Low Hemoglobin Levels: Causes, Symptoms, and Treatment (2024)

Low hemoglobin means you don't have enough of the red blood cells that carry oxygen throughout your body. When you have low hemoglobin, your cells and tissues don't receive as much oxygen as they need, which can make you feel weak and tired.

Low hemoglobin levels can be caused by a diet low in iron, gastrointestinal (GI) bleeding, GI surgery, and heavy menstrual bleeding, among other things. Some of the symptoms related to low hemoglobin include body aches, chest pain, weakness, fast heartbeat, and shortness of breath.

What Low Hemoglobin Means

Hemoglobin is a protein in your red blood cells. It transports oxygen from your lungs to the rest of your body and removes carbon dioxide from your lungs. When your hemoglobin levels are too low, it means your blood can't complete these tasks as efficiently.

What Happens When Hemoglobin Is Too Low?

When your hemoglobin is too low, you may experience a range of symptoms related to the lower levels of oxygen in your body. Low hemoglobin symptoms may include:

• Body aches
• Brittle nails
• Chest pain
• Feeling dizzy or fainting
• Feeling weak
• Having cold hands and feet
• Having a fast heartbeat
• Having a sore or swollen tongue
• Headache
• Irritability
• Pale skin
• Shortness of breath
• Trouble concentrating
• Trouble sleeping
• Wanting to eat unusual things like dirt or ice
  

What Causes Low Hemoglobin?

There are a few possible causes of low hemoglobin.

Bleeding Problems

Some examples of bleeding problems that can lead to low hemoglobin include:

• Heavy menstrual bleeding
• Ongoing bleeding in your (GI) tract from colon cancer or an ulcer
• Bleeding in your gastrointestinal tract caused by the overuse of aspirin or nonsteroidal anti-inflammatory drugs (NSAIDs) like Aleve (ibuprofen).

Problems with Red Blood Cell Production

Your body produces red and white blood cells in your bone marrow. But your body may not make enough red blood cells if you have conditions that affect your bone marrow’s ability to produce or support enough red blood cells. Examples include:

• Aplastic anemia and pernicious anemia
  
• Chronic kidney disease
• Chemotherapy

Cancers that can cause low hemoglobin production include:

• Leukemia
• Lymphoma
• Multiple myeloma
  
• Myelodysplastic syndromes

Problems with Red Blood Cell Lifespan

Sometimes your body produces enough red blood cells, but the cells are dying faster than your body can replace them. Conditions where this happens include:

• Enlarged spleen (splenomegaly)
• Sickle cell anemia
• Thalassemia

Low Nutrient Intake

You may have low hemoglobin if:

• Your body can’t absorb iron, which affects your body’s ability to make red blood cells.
• Your diet is low in iron. You get iron from the foods you eat. Even though not all of the iron is absorbed by your body, a diet low in iron can lead to iron deficiency anemia.
• You’re not getting enough essential nutrients like vitamins B12 and B9, which can lead to pernicious anemia and megaloblastic anemia.

Other Causes

Other reasons you might have low hemoglobin levels include:

• Recent gastrointestinal (GI) surgery that caused your body to poorly absorb iron
  
• Donating a lot of blood
• Major changes to your body, such as a pregnancy or, in children, a growth spurt

Low Hemoglobin Levels in Infants

Newborns can have temporary anemia at six to nine weeks if they haven't made enough new red blood cells and have used up the ones they were born with. This anemia usually resolves on its own.

Babies can also have anemia from breaking down red blood cells too quickly if the mother and baby have different blood types.

However, most newborns have sufficient iron stored in their bodies for about the first six months of life. After six months they need an additional source because breast milk doesn't contain enough iron. Iron-rich foods, iron-fortified cereals, iron-fortified formula, or iron supplement drops can be added to the baby's diet to help prevent low hemoglobin levels in infants.

How Are Hemoglobin Levels Tested?

The symptoms of low hemoglobin are similar to the symptoms caused by many other medical problems. That's why it is important to see your healthcare provider if you have these symptoms so they can determine the true cause.

To help diagnose and then treat low hemoglobin, your healthcare provider will order a blood test called a complete blood count (CBC). This test will measure your hemoglobin level and red blood cells. Your provider will likely also perform a physical exam and other diagnostic tests.

Low Hemoglobin Treatment

Treatment of low hemoglobin will depend on your age, the severity of your low hemoglobin, and the cause. In particular, treatment for iron deficiency anemia may include:

• Iron supplements taken orally a couple of times a day: This is the most common treatment for iron deficiency. Always check with your healthcare provider before using iron supplements. Let them know if you experience side effects, such as vomiting or diarrhea.
• Iron therapy that delivers iron through a blood vessel: This is more common for severe iron deficiency anemia. It also is more commonly used in those with iron deficiency anemia who also have chronic conditions such as celiac disease or kidney disease.
• Red blood cell transfusions: These can raise the number of red blood cells and iron in your blood.
• Surgery that stops the bleeding that is leading to iron deficiency anemia: Your healthcare provider also may perform procedures like an upper endoscopy (EGD) or colonoscopy to find the cause of bleeding.

You may be able to help fix low hemoglobin levels by adding more iron-rich foods to your diet. These include:

• Beans and legumes
• Fish
• Leafy greens like collards and kale
• Meat
• Poultry like chicken and turkey
• Tofu

Consuming more foods that are rich in vitamin C, such as citrus fruits, can improve your iron absorption.

When to See a Healthcare Provider

Slightly low hemoglobin levels aren't necessarily a cause for concern. Some people have naturally lower hemoglobin than others.

If your hemoglobin levels are very low or you have symptoms such as fatigue, shortness of breath, unusually pale skin, or dizziness and lightheadedness, talk to your healthcare provider.

Preventing Low Hemoglobin Levels

It isn't always possible to prevent low hemoglobin. When you have preventable iron deficiency anemia, the most effective strategies include:

• Consuming more foods with iron: Most people with iron deficiency need 150–200 milligrams (mg) per day of iron.
• Making healthy food choices in general: Eating foods like leafy green vegetables (such as kale, spinach, and romaine lettuce), beans, and lean proteins helps your body to get iron and other vitamins that it needs.
• Talking to your healthcare provider if you experience unusual blood loss: This can include heavy periods or blood in your stool.
• Talking to your healthcare provider if you use calcium supplements: This is because the body has a harder time absorbing iron with calcium. Your healthcare provider may suggest another way to get calcium.

Summary

There are several causes of low hemoglobin related to problems with bleeding, red blood cell production, nutrient intake and absorption, and others. Symptoms of low hemoglobin include headaches, fatigue, fast heartbeat, and pale skin.

Treatments for low hemoglobin include iron supplements, iron therapy, blood transfusion, surgery, and treating the underlying condition causing low hemoglobin levels. Adding more iron-rich foods to your diet is also important if you have iron deficiency anemia.

If you have low hemoglobin, work with your healthcare provider to determine what is causing it and find a treatment plan to help you manage it.