Developments in Brief : In a Sniffing Contest, Researchers Would Place Their Bets on Women

The sense of smell is duller in the morning, keener at night. But whatever time of day, women have a better sense of smell than men, according to two researchers who have different theories to explain the olfactory discrepancy between sexes.

Robert Henkin of Georgetown University believes that smell sensitivity is linked to hormone levels in the body. But William S. Cain of Yale says the explanation may be that such sensitivity is affected by training and that women have been cooking and buying perfume a lot longer.

Henkin, director of Georgetown’s Center for Molecular Nutrition and Sensory Disorders, tested six women to see how closely their sense of smell is linked to ovulation. For six weeks he measured the women’s ability to sniff out two unpleasant odors (skunk and dead fish) and two pleasing fragrances (banana oil and almonds). At the same time, he monitored basal body temperature and hormone levels to determine ovulation.

It turned out that when ovulation occurs and estrogen levels rise, olfactory sensitivity soars--up to 1,000-fold. Henkin said his findings suggest a hormonal basis--and possible link to reproduction--for women’s overall olfactory gifts.

In Cain’s tests, which involved 20 subjects of both sexes, women out-sniffed men even on “male smells” like cigar butts. But Cain theorized that memory and women’s verbal skills, not just hormones, give them the edge. If people can correctly label and encode a smell, the chances of identifying it later are better, he said.