Carbonyl Iron vs Ferrous Sulfate

5:39 pm | | Comments 2

When you head to the store for your vitamins, You might notice “Iron” on the shelf. Such a simple word. It doesn’t seem that there would be much to it, but there is.

Would you believe that there are several types of iron that can be taken and they are prescribed (or chosen) based on the needs of the person taking the iron. Some iron supplements are absorbed fairly quickly and some are absorbed more slowly.

As you consider which iron supplement to take, also consider your environment. Are there toddlers in your home? Where can you keep this supplement out of reach? Iron supplements don’t hold up well in a warm, humid bathroom so that’s not a good place to keep it away from children. Take the packaging into account. Iron typically comes in a childproof bottle. Some brands put individual pills in blister packs (these will hold up in the bathroom). Access to your supplements is a personal choice, but these are a few things to think about.

The World Health Organization reports that iron deficiency is the most common form of malnutrition in the world. On the other hand, up until the 1990s, iron poisoning was the leading cause of medicinal overdose deaths in children under 6 years of age.

Many people, however, don’t need to take iron supplements. It is easy to get all the iron you need within your regular diet. It will be a little harder for someone who doesn’t eat meat to get all of their iron, but with delicious foods like spinach and almonds rich in non-heme iron, It should still be fairly easy. Easy as it may be, it is also very hard to have iron overload from foods alone. All of this to say that we all need to pay attention to how much iron is in our diets. Premenopausal women will have a harder time maintaining their iron levels because of iron lost during their period.

Other people will also struggle with iron deficiency.

Those of us who have had bariatric surgery have appetites that are so small, it’s possible, perhaps likely, to become malnourished on food alone. For those who have had gastric bypass, not only is the appetite suppressed, a significant portion of the part of the intestine that absorbs nutrients has been bypassed. To avoid the potential of malnutrition, bariatric patients are prescribed a very thorough list of vitamins and minerals to take for the rest of their lives.

Iron is a vital mineral. It is a part of the protein that delivers oxygen to muscles. Iron supports metabolism and is also necessary for growth, development, normal cellular functioning, and synthesis of some hormones and connective tissue.

Some of the most common forms of iron in supplements include ferrous and ferric iron salts. In this category I am going to address ferrous sulfate (ferrous gluconate and ferrous fumarate are very similar). I will briefly compare ferric iron to ferrous iron and I will also discuss a less common form of supplemental iron: carbonyl iron.

Finally, I will briefly discuss the advantages of dietary iron versus supplemental iron.

The Ferrous Wheel – The Main Attraction

Ferrous sulfate remains the standard and most common treatment (according to the World Health Organization) for low blood iron levels with an honorable mention to ferrous gluconate and ferrous fumarate. With a bio availability of 10-15%, these all work the same way. Ferric salts, on the other hand, are only about 3% bio available. Because of the higher bio availability of ferrous salts, gastrointestinal side effects are reported more often.

Side effects vary, but often include intestinal discomfort, heartburn, pain, constipation, flatulence, nausea and diarrhea.

There is a sustained-release ferrous sulfate that is shown to reduce or eliminate symptoms associated with taking iron supplements.

Ferrous fumarate is usually part of another vitamin like vitamin C or in a multivitamin. It was prescribed to both my wife and me after the surgeries, but when her iron got low, the doctor changed her to ferrous sulfate.

Carbonyl Iron – the Safest For You And Your Family

Caronyl Iron is absorbed much more slowly into your bloodstream than iron salts. This supplement depends on gastric acids to become soluble so this naturally means less of the side effects.

Because of the way carbonyl iron is broken down, it is widely thought to be safer for not only the patient, but for anyone who might accidentally ingest it, like a child for example.

This is the iron that interests me because of my bariatric surgery. There is a brand of supplements for bariatric patients which uses carbonyl iron. This was the first time I had seen that type of iron and it makes sense that it would be there, in that market, because bariatric patients typically need something that will be as mild as possible in our digestive tract.

The side effects can be the same as any other iron supplement, which include intestinal discomfort, heartburn, pain, constipation, flatulence, nausea and diarrhea., but are either less likely or are likely to be more mild.

Other Irons – Not A Scrap Bin

There are more than a handful of iron supplements this article isn’t covering because this is a very big subject and this page is dedicated to comparing Ferrous Sulfate and Carbonyl Iron.

My choice to talk about these two today hinged on a conversation that I had with my wife after her blood panel indicated that she is low on iron. We’ve both had bariatric surgery so I wanted to focus on iron supplements commonly prescribed to bariatric patients and on iron supplements commonly prescribed to correct low blood iron levels.

Iron – It’s What’s For Dinner

Many of you won’t eat red meat for one reason or another, but in a talk about blood iron levels, the topic isn’t covered well enough without saying that 35% or the iron available in the red meat of your choice will be absorbed by the human body in its natural state.

Sure, ferrous salts can provide much more iron and with an absorption rate of around 10-15%, you can easily absorb the same amount of iron as was in the beef, however, eating natural heme iron doesn’t come with the side effects that iron supplements come with.

It also bares mentioning that the little iron pill isn’t going to fill you up and those absorption rates are based on the iron being taken on an empty stomach. With food, you will absorb only 1/3 as much iron from a supplement when the beef would give you a full stomach AND plenty of iron.

And The Heavyweight Title Goes To…

With a very likely potential for less side effects and slower, more sustained absorption of iron, the clear winner is carbonyl iron. It is just a little harder to find and is a little more expensive. It’s worth it!

Even if you still don’t know which iron you will choose, here’s what you can do while you’re deciding:

Look up the iron content in the foods that you are eating.

Check any other supplements that you’re currently taking for iron.

See your doctor to determine if you need iron and ask them about the iron of your choice.

Learn how other foods (tea, cheese and alcohol, for example) affect iron absorption.

These steps MUST be taken to help ensure that you don’t consume too much iron.

If you’ve read this article, you are likely already needing an iron supplement and are looking for comparisons. That’s good news, you’ve done half the work, but not the most important part.

If your doctor told you to take an iron supplement, you NEED to do that now! Iron is very important!

Make taking care of you the very next thing you do!

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  1. Hello John, I enjoyed your study of these two types of iron supplements, Ferrous Sulfate, and Carbonyl Iron. I was interested to learn there was a time-release Ferrous Sulfate that caused fewer side-effects. You are very well informed! Thank you, Janice👏

    1. John Guiles says:

      Janice, Thank you for visiting my site. I strive to provide thorough, accurate, and healthful information to all!

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