High-dose folic acid does not raise formaldehyde levels, Cornell study finds

A new Cornell University study found that high-dose folic acid does not elevate toxic formaldehyde in the body, providing reassurance for cancer patients and others taking the supplement. Previous lab tests showed tetrahydrofolate releases formaldehyde, a carcinogen, in test tubes and cell cultures, raising health concerns. However, the study in EMBO Molecular Medicine found no evidence of this toxin or DNA damage in mice or human cancer patients. Researchers examined blood from nine cancer patients taking high-dose folic acid versus 15 not taking it, finding increased folate but no formaldehyde-DNA adducts. The findings are especially relevant for Fanconi anemia patients and others requiring high supplementation.