03/03/2026
IRON Deficiency: why is it SO common and why is it SO hard to rectify?
I have gone down a big research rabbit hole today. Purely because for a simple little mineral, the complexity and nuances around rectifying deficiency are anything but simple! I get many cases of iron deficiency in clinic, children and adults alike, sometimes the approach is easy and straight forward, but lately, I am getting some really resistant cases, which has prompted me to dig deeper into the WHY..... I will save you from the myriad of complex pathways and try to simplify the implicating factors. First, some very interesting findings and facts to start us off..... iron deficiency is most common in women and children. Mainly in children due to their growth and development exceeding what they eat! And in women of menstruating stage, who are experiencing a regular (ish!) cycle, the biggest contributing factor is menstrual blood loss. Not to mention gut absorption factors, which is a whole other rabbit hole of inflammation, leaky gut, parasites and pathogens..... So much to know!!
The REGULATION of iron is largely controlled by an enzyme called hepcidin. Think about hepcidin like the boundcer at the club. Say the club only has capacity for 1000 patrons, once the club hits max capacity, those bouncers ain;t letting anyone else in! Until some leave, numbers dwindle, and we can open up the rope again. Similarly with iron, because iron is toxic in excess, we can only absorb approximately 50-60mg of iron in a 24 hour period..... BUT...... What I am learning more about the complexities of today, is that we only absorb about 10-20% of the iron that we actually ingest.... perhaps less in plant foods compared to animal foods Keeping in mind, the daily requirement for a menstruating woman (AFAB: assigned female at birth) is about 15-18mg daily, knowing that only about 1-3mg of that might be absorbed.....
A 200g beef steak might have 5mg of iron, only .5-1.5mg of that will pass through the gut into the blood stream.... In the case of a period, we lose on average 30-40ml of blood. We store approximately .5mg per 1ml of blood. So, if your period was average heaviness, and you lose 40ml of blood, you re losing 20mg of iron.....per period. With inadequate iron intake, with average menstrual blood loss, if you start the year with ferritn of 50, after 12 months, ferritin will drop to 10! The reference range for ferritin; stored iron: is 30-200, wiht optimal being over 80) However, like many many women battling low iron, they experience heavy bleeding, sometimes as much as 100-150ml per bleed, equating to 50-75mg of elemental iron, in one period!! Not to mention that low iron further weakens blood vessels walls, leading fto further blood loss. It is a classic chicken and egg situation.
In the case of a child, who needs around 8-10mg of elemental iron a day, you really need to think about that requirement being much higher when you take into account what food contains, as absorption is about 1/5 of the level is contains at best. for example, an egg may contain 1mg of iron, but you may only absorb .2mg through the gut inot the blood stream!
Then we factor in other nutrients that influence absorption such as B12, vitamin C Copper, B vitamins, magnesium and vitmain D.
Cracking the code of ongoing low iron or unresponsive to supplementation requires a holistic approach of considering diet, immune function, hormones/menstruation, gut health and stress...... Welcome to my brain!!!
