Taking a daily shower is as common as drinking a cup of morning coffee and brushing your teeth, but it’s a habit that could be worth breaking, experts say.

Some two-thirds of Americans shower every day. People say their daily showers help them wake up and keep them clean, especially following exercise or exertion or in hot and humid weather.

“When it comes to concerns about health, however, it’s not at all clear that a daily shower accomplishes much,” said Dr. Robert Shmerling, clinical chief of rheumatology at Beth Israel Deaconess Medical Center at Harvard Medical School and faculty editor at Harvard Health Publishing.

“In fact, a daily shower may even be bad for your health.”

Washing and scrubbing removes the skin’s oil and healthy bacteria, and it can become dry, irritated and itchy.

This is particularly true among older people, whose skin grows thinner, less hydrated, and more sensitive. Dry, cracked skin can allow bacteria to get through, causing infections and allergic reactions.

“I think showering is mostly for esthetic reasons,” says Dr. Elaine Larson, an infectious disease expert and associate dean for research at Columbia University School of Nursing.

“People think they’re showering for hygiene or to be cleaner, but bacteriologically, that’s not the case.”

Showering can break down the skin’s acid mantle, its natural protective barrier, leaving it vulnerable to bacterial and viral invasion.

“The skin is stripped of natural oils and protective organisms,” said Dr. Jennifer Herrmann, a Beverly Hills dermatologist.

“This leads to dryness and can exacerbate many skin conditions from eczema to rosacea to psoriasis.”

Also, some doctors say the human immune system needs a certain amount of exposure to microorganisms and dirt to create protective antibodies, and frequent showers over time could be contributing to allergies, asthma, autoimmune diseases and even diabetes.

“Your body is naturally a well-oiled machine,” said Dr. Brandon Mitchell, assistant professor of dermatology at George Washington University. “I think most people over-bathe. A daily shower isn’t necessary.”

Mitchell suggested showering or bathing once or twice a week, and experts generally say a few times a week rather than daily is plenty.

Also, keep showers short and lukewarm, as too much water, particularly hot water, dries out the skin.

Showering less often in winter makes sense, Herrmann noted.

“In the winter months, when air is drier and indoor heaters are in full force, the skin tends to be more dry,” she said. “Too frequent showering worsens dryness and flares skin conditions.”

Harder than it sounds

Keep showers short and lukewarm, as too much water, particularly hot water, dries out the skin.

Giving up that daily shower might not be so easy.

“It has become an essential and not an optional thing to do,” said Elizabeth Shove, a sociologist at the U.K.’s University of Lancaster who researches water consumption practices.

“Why is it that so many people today pour so many liters of water over themselves to remove just a few specks of dirt, and why do so many do so on such a regular basis?

“When you think about it, it really is very strange,” she said.

How often should you wash your hair?

How many times a week do you think you should wash your hair? Every day? Every other day? According to trichologists, the technical term for health professionals who specialize in hair and scalp, that’s way too often.

“Someone with thin, fine or delicate hair should avoid shampooing too frequently — no more than two times a week — should help maintain the natural oil production, while achieving moisture balance,” says Andrea L. Hayden, Director of the International Association of Trichologists (USA) and owner of The Hair Management Group in San Antonio, TX.

And if you have coarse or curly hair, try once every seven days. “Coarse texture or natural curly hair takes longer to establish a good amount of natural oils, so shampooing can be pushed back to once a week. A person could refresh the hair/scalp mid-week, if necessary, by simply applying a conditioner and rinsing thoroughly.”