Feeling tired all the time, short of breath, or unusually pale? If you’re going through cancer treatment or supporting someone who is, these signs might not just be side effects—they could mean low hemoglobin levels. And yes, certain types of cancer are more likely to cause that drop.
In this blog, we’ll explore how hemoglobin works, why it matters, and which types of cancer causes low hemoglobin levels. We’ll also discuss symptoms to look out for and how doctors manage it. Let’s dig in—because understanding what’s happening inside your body helps you take charge of your health.
Understanding Hemoglobin and Its Role
To begin, hemoglobin is a protein found in your red blood cells. Its job? Carry oxygen from your lungs to the rest of your body and bring carbon dioxide back to the lungs so it can be exhaled. Simple, right? But it’s crucial.
When your hemoglobin levels drop, your body struggles to get the oxygen it needs. This can lead to fatigue, dizziness, and even complications if left untreated. While low hemoglobin—often referred to as anemia—can happen for many reasons, cancer is one of the bigger culprits.
Moreover, the body relies on healthy bone marrow to produce enough red blood cells. When cancer interferes with this process, that’s when trouble starts.
So, how exactly does cancer get in the way of normal hemoglobin production? Let’s break that down next.
How Cancer Affects Hemoglobin Levels
There’s no single way cancer impacts hemoglobin—it tends to be a combination of factors. Here are the most common ways it happens:
- Bone marrow disruption: Some cancers invade the bone marrow, reducing its ability to produce red blood cells.
- Chronic blood loss: Tumors in areas like the stomach or intestines may cause slow, hidden bleeding.
- Inflammation: Cancer triggers inflammation, which can suppress red blood cell production over time.
- Nutrient deficiencies: Chemotherapy or the cancer itself can interfere with how your body absorbs iron, B12, and folate—all of which are essential for red blood cell production.
On top of that, treatments like chemo and radiation often affect healthy cells too. Your red blood cells may take a hit, leading to anemia.
That brings us to the big question: which types of cancer are most likely to cause low hemoglobin?
Which Types of Cancer Are Most Likely to Lower Hemoglobin?
Not every cancer will cause low hemoglobin, but some are known to increase the risk significantly. Here’s a closer look at the main culprits.
Blood Cancers (Leukemia, Lymphoma, Myeloma)
These cancers start in the blood-forming tissues, like the bone marrow or lymphatic system. Since hemoglobin is part of red blood cells—which are made in the bone marrow—it’s easy to see how things can go wrong.
- Leukemia crowds out healthy blood cells with immature white cells.
- Lymphoma can spread to the bone marrow, disrupting production.
- Multiple Myeloma directly affects plasma cells in the marrow, impacting red blood cell output.
Patients with these cancers often experience persistent anemia, which can be severe if left unmanaged.
Gastrointestinal Cancers
Colon, stomach, esophageal, and rectal cancers fall into this category. One of the major issues here is slow, internal bleeding.
You might not see the blood, but it’s there—usually in the stool. Over time, this hidden loss leads to iron deficiency and low hemoglobin.
Moreover, these cancers often interfere with nutrient absorption, making it harder for your body to rebuild lost red cells.
Gynecologic Cancers (Cervical, Uterine, Ovarian)
Many gynecologic cancers cause irregular or heavy bleeding, especially in the uterus or cervix.
In addition, ongoing blood loss can go unnoticed or be dismissed as a menstrual issue. But when it’s tied to cancer, the impact on hemoglobin can be significant.
This issue isn’t limited to younger women. Postmenopausal women with unexplained bleeding should get checked—it’s often one of the first warning signs.
Kidney and Bladder Cancer
Here’s something you might not know: your kidneys produce a hormone called erythropoietin (EPO). This hormone tells your bone marrow to make red blood cells.
When kidney cancer interferes with this process—or if surgery or damage affects one or both kidneys—EPO production drops. That means fewer red cells and, you guessed it, lower hemoglobin.
Bladder cancer can also cause blood in the urine (hematuria), which can become a chronic loss over time.
Lung Cancer
Lung cancer might not be the first thing you think of when it comes to anemia, but it’s actually quite common in these patients.
Why? Because lung tumors can bleed, cause inflammation, or make it harder to absorb nutrients due to appetite loss and treatment side effects. Add in decreased oxygen-carrying capacity, and fatigue becomes even worse.
All in all, these five types of cancer are the most common contributors to low hemoglobin levels. But how can you tell if you’re affected?
Signs You Might Have Low Hemoglobin During Cancer
It’s easy to write off certain symptoms as “just part of cancer,” but low hemoglobin has its own set of clues. Here are some to watch for:
- Constant fatigue or weakness
- Shortness of breath—even during light activity
- Pale or yellowish skin
- Dizziness or lightheadedness
- Rapid or irregular heartbeat
- Cold hands and feet
These symptoms may appear gradually or worsen over time. Either way, they’re worth mentioning to your doctor.
Next, let’s look at how healthcare providers typically treat low hemoglobin in cancer patients.
Managing Low Hemoglobin Levels in Cancer Patients
The good news? There are several ways to manage low hemoglobin and help you feel better.
Common Treatment Options:
- Iron supplements: Especially if iron deficiency is part of the issue
- Blood transfusions: Used when hemoglobin drops quickly or severely
- Erythropoiesis-stimulating agents (ESAs): These medications encourage red blood cell production
- Treating the root cause: Like stopping internal bleeding or adjusting chemo
In addition, a balanced diet with iron-rich foods (leafy greens, red meat, fortified cereals) can support recovery. That said, nutrition alone isn’t always enough during active cancer treatment.
Working closely with your doctor or oncology team ensures you’re getting the right support, especially since each case can be different.
Conclusion
Low hemoglobin levels are more common in cancer patients than many people realize. Knowing which types of cancer cause it and what symptoms to look out for can make a huge difference.
Here’s a quick recap:
- Blood, GI, kidney, lung, and gynecologic cancers are the top culprits.
- Symptoms include fatigue, shortness of breath, and dizziness.
- Treatments are available and can improve your energy and quality of life.
If you or a loved one is going through cancer and noticing these signs, don’t brush them off. Speak to your healthcare provider and ask whether additional support or treatment might help.
Ready to take the next step? Consider asking your doctor about current options and even exploring clinical trials for cancer that could open doors to new therapies.
