Anemia risk factors: who is more likely to get anemia

What anemia is

Anemia develops when your blood has a lower-than-normal amount of healthy red blood cells, so your body does not get enough oxygen-rich blood (NHLBI). Red blood cells contain hemoglobin, an iron-rich protein that carries oxygen from your lungs to the rest of your body (NHLBI).

Anemia has three main causes: blood loss, too few red blood cells being made, and red blood cells being destroyed too fast (MedlinePlus). There are many types, including iron-deficiency, vitamin B12-deficiency and hemolytic anemia. The most common type is iron-deficiency anemia (NHLBI). Mild anemia is common, treatable and can develop in anyone; some types are inherited (NHLBI).

Risk factors

Some causes of anemia cannot be changed, like family history or age. Others can be managed, like eating habits or other health conditions (NHLBI). NHLBI lists (NHLBI):

• Age. Your chances of anemia go up as you age.
• Blood loss. Any condition that makes you lose a lot of blood raises your risk. This includes bleeding from inflammation in the stomach or bowels, surgery, a serious injury, or donating blood often.
• Heavy periods. Anemia from heavy menstrual bleeding is not normal. NHLBI says to see your doctor if you need to change your tampon or pad after less than 2 hours, or you pass clots the size of quarters or larger.
• Family history of inherited types of anemia.
• Not getting enough iron, vitamin B12 or folic acid, the nutrients your body needs to make healthy red blood cells.
• Drinking too much alcohol.
• Other health conditions: chronic kidney disease, inflammation from an infection, cancer, or an autoimmune disease can make your body make fewer red blood cells.
• Certain medicines or treatments, such as chemotherapy for cancer.

MedlinePlus adds pregnancy, ulcers, colon polyps or colon cancer, blood disorders such as sickle cell anemia and thalassemia, aplastic anemia, and G6PD deficiency to the list of conditions that may lead to anemia (MedlinePlus). Anemia can also be a sign of a more serious condition, such as bleeding in the stomach, kidney disease, cancer or an autoimmune disease (NHLBI). See kidney disease risk factors and colorectal cancer risk factors.

Iron-deficiency anemia risk factors

Your body needs iron to make healthy red blood cells. NHLBI lists these as raising the risk of iron-deficiency anemia (NHLBI):

• Blood loss: bleeding in the stomach or intestines (for example from inflammatory bowel disease, an ulcer or colon cancer), injuries or surgery, heavy periods or bleeding during childbirth, regular use of aspirin or NSAIDs such as ibuprofen and naproxen that can lead to bleeding in the gut, and urinary tract bleeding.
• Problems absorbing iron: celiac disease, ulcerative colitis, Crohn's disease, Helicobacter pylori infection, surgery on the stomach and intestines including weight-loss surgery, some rare genetic conditions, and endurance sports.
• Other conditions: kidney disease, and long-lasting conditions that cause inflammation, such as congestive heart failure or obesity.
• Young children who do not get enough iron in their diet, usually between 9 months and 1 year of age as they move to whole foods.

Anemia in pregnancy

Anemia, especially iron-deficiency anemia, is common during pregnancy, because your body makes more blood to support the baby and needs more iron and other nutrients. NHLBI says all women are at risk for anemia during pregnancy, and doctors do blood tests to check for it at different stages (NHLBI). Serious or untreated anemia in pregnancy can lead to preterm labor, more blood loss during delivery, low birthweight, and anemia and developmental delays in the baby (NHLBI).

Routine iron screening and supplements in pregnancy are a separate question; the iron deficiency in pregnancy check covers what the USPSTF says about them.

Signs of anemia

Mild anemia may cause no symptoms. Symptoms can develop quickly or slowly depending on the cause. Common ones include (NHLBI):

• weakness, tiredness and paleness
• chills
• shortness of breath
• headache
• dizziness and fainting

More serious iron-deficiency anemia can also cause chest pain, cold hands and feet, and pale skin (NHLBI). Doctors diagnose anemia with a physical exam and blood tests (MedlinePlus).

Common questions

Can anemia be prevented?

Some types can. Your doctor may suggest more foods rich in iron or vitamin B12, such as leafy vegetables, meat, milk and eggs, or supplements. If you are a strict vegetarian or vegan, ask your doctor how to get all the nutrients you need. Anemia caused by your genes cannot be prevented; if you have an inherited type and plan to have children, a genetic counselor can explain the risk and your choices (NHLBI).

Which foods help with iron?

NHLBI lists beans, dried fruits, eggs, lean red meat, salmon, iron-fortified breads and cereals, peas, tofu and dark green leafy vegetables as good sources of iron, and says vitamin C-rich foods such as oranges, strawberries and tomatoes help your body absorb it (NHLBI).

Should I just start taking iron pills?

Talk to your doctor first. Treatment depends on the type of anemia you have (MedlinePlus), and anemia can be a sign of another condition, such as bleeding in the stomach, that needs to be found (NHLBI).

Also see gestational diabetes risk factors, preeclampsia risk factors and screening tests by age.