People often ask me how much iron they actually absorb from the food they eat. Well, the truth is that there is no clear cut answer because every body is different. I can, however, provide some helpful information and benchmarks based on the Dietary References Intakes.
What Affects Iron Absorption?
When we eat food containing iron, the iron is absorbed in the upper part of the small intestine. This is the same for everybody so you’d think that finding out how much food the body absorbs would be simple, right? Well, there are things that alter the way iron is absorbed that make it difficult to sum it up in one simple answer. There are a few factors that can alter iron absorption:
Type of Iron Molecule
Meat, fish, and poultry provide us with high amounts of heme iron, which is slightly better absorbed by the body, while plant-based foods contain non-heme iron. A person whose diet is mostly vegetarian will absorb less iron than someone who eats a traditional mixed diet.
Other Ingested Substances
What you eat in the hours before or after consuming iron alters how much iron you absorb from iron-rich foods and oral iron supplements. Iron absorption inhibitors can include coffee, tea, cola, chocolate, bran, etc.
Certain people face a greater risk of developing iron deficiency than others, and certain diseases or disorders can alter the way iron is absorbed in the body. For example, celiac disease, Crohn’s disease, gastrointestinal disorders, Chronic Kidney Disease, etc.
So, What Does This Actually Mean?
While no one can really answer the question about how much iron you actually absorb, the conservative estimate is 25% for heme iron absorption and 16.8% for non-heme iron. This information is provided in the Dietary Reference Intakes from the National Academy of Science. It may not be an exact number, but it should give you a pretty good idea of what you’re getting or can get from the foods you eat. It is also very important to note that absorption is further increased in iron deficient states.
If you have low iron intake, fall into an at-risk group, and/or have symptoms such as chronic fatigue, irritability and inability to concentrate, then iron deficiency might be suspected. Please check your symptoms using the Symptoms Checker and discuss this with your primary healthcare provider for proper diagnosis.
Content and advice provided on The Iron Maiden is for information purposes only and should not serve as a substitute for a licensed health care provider, who is knowledgeable about an individual’s unique health care needs