The Call-On-Doc Guide to Anemia

Feeling tired all the time is common—National Sleep Foundation polling found many Americans report frequent daytime sleepiness, including those who feel sleepy most days of the week.
But persistent fatigue isn’t always “just life.” If you’re sleeping adequately and still feel drained—or you’re noticing symptoms like dizziness, shortness of breath with routine activity, paleness, or rapid heartbeat—anemia is one possible cause worth checking.

Call-On-Doc can help you start with basic screening labs like a Complete Blood Count (CBC), which is a key first step in evaluating anemia. A CBC helps identify low hemoglobin/hematocrit and changes in red blood cell size that point toward likely causes (such as iron deficiency vs. B12/folate deficiency).

Anemia is common. The American Society of Hematology notes that the National Heart, Lung, and Blood Institute estimates anemia affects more than 3 million Americans.
Severity ranges from mild (often found incidentally on labs) to severe (can strain the heart and reduce oxygen delivery). Anemia can become serious if it’s caused by ongoing blood loss, significant nutrient deficiency, kidney disease, inflammation, or an underlying condition that needs treatment.

A recent CDC/NCHS data brief estimated anemia prevalence around 9.3% of the U.S. population age 2+ (Aug 2021–Aug 2023), underscoring how common it is.

Symptoms depend on the cause and how quickly anemia developed. Some people have no symptoms; others may experience:

• Fatigue, low stamina, weakness

• Shortness of breath with activity

• Dizziness/lightheadedness or headaches

• Paleness (skin or inner eyelids), cold hands/feet

• Fast heartbeat or palpitations

• Chest discomfort (more urgent)

Seek urgent care now if you have chest pain, fainting, severe shortness of breath, black/tarry stools, vomiting blood, or symptoms of severe weakness—especially if sudden.

La anemia ocurre por tres razones principales:

1. Producción insuficiente de glóbulos rojos (deficiencia de hierro/B12/folato, inflamación, enfermedad renal, problemas de médula ósea)

2. Pérdida de sangre (menstruaciones abundantes, sangrado gastrointestinal, cirugía/trauma)

3. Destrucción acelerada de glóbulos rojos (hemólisis, causas autoinmunes o hereditarias)

Las mujeres tienen mayor riesgo de deficiencia de hierro por pérdidas menstruales y por el aumento de requerimientos en el embarazo.
En hombres y mujeres posmenopáusicas, la anemia por deficiencia de hierro suele requerir evaluación para descartar sangrado gastrointestinal oculto.

Causes of Anemia

According to the Office of Women’s Health, women can be more prone to certain types of anemia. As will be mentioned in the section below, blood conditions like iron deficiency anemia add to the difficulty of menstrual cycles and pregnancy. 

By comparison, the same blood condition is rarer in men, as reported by Live Strong. Most men who do have it report feeling none of the symptoms, while those who have either experienced blood loss or subsist on a diet without meat. 

In most other examples of anemia, each type is equal between men and women. Here are some of the best-known examples of anemia at the time of writing.  

A CBC is the starting point, but identifying the type usually requires additional tests guided by your results and symptoms, such as:

• Ferritin + iron studies (iron deficiency vs. inflammation)

• Vitamin B12 and folate

• Reticulocyte count (marrow response)

• Kidney function tests

• Inflammation markers (in some cases)

• Tests for hemolysis or inherited disorders when indicated

Common examples:

• Iron deficiency anemia (most common)

• B12/folate deficiency anemia

• Anemia of chronic disease/inflammation

• Hemolytic anemia

• Aplastic anemia (rare, serious)

• Sickle cell disease and thalassemia (inherited)

CDC notes sickle cell disease affects about 100,000 people in the U.S.

Consider evaluation and labs if you have:

• Fatigue that persists despite adequate sleep

• Shortness of breath with routine exertion

• Dizziness, frequent headaches, palpitations

• Pale skin, brittle nails, unusual cravings for ice (pica)

• Heavy periods or any signs of bleeding

• Symptoms plus unintended weight loss, fevers, or night sweats

Treatment depends on the cause:

• Iron deficiency: dietary changes + iron supplementation; treat the source of blood loss

• B12/folate deficiency: supplementation; evaluate absorption issues

• Chronic disease anemia: treat the underlying condition

• Kidney disease anemia: may involve iron and/or erythropoiesis-stimulating therapy

• Severe anemia: may require urgent interventions (and, in some cases, transfusion)

Prevention focuses on risk reduction:

• Eat iron-rich foods (meat, beans/lentils, leafy greens) and pair plant iron with vitamin C

• Ensure adequate B12 (especially if vegetarian/vegan) and folate intake

• Address heavy periods with a clinician

• Avoid self-treating long-term fatigue with supplements without testing—too much iron can be harmful if you don’t need it

If you’re concerned about anemia, Call-On-Doc can help you:

• Discuss symptoms and risk factors

• Start with screening labs (like CBC)

• Review results and recommend next-step testing or referral when needed