1. It Helps Filter Blood
Think of the spleen as the immune system’s best supporting organ. “Its main job is to filter blood, and it also filters certain bacteria from our blood stream,” says Vaidya. The cashew-shaped organ, which measures about the size of a fist, clears out bad bacteria that can cause infections like pneumonia and meningitis.
2. It’s Not as Dispensable as Doctors Once Believed
“Until a few years ago, we thought it was a completely vestigial organ and that there wasn’t much use to it,” says Vaidya. “Now we know there is use for the spleen.” One relatively recent discovery is the spleen’s role in producing red blood cells early in life. “As we grow older, that function is taken over by the bone marrow and the spleen takes a backseat, but it does play a critical role in immunity,” says Vaidya. A 2009 study published in Science found the spleen stores cells called monocytes, which come in handy when your body is fighting infection or repairing tissues.
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3. Still, You Can Live Without It
Some people have their spleen removed because of an accident, a blood disorder, or a blood-affecting cancer like leukemia. Luckily, it’s not an essential organ like the heart or liver, and living spleen-free is doable—so long as you take the appropriate precautions. You’ll just need to receive immunizations for the bacteria the spleen usually guards against in order to stay healthy, says Vaidya. Doctors recommend getting the pneumococcal vaccine, which protects against bloodstream infections, pneumonia, and meningitis after your spleen is removed, with booster shots every three to five years.
4. An Enlarged Spleen Could Signal Other Health Issues
The spleen becomes problematic when it grows in size. That could be a tipoff that some underlying problem is going on, such as mononucleosis or a blood condition like leukemia or lymphoma. An enlarged spleen in and of itself could also put you at risk since it’s prone to rupture, says Vaidya. That usually happens as a result of an accident or an intense sports game and can lead to dangerous internal bleeding.
5. But It’s Tough to Know if Your Spleen Has Gotten Too Big
“It may only be found when you’re in a doctor’s office for an exam or if you have scans for another reason and the scan picks up an enlarged spleen,” says Vaidya. That said, there are some clues, like pain on your left side (the result of the spleen pressing against your stomach), unexplained weight loss, queasiness, and nausea. Only when you feel sharp stabbing pain on your left side should you consider it an emergency. Otherwise, visit your doctor for a basic evaluation.
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6. Some People Have an Extra One
And the hottest accessory of the season is…an accessory spleen, or an extra, smaller spleen that many people have. One study published in the Malaysian Journal of Medical Sciences found nearly 20 percent of the 334 hospital patients they looked at have one—and 40 percent of the people in that group have more than two. Not to worry: It won’t affect your health, though it can be mistaken for a tumor.
7. What Keeps Your Liver Healthy Will Protect Your Spleen, Too
To keep your spleen in tip-top shape, adopt some of the same practices you’d follow for a healthy liver: Drink alcohol in moderation, don’t exceed Tylenol doses beyond what is prescribed, and practice safe sex to protect against hepatitis, says Vaidya.