Iron Deficiencies After Bariatric Weight Loss Surgery

Iron Deficiency and Weight Loss

Graphic from, a fantastic resource for iron information


Iron deficiency is the most common cause of anemia after bariatric surgery and can be found in 20-49% of patients.


The severity and type of nutritional deficiencies experienced by post-op patients varies based upon the type of procedure performed. As can be expected, malabsorptive procedures cause the most impact to vitamin and mineral absorption and result in deficiencies much faster, while restrictive procedures limit food (and therefore nutritional) intake, but do not bypass any part of the intestine.


Supplementation is recommended for all procedures at the levels and frequencies specific to each patient’s surgery type, loss rate, sex, age and medical history.  The inherent malabsorptive qualities of RYGBP, BPD and BPD/DS bring about a strong requirement for daily iron supplementation. Iron deficiency has been reported in many studies to be present in up to 50% of RYGBP patients, and most frequently in women.1


Amino Acid Chelate
The form of iron can make a huge difference in both absorbability and stomach irritation.  Iron as Amino Acid Chelate, is a water soluble, highly absorbable form of iron, equally as soluble as ferrous ascorbate and as absorbable as ferrous sulfate. This form of oral iron, by virtue of how it is absorbed, with iron dissociating from the chelate as it enters the nonheme pool in the same manner as other nonheme iron compounds, benefits patients with enhanced absorption and fewer side effects.1


Iron is an essential component of proteins involved in oxygen transport.
A deficiency of iron limits oxygen delivery to cells, resulting in fatigue, poor work performance and decreased immune system function.2,3  Bariatric patients post surgery, especially in the first few weeks as healing is still occurring, will need full immune function, and as much energy as possible to recover from surgery and successfully transition to daily home maintenance.


Gentle Supplementation – Ferrous sulfate is inexpensive, but many patients experience unpleasant side effects from its use, particularly gastrointestinal intolerance, which for a bariatric patient can be detrimental to supplement compliance. Symptoms such as constipation, nausea, vomiting and diarrhea, are all common, especially when ferrous sulfate is taken on an empty stomach. Comparatively, Iron bisglycinate chelate has a much lower incidence of gastrointestinal issues, and in a double-blind crossover study comparing side effects of ferrous sulfate with iron bisglycinate chelate, 61% of study participants preferred the use of the chelate for that reason.1


It is imperative that you have your blood levels checked at each follow-up visit after weight loss surgery to check for possible anemia.  If Iron supplementation is needed, a liquid iron from amino acid chelate is a great option due to high absorbability and ease of taking.  Dosage can be easily adjusted according to recommendation from your health professional.


1. Coplin, M.; Leichtmann, G.; Lashner, B. 1991 Clinical Therapeutics 13:5.
2. Miret S, Simpson RJ, McKie AT. Physiology and molecular biology of dietary iron absorption. Annu Rev Nutr 2003; 23:283-301.
3. Haas JD, Brownlie T 4th. Iron deficiency and reduced work capacity: a critical review of the research to determine a causal relationship.
J Nutr 2001; 131:691S-6S.