Scent therapy vs. “aromatherapy” for dementia: Smells can evoke powerful memories. But not all approaches are backed by science.
Familiar scents and odors spark powerful memories for just about anyone. Getting a whiff of freshly baked goods may bring someone back to their childhood, reminders of the chocolate chip cookies their grandmother may have made for them.
For decades, researchers have studied the link between familiar sensations, like scents, and the brain, including the link between scent and memory, and they’ve found that, indeed, therapy that relies on familiar smells may help some people relive good memories and boost their mood.
So, if a certain aroma can trigger past memories in cognitively healthy people, can it do the same for someone who has otherwise lost access to many of their memories — like a person living with Alzheimer’s or another form of dementia? Scientists say that in certain cases, yes: Scent therapy can be a helpful therapeutic tool.
But even though these terms are sometimes wrongly used interchangeably, don’t get scent therapy confused with aromatherapy. Aromatherapy involves diffusing essential oils like lavender or peppermint into the house. While some companies and practitioners make claims that being around these nice smells also boost memory, experts say there is no evidence that aromatherapy works.
What is scent therapy?
Scent-based therapy is a form of reminiscence therapy that uses familiar scents and odors to help people with dementia remember important memories from the past. This form of therapy is associated with a small but tangible reduction in anxiety and agitation and improvement in cognition and communication.
“I believe in our everyday life as we have conversations with older persons, including persons with mild to moderate dementia, engaging in reminiscing is pleasurable and worthwhile,” Dr. Erik B. Larson, a former investigator at Kaiser Permanente Washington Health Research Institute, wrote in an op-ed for Being Patient.
Practicing scent-based therapy doesn’t require buying expensive essential oils or diffusers. Instead, it can be as simple as taking loved ones with dementia to places they liked to go when they were young or helping them prepare or cook their favorite meals.
Spend enough time on Instagram or YouTube, you might get ads that send a whole different message: Buy some fragrant oils, diffuse them in the bedroom and living room, and bam, your memory will improve. That’s called aromatherapy… but beware, scientists say it doesn’t necessarily pack the same punch. And, there could even be some health risks attached.
What is aromatherapy?
Aromatherapy is a form of alternative medicine invented in 1937 by a French chemist named Rene-Maurice Gattefosse, who supposedly cured burns on his arm by using lavender oil, later studying the use of other concentrated plant oils — commonly called essential oils — for their wound healing properties. There was a lull in the popularity of aromatherapy until the 2000s.
Then, two companies, Young Living and DoTERRA, gained popularity while making unfounded medical claims and selling products through the multi-level marketing mode. On social media, they are promoted for everything from autism to dementia as a cure-all, bolstering the multi-billion dollar business of selling these plant extracts.
“The published evidence is sparse to nonexistent,” Dr. Harriet Hall wrote in Science Based Medicine. “There are clinical studies to support a few recommended uses, but they are generally poorly designed, uncontrolled, and unconvincing.”
Can aromatherapy boost memory and cognition?
Proponents of essential oils claim that diffusing certain scents into the air boosts memory and could potentially stave off dementia.
A recent, highly-publicized study found that diffusing these oils for two hours every night for six months boosted cognitive capacity by 226 percent in 43 cognitively healthy older individuals. Roughly half of the people in the study received an essential oil diffuser; the other half did not.
At the end of the trial, the researchers used a psychological test for memory where they read out 15 words, and participants were asked to repeat them back in any order. The researchers read out the same list to the participants five times, and only after the fifth trial did the people with the essential oil diffuser perform better than the control group.
This equated to a meager one-point difference on a psychological test, which would not translate to a noticeable difference in memory.
The study was funded by Procter and Gamble, which owns brands like Febreze, Olay, Ivory, Old Spice, and Herbal Essences. According to the press release that hyped up the study, they intend to release an essential oil product onto the market — using this study as “scientific proof” that it works.
Overall, scientists looking at the totality of the evidence across many of these trials don’t think there’s much of a case for essential oils.
Potential harms of aromatherapy
There’s nothing wrong with diffusing fancy oils for their scent. However, in the context of dementia, there is some potential for harm. Essential oils are highly flammable, trigger allergic reactions, and disrupt the body’s hormone-signaling system. In addition, diffusing essential oils can harm cats, dogs, and other furry family members.
Since they aren’t regulated like drugs either, there is no guarantee that the ingredients in the essential oil that someone is purchasing are accurate, and many products also overstate their benefits while downplaying potential risks.
Instead, it’s time to get scent-imental — find some inspiration from the UK Alzheimer’s Society. Scent-based reminiscence therapy is a safe and inexpensive way to connect with your loved ones and help them remember positive memories from their past.