With the exception of rare cases of allergic reactions,555 folic acid is not generally associated with side effects,556 although there have been rare case reports of allergic reactions to the vitamin.557 Folic acid supplementation can interfere with the laboratory diagnosis of vitamin B12 deficiency, possibly allowing the deficiency to progress undetected to the point of irreversible nerve damage.558 Although vitamin B12 deficiency is uncommon, no one should supplement with 1,000 mcg or more of folic acid without consulting a doctor.
In a double-blind trial, people with diabetes who also had with kidney disease received a daily placebo or 2.5 mg of folic acid, 1 mg of vitamin B12, and 25 mg of vitamin B6 for three years. Compared with the placebo, vitamin supplementation accelerated the decline in kidney function and increased the incidence of cardiovascular events (such as heart attacks) and heart disease-related deaths.559 Based on this study, diabetics with kidney disease should not take these vitamins without a doctor's supervision.
Vitamin B12 deficiencies often occur without anemia (even in people who do not take folic acid supplements). Some doctors do not know that the absence of anemia does not rule out a B12 deficiency. If this confusion delays diagnosis of a vitamin B12 deficiency, the patient could be injured, sometimes permanently. This problem is rare and should not happen with doctors knowledgeable in this area using correct testing procedures.
Copyright © 2014 Aisle7. All rights reserved. Aisle7.com
The information presented in Aisle7 is for informational purposes only. It is based on scientific studies (human, animal, or in vitro), clinical experience, or traditional usage as cited in each article. The results reported may not necessarily occur in all individuals. Self-treatment is not recommended for life-threatening conditions that require medical treatment under a doctor's care. For many of the conditions discussed, treatment with prescription or over the counter medication is also available. Consult your doctor, practitioner, and/or pharmacist for any health problem and before using any supplements or before making any changes in prescribed medications. Information expires June 2015.