Avoiding Cancer Where the “Sun Don’t Shine” with Vitamin D

April 03, 2007

Avoiding Cancer Where the “Sun Don’t Shine” with Vitamin D 

Competency # 2 The DASH Diet and #17 Vitamin D                  Reference: Am J Epidemiol 2007;165:784-793

 The evidence is starting to pile up.  Just this week in the American Journal of Epidemiology we have good solid proof about colon cancer and Vitamin D/calcium.  I’m beating this topic to death because this strategy is so important.  It makes a huge impact for so many of us.  I’ve had two deaths in my immediate family and several dear friends affected by colon cancer, so I have a bad attitude about it. 

 Here’s what was published.  In Hawaii, of all places (even there, not everyone gets enough sun), the Multiethnic Cohort Study followed 191,011 people for 7 years. Dr. Park used a food frequency method to measure calcium and Vitamin D intake. It was enough to show a 30 % reduction in men and 36% reduction in women from the top group to the bottom group of calcium consumption for colon cancer risk.  And the Vitamin D had about a 28% association for men.  It didn’t reach statistical significance for women. 

 Dr. Veith was just at St. Luke’s doing Grand Rounds on Vitamin D.  His suggestion, from his own yet unpublished research, was that there is no observed toxicity in Vitamin D with doses up to 32,000 IU a day.  The 400 IU in a Vitamin pill will only raise your blood level of D a few nanograms. 

 The unifying hypothesis is as follows.  Vitamin D helps your immature cells in your body turn into mature cells.  A cancer cell, in any organ, is an immature cell that multiplies wildly.  If it had the chance to mature into its final intended form, perhaps it would never have turned into cancer.  Vitamin D is that signaling function telling the cell to become a mature cell.   Now, living in Wisconsin, we don’t get any for 5 months, and then we live indoors and cover up our skin the rest of the year. Finally, our skin ages and loses its ability to make Vitamin D.  By age 70, we only make about 25% of what we did at age 20.  That means we need strategies to make sure we get sufficient D and calcium year around.  And sufficient is more than just 400 IU a day.  Dr. Veith suggested it might even be 5-10,000 IU a day.  He also showed evidence about other cancers and UV light.  Vitamin D is likely associated, inversely with breast cancer, bladder cancer, pancreas cancer...  are you getting the drift? 

WWW.  What Will Work for me?  I’m so eager to get my sunshine.  My wheelbarrow is out there in the yard, with snow on it, waiting for spring.  Ten minutes of sunshine, twice a week all summer will give you all you need, if you are under age 75.  Once you get to 65, you likely need 2000 IU a day year around.  It may be a lot more.  And, you also need 3 calcium servings every day.  I’m eating my yogurt, almost every day.  (That’s the DASH diet.)  My GI doctor sent me a note suggesting it’s time again…   It’s either the D or him.

The column is written by Dr. John E Whitcomb, MD, Brookfield Longevity, Brookfield, WI (262-784-5300)