Zonlicht - vitamine D - beschermt tegen vele soorten kanker (25% tot 40%) waaronder lymfklierkanker

15 mei 2007: Bron: 1: Eur J Cancer. 2007 May 29; e.a.

Meerdere studies bewijzen dat zonlicht beschermt tegen kanker. Zelfs non-Hodgkin en niet melanome huidkankers komen minder voor bij mensen die zich binnen een normaal patroon blootstellen aan zonlicht blootstellen. Alle onderzoekers wijzen erop dat zonlicht het lichaam stimuleert zelf vitamine D aan te maken en vitamine D beschermt tegen kanker. Zelfs inname van vitamine D in de vorm van een voedingsupplement beschermt tegen kanker. We hebben hieronder enkele recente studies gezet maar wie in Pubmed verder zoekt kan er nog veel meer vinden.

Does solar exposure, as indicated by the non-melanoma skin cancers, protect from solid cancers: Vitamin D as a possible explanation. Tuohimaa P, Pukkala E, Scélo G, Olsen JH, Brewster DH, Hemminki K, Tracey E, Weiderpass E, Kliewer EV, Pompe-Kirn V, McBride ML, Martos C, Chia KS, Tonita JM, Jonasson JG, Boffetta P, Brennan P.
Medical School, Department of Clinical Chemistry, University of Tampere, Tampere University Hospital, Tampere 33014, Finland.

BACKGROUND: Skin cancers are known to be associated with sun exposure, whereas sunlight through the production of vitamin D may protect against some cancers. The aim of this study was to assess whether patients with skin cancer have an altered risk of developing other cancers.

METHODS: The study cohort consisted of 416,134 cases of skin cancer and 3,776,501 cases of non-skin cancer as a first cancer extracted from 13 cancer registries. 10,886 melanoma and 35,620 non-melanoma skin cancer cases had second cancers. The observed numbers (O) of 46 types of second primary cancer after skin melanoma, basal cell carcinoma or non-basal cell carcinoma, and of skin cancers following non-skin cancers were compared to the expected numbers (E) derived from the age, sex and calendar period specific cancer incidence rates in each of the cancer registries (O/E=SIR, standardised incidence ratios). Rates from cancer registries classified to sunny countries (Australia, Singapore and Spain) and less sunny countries (Canada, Denmark, Finland, Iceland, Norway, Scotland, Slovenia and Sweden) were compared to each other.

RESULTS: SIR of all second solid primary cancers (except skin and lip) after skin melanoma were significantly lower for the sunny countries (SIR(S)=1.03; 95% CI 0.99-1.08) than in the less sunny countries (SIR(L)=1.14; 95%CI 1.11-1.17). The difference was more obvious after non-melanoma skin cancers: after basal cell carcinoma SIR(S)/SIR(L)=0.65 (95%CI=0.58-0.72); after non-basal cell carcinoma SIR(S)/SIR(L)=0.58 (95%CI=0.50-0.67). In sunny countries, the risk of second primary cancer after non-melanoma skin cancers was lower for most of the cancers except for lip, mouth and non-Hodgkin lymphoma.

CONCLUSIONS: Vitamin D production in the skin seems to decrease the risk of several solid cancers (especially stomach, colorectal, liver and gallbladder, pancreas, lung, female breast, prostate, bladder and kidney cancers). The apparently protective effect of sun exposure against second primary cancer is more pronounced after non-melanoma skin cancers than melanoma, which is consistent with earlier reports that non-melanoma skin cancers reflect cumulative sun exposure, whereas melanoma is more related to sunburn.
PMID: 17540555 [PubMed - as supplied by publisher]

1: Cancer Epidemiol Biomarkers Prev. 2007 Mar;16(3):396-400. Epub 2007 Mar 2.

Sun exposure and non-Hodgkin lymphoma.
Armstrong BK, Kricker A.
Sydney Cancer Centre, Royal Prince Alfred Hospital, Missenden Road, Camperdown 2050, Sydney, New South Wales, Australia. brucea@health.usyd.edu.au

It was initially hypothesized that sun exposure might cause non-Hodgkin lymphoma (NHL) on the following grounds: its incidence was increasing in parallel with that of cutaneous melanoma; its risk was increased in those with a history of melanoma or other skin cancer; sun exposure causes immune suppression; and immunosuppression for other reasons is associated with an increased risk of NHL. The association of NHL with prior skin cancer has been found consistently in subsequent studies, but results of ecological analyses have only partially supported this hypothesis. Contrary to it, three recent studies of NHL in individuals found that risk decreased, generally by 25% to 40%, across categories of increasing total or recreational, but not occupational, sun exposure. One study, thus far reported only in abstract, showed the opposite. Production of vitamin D from sun exposure offers a plausible mechanism for protection against NHL by sun exposure. A recent study has found a reduced risk of NHL in people with a high dietary intake of vitamin D. Results of additional studies in individuals and a planned original-data meta-analysis of case-control studies should help to resolve the present conflicting results on sun exposure and NHL.

PMID: 17337644 [PubMed - indexed for MEDLINE]

1: Int Arch Occup Environ Health. 2007 Aug;80(8):663-70. Epub 2007 Mar 2.

Occupational exposure to ionizing and non-ionizing radiation and risk of non-Hodgkin lymphoma. Karipidis KK, Benke G, Sim MR, Kauppinen T, Kricker A, Hughes AM, Grulich AE, Vajdic CM, Kaldor J, Armstrong B, Fritschi L. Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, VIC, Australia. OBJECTIVE: To investigate the association between occupational exposure to ionizing, ultraviolet (UV), radiofrequency (RF) and extremely low frequency (ELF) radiation and risk of developing non-Hodgkin lymphoma (NHL) in a population-based case-control study.

METHODS: The study population consisted of 694 NHL cases, first diagnosed between 1 January 2000 and 31 August 2001, and 694 controls from two regions in Australia, matched by age, sex and region of residence. A detailed occupation history was first obtained using a lifetime calendar and a telephone interview. Exposure to radiation was then assessed using a Finnish job-exposure matrix (FINJEM). Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated from logistic regression models that included the matching variables as covariates.

RESULTS: For ionizing radiation, the ORs were close to unity. For UV and ELF radiation, the highest exposed group of workers had ORs of 1.32 (95% CI = 0.96-1.81) and 1.25 (95% CI = 0.91-1.72), respectively. For UV radiation there was a positive dose-response when exposure was lagged by 5 and 10 years (P for trend 0.04 for both lag periods). Workers in the upper tertile of exposure for RF radiation had an OR of 3.15 (95% CI = 0.63-15.87), but the estimate was based on very small numbers. CONCLUSIONS: Our results do not provide support for an association between NHL and occupational exposure to ionizing or ELF radiation. For UV radiation, our findings are consistent with a weak positive association. Further investigation focusing on UV and RF radiation and NHL is required.

PMID: 17334774 [PubMed - in process]

Epidemiology Sun exposure may protect against non-Hodgkin lymphoma: A case-control study
Ann Maree Hughes 1, Bruce K. Armstrong 1, Claire M. Vajdic 2, Jennifer Turner 3, Andrew E. Grulich 2, Lin Fritschi 4, Sam Milliken 3, John Kaldor 2, Geza Benke 5, Anne Kricker 1 * 1School of Public Health, The University of Sydney, Australia 2National Centre for HIV Epidemiology and Clinical Research, University of NSW, Sydney, Australia 3St. Vincent's Hospital, Sydney, Australia 4School of Population Health, The University of Western Australia, Perth, Australia 5Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Australia

email: Anne Kricker (annek@health.usyd.edu.au)

*Correspondence to Anne Kricker, School of Public Health, Medical Foundation Building (K25), University of Sydney, NSW 2006, Australia Fax: +612-9036-3168

Funded by:

National Health and Medical Research Council, Australia; Grant Number: 990920

Keywords
non-Hodgkin lymphoma • aetiology • sun exposure • UV radiation • case-control study

Abstract
Ultraviolet radiation is a hypothesised risk factor for non-Hodgkin lymphoma (NHL) but no epidemiological study has examined this association using direct measures of sun exposure in individuals. Adults aged 20-74 years living in NSW and ACT, Australia, were the study population. Cases (704 of 829 invited to take part, 85%) were diagnosed January 2000 to August 2001. Controls (694 of 1,136 invited to take part, 61%) were randomly selected from state electoral rolls and frequency-matched to cases by age, sex and state of residence. A self-administered questionnaire and telephone interview measured outdoor hours on working and nonworking days and vacations at 10, 20, 30, 40, 50 and 60 years of age. Logistic regression models of NHL and sun exposure contained the 3 matching variables, ethnicity and sun sensitivity measures as covariates. Contrary to expectations, risk of NHL fell with increasing reported sun exposure hours. Relative to 1.0 for the lowest quarter of total sun exposure hours, the odds ratios (ORs) for successively higher quarters were 0.72 (95% CI 0.53-0.98), 0.66 (0.48-0.91) and 0.65 (0.46-0.91) (ptrend=0.01). The association of sun exposure on nonworking days with NHL was stronger; OR for highest quarter 0.47 (0.34-0.66) (ptrend=0.0001). Risk also fell with sun exposure on vacations; OR for highest quarter 0.60 (0.43-0.85) (ptrend=0.003). These associations appeared strongest in women and in childhood. There was little evident trend in risk with exposure on working day. Our results provide strong statistical evidence for an inverse association between sun exposure and NHL. Increasing evidence that vitamin D may protect against cancer makes UV-mediated synthesis of vitamin D a plausible mechanism whereby sun exposure might protect against NHL. © 2004 Wiley-Liss, Inc.

Received: 16 March 2004; Accepted: 21 May 2004

vitamine D, zonlicht, huidkanker, lymfklierkanker