High Plasma Folate Levels May Increase Risk for Prostate Cancer

[Guest guest]

Guess I'd better get my B12 & Folate levels down...

NEW YORK (Reuters Health) Feb 11 - Adequate folate levels are thought to

protect against malignant tumors, but results of a prospective study suggest

that folate may actually stimulate the development of prostate cancer.

At Umea University Hospital in Sweden, Dr. Johan Hultdin and colleagues

analyzed plasma folate, vitamin B12, and homocysteine levels in 254 men with

prostate cancer and 514 matched control subjects. All of the men were

members of the Northern Sweden Health and Disease Cohort.

The researchers report in the February 20th issue of the International

Journal of Cancer that men in the highest quartiles of plasma folate and

vitamin B12 levels had odds ratios for prostate cancer risk of 1.6 and 2.63,

respectively, compared to subjects in the lowest quartiles.

Higher plasma homocysteine levels were associated with a reduced risk of

prostate cancer, but this finding was only of borderline significance.

When the investigators adjusted for body mass index and smoking, the

increase in risk was significant only for vitamin B12. In fact, the authors

add, the 3-fold increase in risk associated with vitamin B12 was independent

of age at study entry, follow-up time, and disease stage at diagnosis.

" Our results suggest that factors involved in maintaining an adequate folate

status are not protective against prostate cancer, and that high plasma

levels of folate and especially vitamin B12 may even have a detrimental

effect, " the researchers conclude.

Int J Cancer 2005;113:819-824