind, randomized placebo-controlled trial. The primary outcome was fracture incidence, and the principal secondary outcome was cancer incidence. The subjects were 1179 community-dwelling women randomly selected from the population of healthy postmenopausal women aged >55 y in a 9-county rural area of Nebraska centered at latitude 41.4°N. Subjects were randomly assigned to receive 1400–1500 mg supplemental calcium/d alone (Ca-only), supplemental calcium plus 1100 IU vitamin D3/d (Ca + D), or placebo. Results: When analyzed by intention to treat, cancer incidence was lower in the Ca + D women than in the placebo control subjects (P < 0.03). With the use of logistic regression, the unadjusted relative risks (RR) of incident cancer in the Ca + D and Ca-only groups were 0.402 (P = 0.01) and 0.532 (P = 0.06), respectively. When analysis was confined to cancers diagnosed after the first 12 mo, RR for the Ca + D group fell to 0.232 (CI: 0.09, 0.60; P < 0.005) but did not change significantly for the Ca-only group. In multiple logistic regression models, both treatment and serum 25-hydroxyvitamin D concentrations were significant, independent predictors of cancer risk. Conclusions: Improving calcium and vitamin D nutritional status substantially reduces all-cancer risk in postmenopausal women.
Being able to reduce the incidence of all cancers, including skin cancer, by at least 60% and over time by 77%, simply by increasing calcium/vitamin D3 intake is very exciting. But there are a few points UK readers need to understand to obtain the same reduction in Cancer Incidence.
Firstly you need to know the research was done in Omaha USA. That is latitude 42 about the same as Rome, the sun is stronger and there are more days when UVB, and Vitamin D3, is available. From October to March very little if any UVB reaches UK. So a higher level of supplements would be needed particularly in the Winter.
The USA and Canada fortify milk, each glass contains 100iu. Europe and the UK do not fortify milk so our milk contains none. We have to add in this amount to match the USA research.
We should also take into account the fact that most of the UK population have insufficient vitamin d status. Hypovitaminosis D in British adults at age 45 yr shows that in Winter 90% of us have levels below 75nmol/L. The level at which there is sufficient Vit D3 to enable unrestricted access of it's metabolic product to all 51 tissues known to use it is 100nmol/L .
Bodies use between 3000-5000iu daily and this is an absolutely safe amount to take in Winter (October to March) as observable adverse events have only been recorded after more than10,000iu has been taken daily for more than a year.
From April to September sun exposure is free and the safest way to obtain Vitamin D3. Not only does your skin manufacture Vitamin D3 it also processes it to the next stage and this metabolic product activates the immune system by generating antimicrobial peptides that fight infection right where it is needed.
Around 310 UK people die each day as a result of those cancers that proliferate in vitamin D insufficient bodies. 77% of this represent about 240 people whose lives may not have ended if they had spent 15p a week on sufficient Vitamin D3 to keep their status optimum.
Of course not everyone will be helped but for the sake of a mere 15p is it worth the risk?