Believers swear by aromatherapy, in which certain scents are supposed to have a positive effect on a person's mood or health.
But a recent investigation found that aromatherapy has no physiological effect on people at all.
The study concluded aromatherapy has no influence on your immune system, blood pressure, wound healing or pain control.
Lemon scent did seem to improve mood somewhat, but lavender did nothing. Even water showed more effect than lavender.
The study, published in Psychoneuroendocrinology, was conducted by Ohio State University.
On The Early Show Tuesday, Dr. Roshini Raj of New York University Medical Center explained that aromatherapy involves the use of "distinct, very concentrated scented oils" derived from plants and, "Supposedly, they have some health (or psychological) benefits."
The study, she says, was one of only a few to take "a very scientific look at aromatherapy," and focused on two commonly used scented oils, lemon and lavender. It found no benefit to wound healing, blood pressure, the immune system, or stress hormones. The only benefit seen was a positive mood move associated with the lemon oil, but not lavender.
The effect of lemon on mood "shouldn't be underestimated," Raj observed. "If we can actually just smell something and feel better, I think that's a pretty good thing!"
She added that a "very strong" placebo effect could be at work in people who think aromatherapy works, but there doesn't seem to be any real physical impact.
The study only looked at those two scents, she pointed out, because they're among the most commonly used in aromatherapy. Lemon is "supposedly a very stimulating, or activating scent, whereas lavender is more of a relaxing scent. They wanted to take contrasting scents."
However, Raj adds, they didn't seem to offer much benefit. If you happen to be feel less stressed and more positive with aromatherapy, she noted, it may help you deal with certain medical conditions.
It may also aid people who need help relaxing, Raj continued. Some pregnant women find aromatherapy with peppermint helpful, and lavender seems to help some with labor pain.
The study, Raj points out, was "relatively small," only involving about 50 people, "so you can't say aromatherapy doesn't work for everyone."
The bottom line: Aromatherapy can't hurt and is worth a try in some situations, but certainly shouldn't replace actual medications when they're needed.
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