The Blueme Smell Test is a self-administered smell assessment designed to support everyday smell health awareness.

Most people have never tested their sense of smell. Unlike vision and hearing, it is not part of a routine check-up — and yet it is one of the earliest changes the body reports.

Blueme holds Institutional Review Board approval for a research study evaluating how people use and experience the Blueme Smell Test. Founder and CEO Mei Xu is Principal Investigator. The study assesses adults between the ages of 18 and 80 in real-world and home settings.

Mei Xu was the first industry leader invited to the inaugural symposium of the NIH National Smell and Taste Center, alongside researchers from Harvard, the University of Pennsylvania and the University of Dresden.

Olfactory training is a structured practice of repeated, deliberate exposure to a set of distinct scents over a sustained period. It is used to support the recovery of olfactory function after loss.

Blueme is developing a training program built on this protocol, designed to be followed at home and supported by the same fragrances used in daily practice.

Smell is the only one of the five senses wired directly to the limbic system, the part of the brain that governs memory and emotion. The other senses route through the thalamus first. Scent does not.

That direct pathway is why a single note can return you to a room you have not stood in for thirty years, and why fragrance reaches feeling before it reaches thought. It is also why fragrance can be built deliberately, for a purpose, rather than only for pleasure.

Close your eyes. Let a single note carry you.

A kitchen you have not stood in for thirty years, warm with something simmering. The paper bag where your grandmother dried her herbs. Incense drifting through a temple you visited once and never forgot. You did not choose to go there. You were given no time to choose. The scent gathered you up and took you.

Marvel at what has just happened. Smell is the only one of your five senses wired directly into the limbic system — the ancient seat of memory and emotion. Your other four senses wait their turn at the thalamus, where the mind sorts and names and files. Scent is granted no such patience. It arrives ahead of thought, ahead of language, ahead of anything you have decided.

This is why fragrance reaches your heart before it reaches your mind. And it is why a fragrance can be composed with purpose, and not for beauty alone.

Now travel that road in the other direction, where something quieter waits.

The delicate tissue that carries scent to you sits close beside the regions of the brain that neurodegenerative disease reaches first. So when your sense of smell begins to change, the body has already spoken — long before it will say anything else. Olfactory dysfunction is associated with more than 130 medical conditions. In Alzheimer’s and Parkinson’s it often arrives years ahead of the first symptom anyone thinks to notice.

Before the pandemic, some degree of smell loss was thought to touch a fifth of all adults. Almost none of them knew.

Researchers at the University of Chicago tested 515 older adults once a year, some for as long as eighteen years, on three things: whether they could identify a set of smells, how well they were thinking, and whether dementia had appeared.

What mattered turned out to be speed. Not whether a person’s sense of smell was weak, but how quickly it was fading. Those whose smell fell away fastest, while their thinking was still entirely normal, were the most likely to be diagnosed with Alzheimer’s or mild cognitive impairment in the years that followed.

Among the participants who also received brain scans, those same people had less gray matter in the regions that handle smell and memory. Gray matter is the working tissue of the brain — the cell bodies themselves, where thinking and remembering are done. It is not a passage that carries signals from one place to another; it is the place the work happens. So having less of it is a loss, and it is one of the earliest physical marks Alzheimer’s leaves behind.

The size of that risk was comparable to carrying APOE-ε4, the best-known genetic risk factor for Alzheimer’s.

The study has limits worth stating. Its participants averaged 76 years of age and nearly all were white, so the finding needs repeating in other populations. And it shows a link, not a cause. But what it says is plain enough: a sense of smell that is slipping quickly deserves your attention.

In 2026, six of the world’s leading researchers in olfaction searched the public health agendas of nations and found smell missing from every one. The sense left behind by sight and hearing, they called it. Their recommendation was unadorned: begin screening.

Our founder is a co-author of a second review from that same year, published in Frontiers in Allergy alongside scientists of the NIH National Smell and Taste Center, on how that screening should be done.

That review draws a line, and we keep faithfully to it. A brief test screens — it tells you only whether something deserves a closer look. A full diagnostic battery is another instrument altogether, and it belongs in a clinician’s hands.

Blueme stands on the screening side of that line, gladly. Our fragrances are not medicine. Our smell test is not a diagnosis. What we build comes before a doctor, never instead of one.

Therapy is the daily practice. Testing is the measure. Training is the way home.

Come and begin.