We're unable to sign you in at this time. Please try again in a few minutes.
We were able to sign you in, but your subscription(s) could not be found. Please try again in a few minutes.
There may be a problem with your account. Please contact the AMA Service Center to resolve this issue.
Contact the AMA Service Center:
Telephone: 1 (800) 262-2350 or 1 (312) 670-7827  *   Email: subscriptions@jamanetwork.com
Error Message ......
Article |

How Safe Are Folic Acid Supplements?

Norman R. C. Campbell, MD
Arch Intern Med. 1996;156(15):1638-1644. doi:10.1001/archinte.1996.00440140058005.
Text Size: A A A
Published online


Periconceptual use of folic acid supplements by women is effective in preventing neural tube defects in the fetus. Folic acid supplements also may prevent atherosclerosis and some malignant neoplasms. Nevertheless, safety concerns have delayed recommendations to increase folic acid consumption by the general population. Among the potential safety issues of folic acid supplementation are (1) difficulty identifying cobalamin deficiency, precipitation of neurologic complications of cobalamin deficiency, and lowering of cobalamin levels; (2) folate neurotoxicity; (3) antagonism of drugs that inhibit folate metabolism; (4) reduced zinc absorption; (5) association with malignant neoplasms; (6) hypersensitivity reactions; and (7) increased susceptibility to malaria. The data that suggest that folic acid supplements are unsafe are weak and consist predominantly of case series and reports. Nevertheless, greater difficulty diagnosing cobalamin deficiency due to "masking" of hematologic abnormalities by folic acid is a potential risk. Strict vegetarians need to be informed that they are at risk of cobalamin deficiency. Physicians need to be aware that routine hematologic indexes have a low sensitivity for cobalamin deficiency, especially in patients who are receiving folic acid supplements. Because no high-quality data exclude specific adverse effects, physicians should be vigilant in identifying detrimental effects when patients increase their consumption of folic acid.

Arch Intern Med. 1996;156:1638-1644


Sign in

Purchase Options

• Buy this article
• Subscribe to the journal
• Rent this article ?





Also Meets CME requirements for:
Browse CME for all U.S. States
Accreditation Information
The American Medical Association is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians. The AMA designates this journal-based CME activity for a maximum of 1 AMA PRA Category 1 CreditTM per course. Physicians should claim only the credit commensurate with the extent of their participation in the activity. Physicians who complete the CME course and score at least 80% correct on the quiz are eligible for AMA PRA Category 1 CreditTM.
Note: You must get at least of the answers correct to pass this quiz.
Please click the checkbox indicating that you have read the full article in order to submit your answers.
Your answers have been saved for later.
You have not filled in all the answers to complete this quiz
The following questions were not answered:
Sorry, you have unsuccessfully completed this CME quiz with a score of
The following questions were not answered correctly:
Commitment to Change (optional):
Indicate what change(s) you will implement in your practice, if any, based on this CME course.
Your quiz results:
The filled radio buttons indicate your responses. The preferred responses are highlighted
For CME Course: A Proposed Model for Initial Assessment and Management of Acute Heart Failure Syndromes
Indicate what changes(s) you will implement in your practice, if any, based on this CME course.


Some tools below are only available to our subscribers or users with an online account.

78 Citations

Sign in

Purchase Options

• Buy this article
• Subscribe to the journal
• Rent this article ?

Related Content

Customize your page view by dragging & repositioning the boxes below.