Q: I grew up thinking that people should take a shower every day because it's healthier. But is it that true?
A: For many — perhaps most — the daily shower is more about habit and societal norms than health. Perhaps that's why the frequency of bathing or showering varies so much from country to country.
Besides considering it healthier, people may choose to shower daily for a number of reasons, such as concerns about body odor, help waking up, or a morning routine that includes working out.
Each of these has merit, especially considering that personal or work relationships can be jeopardized by complaints about body odor or personal hygiene. When it comes to concerns about health, however, it's not at all clear that a daily shower accomplishes much. In fact, a daily shower may even be bad for your health.
Normal, healthy skin maintains a layer of oil and a balance of "good" bacteria and other microorganisms. Washing and scrubbing removes these, especially if the water is hot. As a result:
—Skin may become dry, irritated, or itchy.
—Dry, cracked skin may allow bacteria and allergens to breach the barrier skin is supposed to provide, allowing skin infections and allergic reactions to occur.
—Antibacterial soaps can actually kill off normal bacteria. This upsets the balance of microorganisms on the skin and encourages the emergence of hardier, less friendly organisms that are more resistant to antibiotics.
—Our immune systems need a certain amount of stimulation by normal microorganisms, dirt, and other environmental exposures in order to create protective antibodies and "immune memory." This is one reason why some pediatricians and dermatologists may recommend against daily baths for kids. Frequent baths or showers throughout a lifetime may reduce the ability of the immune system to do its job.
While there is no ideal frequency, experts suggest that showering several times per week is plenty for most people (unless you are grimy, sweaty, or have other reasons to shower more often). Short showers (lasting three or four minutes) with a focus on the armpits and groin may suffice.
If you're like me, it may be hard to imagine skipping the daily shower. But if you're doing it for your health, it may be a habit worth breaking.
(Robert H. Shmerling, M.D., is associate professor of Medicine at Harvard Medical School and Clinical Chief of Rheumatology at Beth Israel Deaconess Medical Center in Boston. For additional consumer health information, please visit www.health.harvard.edu.)