Q: In a dream, I recognized the perfume worn by a family member. How common is it to dream of smelling something?
“Surprisingly little” is known about dreams of smells and other sensations, according to a 1998 study, but a significant minority of subjects in the study reported dreams of scents.
The relatively small study, done in Canada and published in the journal Perceptual and Motor Skills, included 49 men and 115 women. Questionnaires and two to three weeks of morning diaries assessed their dreams. The subjects were not specifically asked to keep track of sensory dreams.
Among the 3,372 dream reports collected, sensations of smell or taste showed up in only about 1 percent.
In all, 25 subjects reported a total of 34 dreams of smelling something.
Smells showed up at least once in the reports from 2 percent of the men and 20.9 percent of the women. The authors conjectured that the imbalance might have arisen because women are more interested in odor than men are.
The researchers said the findings tended to confirm the results of previous studies of sensory dreams. But of eight such studies, six were very small, with reports from 13 people or fewer.
Tooth brushing details
Q: Why don’t we use hot water to brush our teeth?
There may be some reasons not to use hot or warm water, said Richard H. Price, a spokesman for the American Dental Association, but he added, “If I can get someone to brush their teeth, I don’t care what the water temperature is, as long as they don’t scald themselves.”
Price suggested that water that is too warm may soften toothbrush bristles, making them less effective, and that water that sits in a hot water tank or lead pipes may collect harmful substances.
Finding the right toothbrush can be daunting. “You need a Ph.D. to get through the dental aisle of confusion,” Price said, but he suggested simplifying the choice by looking for the ADA mark on the box, signifying that the bristles are firm enough to remove dental plaque but not hard enough to damage teeth or gums.
“Match the toothbrush to yourself, like dinnerware, so that it fits both hand and mouth,” he said. “In this case, size is important.”
After brushing, use hot water to rinse the brush, and let it dry thoroughly between uses. Change the brush every three or four months as the bristles fray.
And, he said, “Don’t brush without flossing.”
Brushing and flossing together do not kill the germs that colonize to form dental plaque, he said: “It just scatters them so they can’t reach critical mass” and cause tooth decay and gum disease.