Recent Blog Articles
Monkeypox: An unfamiliar virus spreading fast — sound familiar?
Diabetes: Does a long-term study reinforce or change approaches to prevention?
War anxiety: How to cope
Can we prevent depression in older adults by treating insomnia?
Want to try veganism? Here's how to get started
Vitamin B6 flies under the radar: Are you getting enough?
The formula shortage is hurting families: What parents should know and do
Gyn Care 101: What to know about seeing a gynecologist
Swimming lessons save lives: What parents should know
Strong legs help power summer activities: Hiking, biking, swimming, and more
What Is It?
Anemia is an abnormally low level of red blood cells.
Red blood cells contain hemoglobin. Hemoglobin is a protein that carries oxygen in the blood.
To continue reading this article, you must log in.
Subscribe to Harvard Health Online for immediate access to health news and information from Harvard Medical School.
- Research health conditions
- Check your symptoms
- Prepare for a doctor's visit or test
- Find the best treatments and procedures for you
- Explore options for better nutrition and exercise
I'd like to receive access to Harvard Health Online for only $4.99 a month.Sign Me Up
Already a member? Login ».
As a service to our readers, Harvard Health Publishing provides access to our library of archived content. Please note the date of last review or update on all articles.
No content on this site, regardless of date, should ever be used as a substitute for direct medical advice from your doctor or other qualified clinician.
Free Healthbeat Signup
Get the latest in health news delivered to your inbox!