Pregnant women need additional iron intake, but if the body controls absorption and uptake, then why is diet not enough? While it may be true that the diet doesn't provide enough, it may also include other factors beyond iron intake that may also affect women pre- and post-pregnancy.
There are many dietary factors that can inhibit iron absorption.(1) Among these factors are:
- polyphenols of gallic acid that are found in coffee and tea,
- oxalic acid of spinach, chard, berries, chocolate and tea,
- phytates found in legumes,
- preservatives like EDTA,
- phosvitin found in egg yolks;
- and other minerals such as calcium, calcium phosphate salts, zinc, manganese, and nickel.(1p422)
In addition, there are factors that enhance iron absorption. These include:
- acids like ascorbic, citric, lactic and tartaric acid
- sugars
- meat, poultry and fish
- and mucin.(1p422)
When iron deficiency is a problem, thus, wisdom would suggest considering what is inhibiting absorption and what could be added to the diet to enhance absorption.
Reference
1. Gropper, S.S., Smith, J.L. & Groff, J.L. Advanced Nutrition and Human Metabolism, 4th ed; 2005. Belmont, CA: Thomson Wadsworth.