Pernicious anemia and Cancer
Next in my ongoing series about why autoimmune diseases might actually serve a purpose--pernicious anemia. This is a condition most common among people of northern European descent. The body attacks the stomach cells that help us absorb Vit B 12---which is present in a variety of foods but in very small amounts. The symptoms and signs of pernicious anemia are 1) anemia that corrects with folic acid and 2) nerve damage that does not correct with folic acid. The standard treatment used to be b12 shots. Now it is mega doses of oral B12. If you take 2000 mcg a day orally (many times the MDR) you will absorb enough to be healthy.
Nature does not provide this oral replacement option. You would have to eat about 10 ounces of clams, the most Vit B 12 rich food, a day in order to get 2000 mcg. That's a lot of clams. Meaning that for primitive man, once pernicious anemia set in, there was little chance of beating it with a diet. Unless you were a Nordic fisherman.
So, why is a disease that makes us go numb and weak so common? What if there is some really bad cell that needs Vit B 12 in order to grow. Some cell that is much, much worse than our neurons are important. One that grows much faster than our neurons or even our normal blood cells?
http://www.webmd.com/cancer/news/20091117/folic-acid-b12-may-increase-cancer-risk
In a study of Scandinavian heart patients who took folic acid and Vit B 12
This finding was mainly driven by an increase in lung cancer incidence among the folic acid and B12-treated patients.
Seventy-five (32%) of the 236 cancer-related deaths among the study participants were due to lung cancer, and the cancer incidence among the study group was 25% higher than in the population of Norway as a whole.
Roughly 70% of all the patients in the study were either current or former smokers, including more than 90% of those who developed lung cancer.
Now keep in mind, association is not causality. However, cancer cells need folic acid--that's why methotrexate works. They need Vit B 12. So, if you could decrease your levels it is possible that you could decrease the growth of cancers.
Primitive northern Europeans would spend much of their lives indoors, in poorly ventilated caves and later in semi underground houses exposed to wood fires and coal fires and their smoke. Cigarette smoking is not the only smoke that causes lung cancer. Perhaps the excessive mortality from lung cancer in northern Europe was so high that long term nerve damage was an acceptable loss in order to slow cancer growth for middle aged women---the wisdom keepers of their tribes. An extra two to five years of life for your village wise woman might give a selective advantage over other tribes who lost their lore keeper earlier from cancer.
Vit B 12 def is no way to prevent lung cancer in the modern era when we can avoid smoke. But maybe, once upon a time, giving up your Vit B 12 was a way to eek out a few more years of life when you either lived with smoke--or died of hypothermia.
= new reply since forum marked as read
