A Life In Fragrance
How did you discover an interest in olfaction and the fragrance world?
I trained as a biological anthropologist which is the study of human biology within the context of culture, ecology and evolution. I started off by looking at human adaptation usually relative to climate change. I became really interested in olfaction, when I was teaching a class in evolutionary anthropology and wondered if our sense of smell might aid adaptation to new places, it only takes 2 synapses for odour information to get to the brain, which is shockingly fast compared to the other senses. It arrives first in the limbic region of the brain which also houses our emotions and memory.
The significance of this was highlighted for me when thinking about how prehistoric hunter gatherers might find new foods to eat when the environment is radically changed—such as during periods of glaciation. Smell is definitely important and can be the basis of decision-making. People smell their food before they eat it, especially if they are suspicious of it or if they want to enjoy it more. You can’t trust your visual sense and say ‘oh that berry looks like a good berry to eat’ because it could be poison or that mushroom could be poison even if it looks like one you’ve eaten before. I realised the sense of smell might play a role. That the rapid pathway to the limbic region of the brain evokes behaviour before you even have time to think about what it is you have smelt- I thought that was an obvious way we can use prior information to adapt to new environments, finding new foods etc. and it just took off from there. I began to get interested in genetic variation and how that might influence food preferences or even our ability to perceive an odour and its quality—variation in perception and hedonic valence of rose and jasmine for instance. I have always had a long-standing interest in perfume—scenting the body is an ancient practice and signifies how important we think odours are—for better as with perfumes and for worse as with toxic odours.
Is it just the olfactive sense you are interested in?
I am interested in the senses but in particular I’m interested in the sense of smell because it’s under-studied even though it is the most critical sense. The sense of smell is taken for granted, but as soon as someone loses it they suffer. Smell loss is linked to negative mental, physical and social health outcomes, such as depression and anxiety, weight gain or loss, and smaller social networks.
Talking of health issues, do you think it is possible to use smell in a diagnosis of health?
Most of the work in this area that I am aware of is focused on cancer—including cancer sniffing dogs and electronic noses. I read about a woman from Australia who claims to be a cancer smeller (with capabilities to smell cancer in someone). There is also an anecdotal evidence from hospitals and emergency staff including nurses that they can identify, by smell, common infections. Every nurse I’ve ever asked has confirmed "yep, we do that all the time". It’s a huge area that we need to be thinking about, because every disease emits an odour profile, or so it would seem, and identifying the common volatiles for that disease is the first step towards medical e-noses.
Have you noticed any diminishing in ability to smell as people age?
Yes, this is well-documented in western populations and often linked to cognitive decline and neurodegeneration. But, hunter gatherers don’t lose their vision or their hearing over time like we do. So, sensory senescence, might be lifestyle related—things like exposure to loud noises affects hearing and lack of natural light or too much time indoors during growth and development affects vision and causes myopia. Perhaps the built environments we live in and the
pollution we create are causing some of the problem—there is some interesting work on the linkages between smell loss and pollution.
I am currently studying olfactory ability in hunter gatherers to determine if their sense of smell remains acute over the lifespan like vision and hearing do. Maybe they are constantly interacting with the environment, smelling things, and using their sense of smell proactively so it remains intact. I suppose it is like in life, if you are constantly doing something then you improve at it.
As we are a technology focused generation, how do you think technology will impact our sense of smell going forward into a technology focused future?
I think it is an interesting area;
People with a diminished sense of smell or total smell loss usually have smaller social networks/isolated networks. Technology allows us to spend an increasing amount of time using virtual communication. But, communicating through technology does not allow the transmission of the odourless cues that indicate our emotional states to others. This might be having a larger effect on sociability than we currently understand.
Another area that is impacting us in regard to technology are the pollutants that technologies emit. Urban populations rely more on technology and the current global trend suggests that 61% of the human population will be in urban areas by 2030. While the use of technology is not directly linked to air pollution, the use of electricity is. Urban areas also suffer from higher rates of air pollution—mainly traffic emissions. There is evidence that urban populations suffer disproportionately from olfactory dysfunction and new arrivals will likely suffer the same fate. Where are we then? Will everyone have a diminished sense of smell?
There are cultures that are better engaged with their sense of smell. The more western you are, the more removed you are (or try to be) from smells. In countries with higher year-round temperatures, odours are a more natural part of life and not seen as a form of pollution. In some pastoral communities in Africa, the smells of their animals are pleasant—so pleasant they may use their urine to mark themselves. Meanwhile, in the west, some individuals have such an extreme aversion to odours that they seek to ban the use of scent in public! In the Andaman islands in India, the Onge use the odour of flowers to mark the passing of the calendar year. There are populations in Africa and Malay that use body odour as the basis of mating rules. So, there are traditional populations and post-industrial cultures that appreciate the odour scape and interact more deeply with it than we do. This lack of engagement might be the root of many of our problems!
If different cultures have a varying sense of smell, do you think the environment can alter someone’s ability to smell, or change the profile of a fragrance?
Charles Spence, known for his work in multi-sensory perception, works at Oxford.
One of his more interesting studies was asking the question why do we like a wine on holiday but not when we get home. We know that experience engages all the senses but he raises the idea that in the absence of some sensory stimuli, the presence of other stimuli is not adequate. In other words, the taste and smell of the wine you bring home from holiday are not sufficient to induce the same hedonic experience- in the absence of, for example, the waves crashing against the shore.
This is why I am interested in the environment. Why and how does the environment influence our sense of smell? Maybe, it is that these volatile compounds in your English garden and the botanicals there are blending with what you are drinking and smelling that is altering the profile of the wine. So, it’s not just that you’re not at the seaside and happy, but it might be that your environment is altering the aroma profile of the wine.
There is an increasing concern about the environment and pollution so it all ties together—the more plants you have to clean the air, the less pollution you have and the better your sense of smell. This will lead to the likely outcome that people will be happier and more engaged with their environments. Ultimately, we can better appreciate the natural odours around us as well as the created odours from perfumes!
What do you think the future of smell holds- how can we encourage people to use their sense of smell more, personally and professionally?
As much as people may say they would rather give up their sense of smell for some other commodity if forced to choose, they would miss it and suffer from its absence. I think there is a growing awareness of the importance of smelling. In the UK there is a charity called Fifth Sense who service the community of individuals with chemosensory disorders (taste and smell dysfunction). They have annual meetings and a growing national presence which suggests that people have been suffering without a support outlet for some time. In the past 10 years alone, there is a rise in companies creating a brand via a bespoke smell—even airlines use odours during long-haul flights to mark progress. I’ve noticed that when I’m travelling that I smell citrussy notes to wake you up and vanilla or lavender in the evening to help you go to sleep. There is an element already of smell-based marketing, particularly around the holidays. And, there are increasing products on the market for mood enhancement. There’s also more media interest in smell—olfactory research, bespoke smells, perfumes, olfactory art. People are increasingly interested in sensory experiences in leisure time—there’s a cocktail experience in London that asks you to smell vials as a basis for the bartender to determine what cocktail you will get! Right now it may be a niche interest—smell as a fun thing you can add into a computer game, a museum exhibit, or a way to get people involved in an event. Children obviously love smells and a multi-sensory experience never goes amiss. Overall, it is definitely a positive trend and I hope it continues so that people will become concerned about protecting their sense of smell while also becoming more engaged with it.