UV eksponering og vitamin D status Vitamine A

							          Vitamin D security in northern
          Norway in relation to traditional
          sea food and UV-B light.

 Magritt Brustad1, Torkjel Sandanger1,2, Kåre Edvardsen2, and Ola
                             Engelsen2
1Centrefor Sami Health Research, Institute of Community Medicine, University
                               of Tromsø, Norway
2 Norwegian Institute for Air Research, The Polar Environment Centre, Tromsø,
                                     Norway.
Vitamin D and health
 Vitamin D is essential for natural bone
 metabolism
 Calcium and phosphate regulation
Vitamin D and bone health




        Skallelv, Finnmark, 1930
Vitamin D and health
 Cancer protective?
 Protect against autoimmune diseases?
Sources of vitamin D
 Diet
   Fatty fish
   Cod liver oil
   Fortified butter and margarine
 The sun
   UVB-radiation
The sun as vitamin D source
 Photoconvertion of pro-
 vitamin D in skin to
 vitamin D3
 Activated in liver and
 kidneys
 Vitamin D3 from skin =
 vitamin D3 from diet
Sun induced vitamin D
 Dependent on the sun ray’s qulaitative and
 quantitative properties
   Wave length
   Clouds
   Ozone thickness
   Surface reflection
   Sun angle – geography and season
”The Vitamin D winter” - UV-hours
Sun induced vitamin D
 Individual level
   Skin type
   Sun exposure behaviour
   Clothes
   Use of sun tan cream/sunblock
   Time spent in the sun
Clouds absorb the UVB-light
    Tromsø, 28 Juli 2006




Obtain vitamin D equal to 10 μg:
- outdoor approx. 46 min with hands and face exposed (10% of the body)
- outdoor approx. 16 min with 25 % of the body exposed
   Tromsø 22. July 2006




~ 7 hours outdoor gives vitamin D equal to 10 μg
 Tromsø, 26 March 2006




Outdoor 17 min equivalent to 10 μg vitamin D
Predictors for vitamin D status in
northern Norway (n=300)
 Season
 Sun holiday and Solarium
    Mean: 25(OH)D: 66 vs. 53 nmol/l
 Vitamin D intakes (cod liver oil included)
    Subjects with 25(OH)D >37.5 nmol/l
      Mean intake = 6,8μg/d
    Subjects with 25(OH)D <37.5 nmol/l
      Mean intake = 3,2 μg/d
 Been in northern Norway the whole summer
    Mean 25(OH)D: 54 vs. 60 nmol/l


                     Brustad et al. (2004) Public Health Nutr. 7:327-336
       •Rickets prevelence =
       60-70 %
       •Related to access to
       fish liver
       •Fish liver the main
1931
       vitamin D source
Proportion that consumed fish-liver 7 times or
more/season, Troms county (Women and cancer
study, 1998)
Vitamin D and traditional sea food

                  90
                  80
                  70
      utvalgene




                  60
                  50                                             Tromsø n=33
 % av %




                  40                                             Skjervøy n=32
                  30
                  20
                  10
                   0
                       <37,5 nmol/l   37,5-50,0     >50 nmol/l
                                       nmol/l
                          Utgangsverdier for plasma 25(OH)D
                                      25(OH)D
      Fish liver – a traditional source of
      vitamin D
                           Seasonal variation in 25(OH)D by fish liver
                                         consumption

                          60,00
                          50,00
         25(OH)D nmol/l




                          40,00
                                                                      fish liver
                          30,00
                                                                      no fish liver
                          20,00
                          10,00
                           0,00
                                  Oct   Dec   Feb   April June Sept

n=60, from a coastal community in northern Norway (Andenes)
Brustad M, et al (2007) Photochemistry & Photobiology Sciences. 6, 903-8.
One meal with ”mølje” provides
(Cod, cod-liver and hard roe) :

  12 recommended daily doses of vitamin D
  11 recommended daily doses of vitamin A
  1 recommended daily dose of vitamin E
  14 g DHA + EPA
  24 μg sum PCB
  Benefits and risks


   ÷                      +
                       High nutrient density
Contaminants
                       Health effects
                       Social and cultural values
                       Taste
                       Knowledge
                       Cost-saving
Fish liver consumption and
POPs
 POPs level in blood was not explained by fish
 liver intake in a coastal population in northern
 Norway (Skjervøy) (age and gender predicted
 POPs levels)
      Sandanger TM et al. (2006) J. Environ. Monit., 8, 552 -
      557.
 Fish liver was an important source of vitamin D
      Brustad M et al. (2004) Publ. Health Nutr. 7(6), 783-789.
Journal of Environmental Monitoring, 2007
Women and Cancer study n=(62076)
Fish liver consumption was not associated with
an increased cancer risk in breast, uterus, or
colon
  8 % decreased risk for total cancer was found.
Conclusion
 The population in northern Norway depends
 on dietary sources of vitamin D
 Consumption of traditional sea food in
 northern Norway prevents vitamin D levels to
 drop considerably during winter and
 contributes to maintain good vitamin D status
 in the population.