The ads are enticing and hard to miss: A serene atmosphere featuring relaxed and beautiful people, all of whom ostensibly got that way by living the "spa" life.
In fact, from day spas to weekend spas to weeklong spa getaways, this form of "healthy" relaxation has become so popular that a 2006 survey by the International Spa Association (ISPA) reports one-quarter of all American adults - some 57 million folks - plus 4 million teens have had at least one visit to a spa.
Among the reasons cited: Stress reduction and relief, soothing sore joints and muscles, and simply feeling better about oneself. And experts say the survey findings doesn't surprise them.
"Going to a spa is a way of getting taken care of that is psychologically and culturally acceptable -- and we can carry that feeling of being cared for with us for a period of time, and very often that can help us cope better with stress," says NYU professor of psychiatry Virginia Sadock, MD.
Moreover, she says, most spa treatments involve being touched, a key element in helping us relax and feel better.
"Physical contact is necessary to our well-being, and even if the touching is from a stranger, if that stranger is a professional there to pamper you, that touch will have a beneficial effect," says Sadock.
And at least some studies show that these benefits can translate into better health. In one study of more than 3,300 Japanese government workers, frequency of spa use was linked to better physical and mental health, including better quality sleep and fewer sick days. In a similar study on German data conducted by researchers from Florida State University and George Mason University, spa therapy reduced both absenteeism from work and hospitalizations.
But are all spa treatments equal? And are there any hidden dangers that might prove unhealthy? WebMD discovered some surprising truths along the route to better health.
Spas: Are They Safe?
Who could forget the headlines that nearly wiped out the cruise ship industry: Hundreds of people stricken with Legionnaires' disease, a potentially deadly pneumonia traced to a heated spa whirlpool bath located aboard a luxury cruise ship.
Since that time, medical literature has been teeming with studies on similar situations, all indicating that communal pools, saunas, and other water-related spa treatments hold not only the potential to transmit this germ, but a host of equally threatening organisms.
"In many spa treatments that involve water, including hot whirlpool baths, very seldom do they change the water. They toss in some chlorine to keep bacteria counts down, but in no way does this eradicate organisms completely," says Philip Tierno Jr., PhD, director of microbiology at NYU Medical Center and author of The Secret Life of Germs.
And while he says some germs will succumb to chlorine, others, like those with a "biofilm" (a kind of molecular adhesive that binds several organisms together including those which cause Legionnaires' disease), it won't do a thing.
"You would need 1,500 times the amount normally used to kill it -- you would kill people before you would kill the organism," says Tierno.
And that, he says, means many spas can put you at risk. "It's not just heated pools and warm baths that are problem -- and it's not just Legionnaires' disease about which you should be concerned," he says. Other bacteria can also thrive in these conditions.
"These organisms love hot, wet environments -- spas are heated and steamy, and when you inhale vaporized water in this atmosphere you are potentially inhaling whatever organisms are present," he says.
Dermatologist Ellen Marmur, MD, says she's most concerned about risks to spa users seeking relief for skin problems, such as dermatitis or psoriasis. She says any break in the skin can increase the risk of germ transmission from surface areas like tables, baths, and even hot rocks or other items placed on the surface of the body during treatment.
"Even a bad sunburn can leave the skin compromised so that picking up an organism is easier," says Marmur. Moreover, she reminds us that some spa treatments such as full body exfoliation might actually increase risks further by creating microscopic tears in the skin that act as an invitation for germs to enter the body.
"When spa attendants don't wear gloves -- and most of them don't -- the risk of disease transmission is even greater," says Marmur.
Tierno says other risky spa treatments include manicures and pedicures, particularly if the cuticles are cut and especially if the instruments are not properly cleaned. Indeed, in the recent past an outbreak of a nasty bacterial infection causing skin boils was traced to unsanitary conditions in a manicure-pedicure salon.
"I always suggest bringing your own instruments. It's much safer than being treated with anything they supply," he says.
Spas: Can They Deliver Their Promises?
Among the biggest spa draws are the exotic treatment offerings -- and the equally exotic promises. From body rubs that attack cellulite, to lymphatic massages that promise to cleanse your body of toxins, to mud baths and anti-aging seaweed wraps guaranteed to soothe your skin and your psyche, the promises can go from the simple to the outrageous.
Assuming the spas take steps to prevent germ transmission, do any of the treatments themselves have risks? And do they even work? Experts say some do, and some clearly do not.
"As a dermatologist and a spa owner, I think that there is a place for some of the more exotic spa treatments. But does that mean that a caviar wrap from head to toe is going to transform you? No, just your wallet," says Ken Beer, MD, director of Palm Beach Aesthetics in Palm Beach, Fla.
Likewise, he says treatments that promise to banish cellulite offer, at best, a temporary change in skin texture and nothing more.
Marmur agrees. "What can happen is that the treatment causes swelling so the little spaces in between the dimples fill in. But the result is only temporary," she says.
A full body seaweed wrap may be another treatment to be cautious about.
Beer says seaweed wraps - with their high iodine content -- can be helpful to some folks and harmful to others. "Whatever you are applying to your skin can get into your bloodstream. ... If [iodine found in seaweed] is applied in high concentrations [it] may result in a nasty breakout on the skin, and other minerals can work the same way," he says.
Moreover, Sadock warns that some folks can get extremely claustrophobic in a full body wrap of any kind - and end up with an experience that is anything but stress reducing.
"Some people like the feeling of being cocooned or swaddled, and others feel like they have to get out - if you think you might feel that way, ask if the spa will leave your arms out of the wrap, which lessens the anxiety," she says.
Moreover, if you are the anxious type, Sadock suggests doing a walk-through or even observe treatments before you sign on for one.
"The one thing you don't want is for a treatment to increase your stress," she says.
Spa Treatments: What Works
While some spa treatments may do little, experts say others can do a lot. Among the ones frequently recommended by some doctors is the lymphatic draining massage.
"Lymphatic draining does help, particularly in areas that have been affected by surgery. Many of my patients that have had lymph nodes removed develop swelling that can be improved with lymphatic draining, which returns fluids back into circulation," says Beer.
In one small Italian study, doctors found that mineral water mud baths yielded a significant reduction in symptoms caused by psoriasis. A second study found mud baths offered promising relief for those suffering with osteoarthritis.
"The only thing to look out for is that psoriasis can flare from any trauma to the skin - so if the massage is rough, or the mud not well refined, it could actually make problems worse," she says.
But while it may be a specific spa promise that draws you in, experts say that for many folks the real value still lies not in the treatment itself, but in the pampering feeling that is universal to the spa experience.
Says Sadock: "The treatment is less important than the whole concept of being coddled - that's really what going to a spa is all about."