Low Ferritin- What It Means and How to Fix It

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Transcript

Transcript: 

Leah: Hello everyone; welcome to “Ask a Nutritionist”, our weekly mini episode of Dishing Up Nutrition. I'm Leah Kleinschrodt, Registered and Licensed Dietitian with Nutritional Weight & Wellness. And today we're talking about low ferritin, what it means, why it matters, and most importantly, how to fix it.

Low ferritin is a topic I regularly discuss with my clients, my female clients in particular, because they will come in with symptoms of fatigue, anxiety. They're losing their hair, or they feel like their hair just isn't growing like it used to. They're experiencing shortness of breath, feeling weak or weaker than normal. Or sometimes it's just this vague feeling of feeling off, not feeling like themselves.

Many times they've gone to the doctor, maybe they've gotten some basic blood work done, and their labs, aka their hemoglobin, may technically be normal, but then we start to probe a little deeper. Something we might uncover is something called low ferritin. And this may explain all of those above symptoms.

And I really make it a point to talk to, especially my female clients, about this because I have lived this experience before. So once you live it, you don't forget it. This was eight to ten years ago now for me personally. I remember I started experiencing fatigue and I would notice it especially in my workouts. My warm-ups suddenly felt like they were the actual workout themselves.

I was getting dizzy during my workouts, and I felt like I just did not have the same output. I didn't have the same energy. I couldn't lift the same amount of weight as I was before. And it was a relatively new change. Actually, it was great that I was working at Nutritional Weight & Wellness at the time because one of my colleagues mentioned, you know, it might be a good idea for you to get your ferritin checked.

So I did, and my ferritin level was a 14 at that time. And we'll get in a little bit to what numbers we're looking for with this ferritin. But I remember the normal range for the ferritin was 12 up to something like 150 milligrams per deciliter. So my physician at that time said I was still in the normal range, which technically I was, but it was two points above that low end of the range.

And so my colleague at the time, or the dietitian I was working with, said, I think this would be a good idea if you were to supplement with a little iron and see if boosting that ferritin level up would actually help improve your symptoms. So I did. And two weeks after I started an iron supplement, I felt like I was alive again. I felt like my brain was lit up again. I felt like my workouts were so much better. It was such a profound experience. It was such a night and day difference. And again, this is why I make sure I bring this up with a lot of my female clients and I encourage them to ask their physicians to not just check hemoglobin levels, which is a different iron marker, but also test ferritin as well.

And so today I'm going to cover the ins and outs of what ferritin actually is. We'll go over those symptoms again of what low ferritin looks like. Why do we end up with low ferritin in the first place? And then again, kind of reviewing what are the best approaches to improve ferritin levels if you test and you are low.

What is ferritin?

So let's dive in. Let's answer that first question: like, what is ferritin? The simple answer is ferritin is your body's iron storage protein. So think of ferritin like your iron savings account. Your body stores iron inside of ferritin so that it has reserves available when you need it. And iron itself is known for a lot of things in the body.

I think the number one thing we think about it for is carrying and moving oxygen around in your bloodstream and bringing it to the various tissues in your body. That's an important job. But iron is also essential for making energy, supporting optimal brain function, building healthy hair, skin, and nails, supporting thyroid function, and helping your immune system work properly.

So ferritin tells us how much stored iron you have in reserve. And this is the key thing, which is again, this is what happened to me is someone can have a “normal” iron, a normal hemoglobin level. So saying that, okay, at first glance it says that your iron levels are fine. But you can still have depleted iron stores if ferritin is low.

So this is why it is important to kind of get that extra layer of testing if you can to see what that ferritin is doing. Iron on a blood test; so if you've ever had a blood test on and you just see that term iron, it usually refers to serum iron, which is the amount of iron circulating in your blood at that exact moment. And the problem is that iron fluctuates throughout the day, just depending on the time of day, what you ate, supplements you took, your level of inflammation or illness in the body.

Ferritin is much more stable because it reflects stored iron over time. So it isn't going to change an awful lot day to day. So it can be that better marker of what's going on over the longer term. So if we’re trying to understand whether someone truly has enough iron reserves, ferritin is generally more helpful than just getting that serum iron alone.

Ideal levels to shoot for + get a full iron panel

So ideally, what we want to see that ferritin level at is at least 50 nanograms per milliliter, upwards of maybe 120 nanograms per milliliter. Again, like if you look at your lab markers, if you look at a panel, if you ever have that done, you'll actually see probably a larger range for ferritin. Again, mine was down to 10 or 12 for that low end of ferritin. And the top end might be 150, 200, 250. It just depends on the lab. What we're saying is more optimal ferritin levels would probably be in that 50 to 100 or 50 to 120 nanograms per milliliter mark.

Even more ideally, we would look at a full iron panel. So this would include ferritin. It would include that serum iron. But there's some other iron markers that you can also look at. One is called transferrin saturation. One is called TIBC or total iron binding capacity. One is called CBC or complete blood count. So this is typically where you'll find that hemoglobin number. They're also looking at white blood cell count, red blood cell count, and a couple other things on that panel. And also we would love to look at a C reactive protein, which can be a marker of inflammation.

This gives us more of a comprehensive picture of iron status in general. And this matters because many people develop those symptoms of iron deficiency long before they officially become anemic. And because iron is critical for oxygen delivery and energy production and thyroid production, symptoms can affect almost every symptom in the body. I felt it when I had that low ferritin mostly around my workouts, where I was really trying to have a high energy output.

Common symptoms of low ferritin

But other common symptoms that people will feel are fatigue. So again, it might affect your workouts, even going up and down the stairs in your house. Brain fog is another symptom, dizziness, I mentioned that before, headaches, cold hands and feet, shortness of breath. So again, thinking about going up and down the stairs even at your own house or walking the block. Normally did that feel uneventful, did it feel easy and now it's a challenge? Anxiety and panic symptoms.

Poor exercise tolerance, restless legs, hair loss and hair shedding, brittle nails, rapid heartbeat, just overall weakness in general. Some people may also notice that their sleep quality really goes down. They may crave ice, and in more extreme situations, you may crave other non-food items. You may see more pale skin. This one was me, more like that feeling of being utterly exhausted and depleted after your workouts.

And again, this can happen even if someone hasn't officially developed anemia yet. Ferritin can be low even if other iron markers and hemoglobin levels are fine. So this is why I really think ferritin deserves attention before things get severe, or it's at least worth checking into for most people.

What causes low ferritin?

So now we have to ask that question: what causes low ferritin in the first place? There's several things to think about. This isn't an exhaustive list, but these are some of the ones that come to my brain initially. The first is blood loss. So again, like this makes a lot of sense with our female clients because most of us have a menstrual cycle or a cycle that hits about every four weeks. And some people have heavier bleeding than others, but that menstrual bleeding every month can significantly deplete our iron stores over time.

Other sources of blood loss might include bleeding somewhere in the digestive tract, frequent blood donation, ulcers, hemorrhoids. Female clients may have endometriosis. We may see diagnoses like IBD, so that would include ulcerative colitis and Crohn's disease, surgery, where you may lose a significant amount of blood, and childbirth is another example where women might experience a significant blood loss.

So we think about blood loss first, then we think about low iron intake in general. Many people simply aren't consuming enough absorbable iron. The most absorbable form of iron is called heme iron, and it comes from animal foods. So think red meat, beef, lamb, everyone's favorite, liver, dark meat poultry, so thighs and drumsticks, sardines, shellfish like clams and oysters.

These are going to be some of our biggest iron sources in the diet. And you may have heard that you can get iron from plants like spinach and beans and some fortified grains. But the catch there is that the plant sources of iron contain something called non-heme iron, which is not as well absorbed. So the best way to get that ferritin level up in our diet is to eat a variety of iron-rich animal-based proteins every day.

We do also have to talk about poor iron absorption, which I mentioned a moment ago, because even if you're eating some of those iron rich foods, you may not be absorbing it well. This is probably what I run into most commonly. I'd say the women that I've worked with who have had low ferritin levels, again, including myself in this, it wasn't because they were not eating meat or were not eating some beef and eating some of those seafood options and eating some high iron foods.

I tend to then question, okay, how well are we absorbing that iron? Then we start to think, okay, what gets in the way of absorbing that iron well? And one of those things can be low stomach acid and kind of hand in hand that goes with that is chronic antacid use. So antacids typically neutralize the stomach acid or reduce the production of stomach acid.

So when we don't have enough of that stomach acid, we don't have enough of that acid, that acidic environment to leach that iron out of the food. And then we absorb it further down in the digestive tract.

I also think about who else doesn't absorb iron well, someone who has celiac disease or some of those other conditions like Crohn's and ulcerative colitis, like I mentioned before. For some clients who have had gastric bypass surgery, this means that there's food that is surpassing potentially the area of the small intestine where iron gets absorbed.

So that's going to impair absorption, and just overall gut inflammation leads to lower nutrient absorption. So again, if I have a client who has chronic diarrhea, chronic constipation, a lot of bloating, gas, reflux, anything where we can tell that the gut is really bothered, we start to suspect that maybe we're not absorbing some of these great nutrients the way that we should be.

And there's certain cases also where iron requirements may be higher than baseline. These include pregnancy and postpartum, adolescence, or any period where you're in like a period of rapid growth. And also if I have somebody in front of me who they're doing a lot of intense athletic and endurance training. So maybe we're training for a marathon or we're trying to squeeze in six to seven days of training, we might be just rolling through those iron stores faster than what we can replete them with.

How can you improve low ferritin?

So all that being said, how can you improve low ferritin? I think to help people feel their best quicker, it usually requires that combination approach. The first step is we have to figure out why it is low in the first place. If someone continues to lose iron faster than they replace it, we have to ask why. So we start to go down that list. Is there bleeding somewhere? Again, heavy periods, blood donation, bleeding in the GI tract somewhere. Do we have poor digestion? Do we have low stomach acid or do we have like low digestive firepower in the gut?

Do we have diagnoses like celiac disease, Crohn's, ulcerative colitis, SIBO, which is small intestinal bacterial overgrowth? Are we eating enough protein in general? Are we overtraining? Do we just have this chronic inflammation that's kind of lingering in the background? So we do have to address why it's happening first and foremost.

Then we have to focus on increasing iron-rich foods. So think red meats, dark meat poultry. sardines, shellfish. Liver is especially rich in iron and other nutrients needed for blood building, like B12 and copper. And so if you don't love the taste of liver or some of those organ meats, one hack is you can blend it up and then blend it into other ground meat, like taco beef, so you can't taste it.

And there are some brands out there that add a small percentage of organ meats to their ground meats. One brand that I know of is called Force of Nature. They have something called their ancestral blend. And locally here in Minnesota, we have a company called Thousand Hills that does regenerative beef. They have something called their renegade blend. So again it's mostly ground beef, but they do have some amount of liver and kidney and a couple other organ meats mixed in there.

But it is a low enough percentage where you're really not going to taste it, especially if you start putting say, like tomato sauces or taco spices and other things in it. So that might be a way that you can kind of sneak some of those organ meats into your diet if you're not a huge fan, if you're like me who didn't grow up with liver and onions like my husband did.

And some tips to improve absorption include pairing iron with vitamin C foods like citrus and berries and bell peppers and tomatoes. Ideally, we try to avoid coffee and black tea with those main meals just because the tannins in those things can inhibit iron absorption. I try not to mess with people's coffee if I don't have to. So I tend to save that one for last. We try to tackle some of these other things, but that would be something just to think about is where's the timing of your coffee and black tea.

And then we do think about calcium supplements. They also can reduce absorption if they're taken, say, with an iron supplement. So ideally, try to take your iron earlier in the day and your calcium supplements a little later in the day, just to separate them out by at least a few hours.

Supplementation to consider for low ferritin

So this brings me to supplements. So we talked about the nutrition side, the food side of trying to raise that ferritin level. But we do have to talk about supplements. Once you've kind of dug a hole of low ferritin, it can be hard to get that level up quickly through diet alone. So those with low ferritin usually benefit from supplementation at least for a short period of time.

So we have to ask how do we choose an iron supplement? There's a lot of choices out there. And maybe some of you, if you've taken iron before, you know that especially these higher dose iron supplements, they can have some unpleasant GI side effects. You can have some constipation, nausea, stomach pain, or just like again, feeling kind of blah in general.

It does depend on the form of iron that is used in that supplement, though. Most forms of iron or the form of iron that tends to bother people the most is a supplement or a form called ferrous sulfate. The form that we carry here at Nutritional Weight & Wellness, and the one that I recommend, is something called ferrous bis-glycinate, and dosing it somewhere around 25 to 30 milligrams per day.

It's a smaller dose compared to again that ferrous sulfate where you'll typically see maybe 325 milligrams per day. But what this ferrous bis-glycinate means is that that iron molecule has been bound to an amino acid, specifically a glycine molecule. And that amino acid helps to carry that mineral across the gut lining. So we have much higher absorption and we have less stomach aches, nausea, constipating types of effects.

If you get a prescription from your doctor, or again, like go to a big box store and grab an iron supplement, it's typically going to be that ferrous sulfate at a higher dose, which can work to correct deficiency fairly quickly. However, it is more likely to cause more of those GI side effects and just might make it harder to stay on that supplement long enough to get the benefits that you're looking for.

I also don't typically recommend getting iron from a multivitamin. Typically, they're using cheaper forms of iron like ferric iron in there, which again is also less absorbable and requires more stomach acid, more of that acidic medium. And then iron again can compete with calcium. It might compete with other minerals. So in an ideal world, we want to separate that iron out the best we can so that we get more absorption and we kind of get the best of both worlds.

If ferritin is extremely low or someone can't tolerate oral iron at all for any reason, iron infusions are another option. And sometimes they're necessary again to just replete those iron stores as quickly as possible.

How quickly can you raise ferritin levels?

How quickly can you raise your ferritin level? It's going to depend on a couple of factors. How low was your iron to start with? How low was your ferritin to start with? What's the underlying cause of that low ferritin? And can that cause be corrected or remedied in a timely fashion?

Does your body absorb that iron well? What supplement are you taking? Are you able to do it consistently? And have we addressed any ongoing blood loss issues? So, in my experience, most people start to feel better increasing their iron intake through foods, but also getting on a supplement. They start to feel better within a few weeks. And that was my experience as well. Again, I remember two weeks in, I felt like kind of that veil had been lifted.

But rebuilding iron stores and getting them to a stable place can take up to several months. A common mistake is to stop iron supplements too early once you start to feel better. True ferritin recovery can lag behind symptom improvement. So, in other words, you might start to feel better, and yet you still might be kind of running on the low end of ferritin. So I would encourage people who have had that low ferritin and they're trying to get it back up, you probably are going to need truly somewhere between two to six months to improve it significantly.

It may even be longer, just again, depending on how severely depleted you were. And this is also why I recommend that people retest every probably six to eight weeks, especially if they're on an iron supplement. We want to make sure that it's working and that we're making headway with this lab marker.

Can GLP-1 meds cause low iron?

Now we did get a question that I want to address quickly, and it's about GLP1 medications causing low iron. So the GLP-1 medications, those injections, we're talking about things like Ozempic and Wegovy and Mounjaro and Terzepatite and things like that. So yes, potentially these GLP-1 medications can indirectly lead to low iron. And this is why: usually when people are on these GLP-1 medications, their appetite is significantly reduced.

So they're eating less food overall, which just means less food is less nutrients coming in overall. For some people, the protein intake often drops, especially for the heavier meats like red meat. A fair number of clients that I've seen can develop nausea or they just don't feel like eating. That limits nutrient intake or it limits people actually wanting to eat.

And some people also develop digestive issues that affect absorption. So again, I've seen clients who it rears up some reflux or they get more constipated or they feel more bloated. So these GLP-1 medications don't directly cause iron deficiency in everyone, but they can create the conditions that are right for depleting those iron stores and not allowing you to be able to replete them as efficiently as you were before.

So we do have to think about this, especially again for women who go on a GLP-1 medication, and they also have very heavy menstrual periods, people who are already low in iron, or maybe they have a history of already running low in iron before starting the medication. And I think about the people who already either don't eat a lot of animal protein by choice or just by beliefs or whatever the case may be.

So, anyone who is on a GLP-1 medication or thinking about starting one, it may be a good idea to just check in with a dietitian to prioritize nutrient deficiency, troubleshoot any symptoms that come up, and just also consider monitoring ferritin periodically.

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Can ferritin be too high?

Now, you can be too high in ferritin. This is less common, but I have seen it a handful of times in my clinical experience. Being too high can be a sign of iron overload. Which a lot of times this is a genetic thing called hemochromatosis, where you just don't get rid of iron well. Inflammation, liver disease can be another cause of high ferritin, metabolic dysfunction. So some of these acute inflammation settings can cause high ferritin. It highlights that there's something that the immune system is having to fight really hard in the body. So higher with ferritin is not always better.

So this is why blindly taking iron supplements without confirmed deficiency can be risky. And we do want that optimal iron balance. We want that ferritin likely between fifty to a hundred nanograms per milliliter. So we don't want it too low, but we also don't want it running amuck and having it too high. Remember, ferritin can rise acutely during times of illness, inflammation, even if iron status is poor. So we always have to interpret what we're seeing in the labs with the full clinical picture.

Wrapping it up

So, in wrapping up for this discussion, low ferritin is incredibly common, but it's also commonly overlooked. If you're experiencing things like exhaustion, hair loss, brain fog, poor exercise recovery, restless legs, dizziness, you feel cold all the time, it may be worth asking for a full iron panel.

And especially looking at ferritin. The good news is there's some other labs that sometimes doctors will balk at ordering, but in my experience, most providers are open and willing to test ferritin just to get that little bit deeper of a dive. So don't hesitate. Ask your provider, hey, if I'm going to be checking my hemoglobin, can we also check ferritin to get a better picture of what my iron is doing?

And the good news is that once you identify that root cause and properly support iron intake as well as the absorption of that iron, you can really feel dramatically better within a few weeks. So meet with a dietitian, get an idea of what you're doing from a nutrition perspective, understand how to get your levels up in a healthy and sustainable way, and see how you feel.

So I want to thank you so much for listening to “Ask a Nutritionist”. Please share this episode with someone who could use it. And if you haven't already, join our Dishing Up Nutrition Facebook group to be a part of the discussion. We'll see you next time.

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