Copyright © 2021 Natural Medicines (
February 2013

Folic Acid Supplementation May Not Affect Cancer Risk

Supplementation with folic acid may not affect cancer risk, reports a new study published in the journal Lancet.

Folate and folic acid are forms of the water-soluble B9 vitamin. Folic acid supplements are suggested for use in women of childbearing age in order to prevent neural tube defects. Sources of folate include cereals, baked goods, leafy vegetables, okra, asparagus, fruits, legumes, yeast, mushrooms, organ meat, orange juice and tomato juice.

It has been suggested to use folate cautiously in patients at risk of cancer due to increased cancer incidence in two studies. However, folate has also been reported to reduce the prevalence of certain cancers.

The new study used data from previous studies on folate supplementation. In order to be included, the previous studies had to compare a folate supplement with a placebo supplement, include participants taking folate for at least one year, and record any cases of cancer.

A total of fourteen studies and 49,621 participants were included for analysis. Researchers found a similar number of individuals developed cancer in the folate supplement groups and the placebo groups. Furthermore, a longer period of folate supplementation was not linked to an increased risk of cancer.

Researchers concluded that folic acid may not significantly increase or reduce cancer risk.

For more information about folate supplementation, please visit Natural Standard's Foods, Herbs & Supplements Database.


  1. Natural Standard: The Authority on Integrative Medicine. 
  2. Vollset SE, Clarke R, Lewington S et al. Effects of folic acid supplementation on overall and site-specific cancer incidence during the randomised trials: meta-analyses of data on 50?000 individuals. Lancet. 2013 Jan 24. pii: S0140-6736(12)62001-7.

The information in this brief report is intended for informational purposes only, and is meant to help users better understand health concerns. This information should not be interpreted as specific medical advice. Users should consult with a qualified healthcare provider for specific questions regarding therapies, diagnosis and/or health conditions, prior to making therapeutic decisions. Copyright © 2021 Natural Medicines Inc. Commercial distribution or reproduction prohibited. Natural Medicines is the leading provider of high-quality, evidence-based, clinically-relevant information on natural medicine, dietary supplements, herbs, vitamins, minerals, functional foods, diets, complementary practices, CAM modalities, exercises and medical conditions. Monograph sections include interactions with herbs, drugs, foods and labs, contraindications, depletions, dosing, toxicology, adverse effects, pregnancy and lactation data, synonyms, safety and effectiveness.