if this were true... then finding people whose diet naturally has high sources of vitamin D should show a low incidence of colon cancer
wiki link: http://en.wikipedia.org/wiki/Vitamin_D
from the wiki:
—
Natural sources of vitamin D include:[2]
* Fish liver oils, such as cod liver oil, 1 Tbs. (15 ml) provides 1,360 IU (one IU equals 25 ng)
* Fatty fish species, such as:
o Herring, 85 g (3 ounces (oz)) provides 1383 IU
o Catfish, 85 g (3 oz) provides 425 IU
o Salmon, cooked, 100 g (3.5 oz]) provides 360 IU
o Mackerel, cooked, 100 g (3.5 oz]), 345 IU
o Sardines, canned in oil, drained, 50 g (1.75 oz), 250 IU
o Tuna, canned in oil, 85 g (3 oz), 200 IU
o Eel, cooked, 100 g (3.5 oz), 200 IU
* A whole egg, provides 20 IU
* Beef liver, cooked, 100 g (3.5 oz), provides 15 IU
* UV-irradiated mushrooms (Vitamin D2)[30][31]
In the United States (U.S.), the 100% Daily Value used for product labels is 400 IU/day and typical diets provide about 100 IU/day. Although milk is usually fortified, the average daily consumption by most Americans is insufficient in obtaining levels of vitamin D recommended by various medical authorities.[32] While adequate intake has been defined as 200 IU/day for ages infant to 50, 400/day for 51-70, and 600/day over 70, the American Academy of Pediatrics argues that these recommendations are insufficient and recommends a minimum of 400 IU, even for infants.[33] The NIH has set the safe upper limit at 2000 IU, but acknowledges newer data supporting a UL as high as 10,000 IU/day.[34] The Institute Of Medicine is revisiting vitamin D and calcium recommendations with a report expected to be released in spring 2010.
—
considering the natural sources, i would look at eskimos and maybe the japanese to compare colon cancer rates
Of course, you would also have to factor in any gene they might have which might protect them from colon cancer.
* UV-irradiated mushrooms (Vitamin D2)[30][31]
These are yummy!
http://www.montereymushrooms.com/VitaD.htm