LET'S TALK ABOUT IRON.....

According to studies the proteins that provide your red blood cells the ability to deliver oxygen from your lungs to your cells, haemoglobin and myoglobin, require iron as a necessary component. This means that iron can affect your VO2 max, anaerobic energy, and overall daily active performance!! On a daily basis, your body needs around 10 - 20MG per day but how much does it actually absorb? ONLY 1-2MG per day!!

 

Dietary iron comes in two forms

heme iron (meat and seafood products) and NON-HEME IRON (plant and dairy products).  According to , Heme is known to make up more than 95%  of functional iron in our body which categorized heme as one of the most essential nutrient needed for our body.

Hrmm.. You might be wondering, what the heck is heme? Where does it come from?

To put it short, it is one of the vital components in our red blood cells. Ever heard of the word hemoglobin?

Look at the first few letters in that word. HEM which derives from the word heme. Tadaa!! 

The "heme iron," an iron porphyrin complex will combine with globin protein which makes the word hemoglobin.

Heme iron  is present in animal foods like meats and fish. They are also responsible for carrying oxygen throughout the body. So without hemoglobin our red blood cells would lose one of their function; too transport oxygen.

Now that you are equipped with a good amount of heme facts we are set to dive into how iron is truly absorbed, restored and secreted from our body! 

Your food as a whole and your iron sources can affect how much iron is absorbed. For instance, diets high in zinc and calcium can limit absorption, whereas vitamins A and C can improve your body's ability to absorb iron. That is why it is so important to catch up on your daily vitamin intakes. Do take note of this when you plan to eat something later. ;)

Now that you have eaten a good amount of vitamin C let me show you what its properties can do to your body’s iron absorption!

1) Firstly, there are two types of food that has iron which we discussed previously. Heme & Non - Heme. They both will come to the gate of Enterocyte travel from the gut lumen.

 

2) Heme, contains ferrous or Fe²⁺, is transported directly from their gatekeepers called Haem Carrier Protein 1 (HCP1) and released into the enterocyte WITHOUT ANY CONVERTION. Non - heme, on the other hand, is mostly in ferric form or Fe³⁺ but it needs to be converted into ferrous or Fe²⁺ form for absorption. Ferric reductase and Vitamin C will do the job!!

 

3) Once that is settled ferrous or Fe²⁺ will then be absorb via the Divalent Metal Transporter 1 (DMT1) and release into the enterocyte. Inside the enterocyte they will all go to the iron pool.

 

4) Inside the enterocyte all of the will gather around in the iron pool for two purpose, to be restored or transported outside the cell.

 

Hrmm.. Why does our body store some iron inside the cell? Well, everybody knows the popular Malay idiom we must prepare an umbrella before the rain right? THAT is why our body store some iron so if our body is lacking of iron intake then there are always some back up coming from the enterocyte!!

 

5) BUT! We MUST remember ferrous or Fe 2+ can NEVER be restored in the cell the way that they are. It will cause HARM to the cell. So, what should they do? The ferrous that decided to stay will be stored as FERRITIN!!

 

6) Now, how about the ones who decides they want to take a trip outside the cell? Well, speaking of transportation, even these cells need their own taxi  service. We human are obviously familiar with the app UBER or GRAB right? So what do they ride? TRANSFERRIN my dear friend.. TRANSFERRIN!!

 

7) Once these ferrous sees the exit door of these cell or FERROPORTIN (FPN), they will start barging out the door waiting for their Grab (TRANSFERRIN) to set sail to the circulation and find themselves a job!!

 

8)  These  FERROPORTIN (FPN) is inhibited by hepcidin.

 

 

WAIT WAIT WAIT!! HEPCIDIN?? That’s a big word (crying intensify)

 

Hepcidin is the main regulator of iron metabolism, is synthesized and released by hepatocytes in response to increased body iron concentration and inflammation.

 

 

So, how does hepcidin control the iron?

They will bind with a transmembrane protein called ferroportin which are found in the enterocyte, hepatocyte, placenta and macrophages!

 

ferroportin : A transmembrane protein that transports iron from the inside of a cell to the outside of the cell

 

 

9) Sadly, these transferrin don’t really recognized the existence of ferrous, ferrous are like those kids who looked like they couldn’t afford to even ride transferrin so ferrous decides to dress up fancy and become FERRIC (Fe³⁺).

 

Now, HOW DO THEY DO THAT??

 

Pretty easy really, they go to these gangsters called Hephaestin and Copper to help them get recognized and export these iron across the cell membrane using ferroxidase activity to oxidize them back to their ferric form so that transferrin can take them to the circulation!!

 

LASTLY…

10) These iron will have an exciting adventure and they will pitstop at three different places in our body!!

 

11) A group will stop at the muscle to help out in the process of myoglobin, another will make a stop at the liver to store as ferritin, and another group will go to the bone marrow that needs hemoglobin

 

 

THAT IS ALL!! THANK YOU FOR READING AND I HOPE YOU HAD A WONDERFUL TIME LEARNING HOW IRON WORKS IN OUR BODY!! TIL NEXT TIME!!

 

 PREPARED BY

Qsiratutorfi A'in Binti Mohd Zuki