Why She Smells It and He Doesn’t

Have you ever noticed a musty smell in a basement—or even in your own home—while someone standing right next to you says, “I don’t smell anything”?

There may be a scientific reason for that.

Research has consistently found that women, on average, perform better than men at detecting, identifying, and distinguishing odors. A large meta-analysis published in Frontiers in Psychology confirmed this female advantage across several different measures of the sense of smell.

Why? Researchers believe there are several factors involved, including differences in the brain and the influence of sex hormones. Estrogen and testosterone both interact with the olfactory system. Some research has suggested that testosterone may decrease sensitivity to certain odors, although the relationship between hormones and smell is complicated and scientists have not established that testosterone universally suppresses the sense of smell.

We have an interesting real-world example of this from our own field.

One experienced female mold inspector had an exceptionally keen sense of smell. In fact, her nose was a valuable tool during mold inspections. She could often detect a musty or unusual odor immediately upon entering an area.

Later, she was prescribed testosterone therapy because of muscle loss. After beginning testosterone, she noticed something remarkable: her sense of smell had drastically diminished.

That is only one person’s experience, so we certainly can’t say that testosterone was proven to be the cause. But it is an interesting anecdotal observation considering what researchers have discovered about the relationship between reproductive hormones and our sense of smell.

But Sometimes It Isn’t About Whether You Smell It

There’s another fascinating part of this that we’ve noticed after years of investigating homes: two people may actually smell the same thing but interpret it differently.

During one basement inspection, a husband told us that he couldn’t smell mold. His wife, however, clearly could.

So instead of asking him again whether he smelled mold, I asked him a different question:

“Do you smell wet dirt down here?”

“Yes,” he replied.

That changed the conversation. He was detecting an odor. He simply wasn’t identifying it as a mold or musty odor.

Over the years, we’ve heard men describe odors in mold-affected environments as dirt, wet wood, earthy, damp, or an old-basement smell, while women may describe a similar odor as musty or moldy. That’s our observation from the field—not a scientifically established rule about men and women—but it demonstrates something important.

Our sense of smell isn’t just about what reaches our nose. The brain also has to recognize the odor, associate it with previous experiences, and decide what to call it.

That’s why, during an environmental investigation, asking someone “Do you smell mold?” may not be the best question.

Sometimes a better question is simply:

“What does it smell like to you?”

The answer may tell us much more.

So, if one person in your family keeps saying that something smells musty and everyone else thinks they’re imagining it, don’t dismiss them. Their nose may actually be picking up something yours isn’t—or you may both be smelling the same thing and simply describing it differently.

Martine Davis, BBEC

Indoor Environmental Testing, Inc.
We detect what you suspect.

Scientific references:
Sorokowski, P., et al. (2019). Sex Differences in Human Olfaction: A Meta-Analysis. Frontiers in Psychology, 10, 242.

Doty, R. L., & Cameron, E. L. (2009). Sex Differences and Reproductive Hormone Influences on Human Odor Perception. Physiology & Behavior, 97(2), 213–228.