Knowledge Check

Iron deficiency following bariatric surgery

Lupoli et al:

Iron deficiency, expressed by low serum ferritin, occurs in more than 30% of patients after 5 years from surgery, with a similar rate after RYGB and sleeve gastrectomy… Iron-deficiency can be attributed to several causes. Reduced iron absorption due to hypocloridria and the bypassing of the duodenum and proximal jejunum (which are the main sites of iron absorption) are the primary mechanisms that lead to iron deficiency. Post-operative reduction in food intake and changes in food preferences, such as intolerance for meat and dairy products, are important contributory factors.

World J Diabetes 2017 November 15; 8(11): 464-474

Which type of iron is more efficiently absorbed?

a
Non-heme iron (e.g., plants)?
In addition to being less well absorbed compared to heme iron, non-heme iron is subject to significant modulation by dietary elements. For example, its absorption is increased by vitamin C, citric acid, and other organic acids, and inhibited by phytates, polyphenols and calcium.
b
Heme iron (e.g., meat)
Intake of iron in the heme form has higher bioavailability than in the nonheme form. Approximately 10–15% of heme iron is available in an omnivorous diet rich in meat.

True of false: vegetarians and vegans are at higher risk of developing iron deficiency.

a
True
b
False