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Does mouthwash affect your immune system?


The antibacterial triclosan cleans the mouth, but may have a larger negative impact on the immune system.
The antibacterial triclosan cleans the mouth, but may have a larger negative impact on the immune system.
© Stephen Welstead/LWA/Corbis

We live in a society obsessed with cleanliness. It seems as if we frequently wash, wipe down and sanitize everything in our homes and on our bodies. This collective concern over germs does have its benefits – it helps stop the spread of bacteria and viruses, and doing so keeps us healthy. Consider how hand washing minimizes the spread of disease, or how tooth brushing improves oral health.

Despite these important advantages, we may be overdoing it a bit. Some scientists believe we actually weaken our body's defenses by staying so clean. A few germs here and there actually give the immune system a chance to build its muscles, so to speak.

Imagine your immune response as a castle guard. When the guard faces a throng of invaders, he may be ill equipped to fight back if he's only ever had to confront a handful. If, however, he's experienced at regularly fending off numerous foes, he'll be better prepared for a large group. The human immune system is similar in that it needs to remain practiced and prepared [source: Lang-Cornell].

There are other ways we may hamper our immune systems. Using certain antimicrobial (germ-fighting) products can sometimes cause an overactive immune response.

One particular antimicrobial that has some medical experts concerned is triclosan, an ingredient found in some mouthwashes. (It also turns up sometimes in toothpaste and hand soap.)

Johns Hopkins University researchers found that children with high levels of triclosan were more likely to have high levels of immune chemicals, similar to those found in people with allergies. Studies have also indicated that triclosan might contribute to antibiotic resistance [source: Steckelberg]. Consequently, many manufacturers are removing triclosan from products that once contained it.

If you're worried about this ingredient, make sure you check the label on your mouthwash and other personal products before you purchase them.

Learn more about oral care and the immune system and get lots more information on the next page.


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