Sniffing out the truth: Does scent therapy really have health benefits?

9/12/2023 5:00:00 PM | The Straits Times

The article is contributed/written by

Sniffing different scents, or olfactory training, has helped people regain their sense of smell after a Covid-19 infection. PHOTO ISTOCKPHOTO

SINGAPORE – Counsellor Sam Roberts often suggests that his clients apply a scented oil of their choosing to their hands before journalling their thoughts at the end of the day.

“The routine helps them process their moods and calms them down,” says the centre director and founder of private counselling practice Olive Branch Counselling and Therapy Clinic.

While he has long recommended journalling to clients with anxiety or depression, he began recommending the addition of scent only during the pandemic, when there was greater interest in the possible health benefits of scented oils.

Mr Roberts says it often helps older clients get into a better head space.

“I’m not sure how it works,” he says. “I don’t believe aromatherapy heals anything, but it definitely helps a lot with relaxation.”

Using scents and essential oils is widely believed to reduce stress and improve mental and physical health, even though scientific studies remain inconclusive.

Interest in aromatherapy began growing worldwide during the pandemic, according to United States-based consulting company Future Market Insights. It estimates that the aromatherapy market was worth US$5.9 billion (S$8 billion) in 2022 and will grow globally at 8 per cent a year, compared with 6 per cent growth until 2021.

The Future Market Insights report notes that this growth comes as more people use aromatherapy to relieve stress, improve sleep and alleviate anxiety. Some hospitals have also started using scent-related therapies in clinical settings.

Doctors and other healthcare professionals say scent-related therapies are being used in Singapore. However, they caution that there is a difference between what is used in clinical settings and what is popularly known as aromatherapy.

Dr Png Lu Hui, associate consultant at Singapore General Hospital’s department of otorhinolaryngology – head and neck surgery, explains that aromatherapy refers to the practice in which people sniff or apply scented oils and expect to receive health benefits based on the different properties of these oils.

“However, this is not usually standard clinical treatment for various medical conditions such as dementia, anxiety or depression,” he says.

He adds that there is limited scientific evidence that aromatherapy works to treat illness or disease. Researchers have investigated whether using scented oils can help with treating dementia or mood disorders, but results have been mixed.

What has been useful in the clinical setting is a therapy known as “olfactory training” or “smell training”. People who lost their sense of smell after a Covid-19 infection are made to sniff different scents, often lemon, rose, clove and eucalyptus.

This helps to regenerate or heal the olfactory nerves. “Many report an improvement in symptoms after this therapy,” says Dr Png.

Smell for well-being

Essential oils are generally safe to sniff, but doctors say to watch out for potential allergic reactions. PHOTO: ISTOCKPHOTO

Interest in the healing powers of scents stems from the fact that the sense of smell is important to one’s well-being and quality of life. Losing it can be both dangerous and upsetting.

Someone with a reduced sense of smell may be unable to detect odours from smoke or gas leaks, or may not be able to taste when food is spoilt. These pose safety risks, Dr Png says.

He adds: “Enjoyment derived from simple activities, such as eating and participating in hobbies, can be reduced by an impaired sense of smell, which can, in turn, affect our mood.”

Dr Soma Subramaniam, otorhinolaryngologist at Parkway East Hospital, says scent triggers memories and can be used in reminiscence therapy to connect with older people or those with Alzheimer’s disease.

“Smell is deeply intertwined with our culture, especially rituals such as those involving incense sticks,” he says. “This contributes to our sense of belonging and wellness.”

“The role of smell in regulating our overall well-being is only now beginning to be fully appreciated,” he adds.

The connection between smell and taste affects appetite and quality of life. Dr Soma recalls the case of a middle-aged woman who consulted him in late 2020. She had lost her sense of smell after contracting Covid-19 and broke into tears while discussing her condition.

“The emotional impact of her recent loss of smell was obvious,” he says. The patient had lost 3kg in two weeks because she had lost her interest in food, along with her sense of smell.

When no abnormalities could be detected in her nose via a nasal endoscopy or through magnetic resonance imaging, Dr Soma started the patient on olfactory training. Within three weeks, she had improved.

“She looked alive again. It was as though a part of her that was stolen was returned to her and made her whole again,” he says.

Doctors say essential oils such as those used in olfactory training are usually safe to sniff, but people should not ingest these oils. Precautions should also be taken before applying these oils on the skin.

Pregnant women should consult their doctors before using aromatherapy, according to Dr Soma, as some scented oils can cause hormone dysregulation.

“Any redness, itchiness, hives, or swelling of the skin should be warning signs to avoid exposure,” he says. Other symptoms to watch out for are itchy or watery eyes, a running nose or sneezing upon exposure to the oils.

Sniffing out dementia

Using scents and essential oils is widely believed to reduce stress and improve mental and physical health, even though scientific studies remain inconclusive. PHOTO: ISTOCKPHOTO

Scent and brain function are closely linked. The sense of smell can decline with age, and diseases such as Parkinson’s and Alzheimer’s often present with a significant decrease in the ability to smell.

Those who lose their sense of smell more rapidly are more likely to develop dementia, according to a University of Chicago Medicine study published in 2022 in medical journal Alzheimer’s & Dementia.

In 2023, the US’ National Institute on Aging published a study in the medical journal Neurology, showing that people who retained a better sense of smell as they aged were also more likely to have lower rates of cognitive decline.

So, could scent therapy protect against dementia or slow down its effects?

Doctors do not know yet. Dr Soma says: “While there is ongoing research on the role of olfactory training in managing dementia, results are variable. What is known is that scent therapy does enhance the ability to enjoy food, recognise familiar scents and engage in sensory experiences better, which will have a positive impact on people’s lives.”

Ms Samantha Tan, a senior occupational therapist with private nursing home Allium Healthcare, says scents can trigger memories and help her clients engage with their surroundings and caregivers.

At nursing home Allium Healthcare, cooking and baking release familiar smells, encouraging residents to share their memories. PHOTO: ALLIUM HEALTHCARE

When verbal communication is difficult, scents provide an alternative means of communication and stimulation.

At the nursing home, residents respond well to the use of essential oils and aromatherapy, and it regulates their blood pressure and heart rate, she says.

Supervised baking and cooking activities see clients respond to familiar scents.

When essential oils are used in group sessions with patients who have dementia, it reduces their agitation and other behavioural issues.

“I can affirm that scent therapy, or aromatherapy, has been beneficial in our practice,” says Ms Tan.

Scent and relaxation

An aromatherapy workshop at Scentopia in Sentosa, where participants create their own signature scents based on personality tests. PHOTO: SCENTOPIA

At local business Scentopia Singapore, which opened its physical space in 2022, more people are signing up for perfume-making workshops, where they create signature scents based on personality tests.

Founder Prachi Saini Garg and her team also offer team-building exercises based on aromatherapy. Groups of 30 to 40 come in for these, three or four days a week, though she once catered to 600 attendees at the same time.

“It’s a growing market,” she says. People enjoy the hands-on workshop, but are equally keen to learn about their scent preferences. Many realise that their preferred scent is not the same as the famous brand they have been using for years and the change is invigorating.

Scent and memory are intertwined, Ms Garg says. “Think of Tiger Balm or Vicks. The aromas don’t take away your pain, but they make you feel warm and happy. Maybe they remind you of your parents’ hands soothing you.”

Similarly, Mr Roberts thinks that essential oils might work to soothe his clients because they associate certain scents with happy or comforting memories.

An aromatherapy workshop at Scentopia in Sentosa, where participants create their own signature scents based on personality tests. PHOTO: SCENTOPIA

He does not sell or prescribe scents to his clients. The routine of using essential oils while journalling works with any kind of aroma, as long as the client likes it or finds that scent meaningful. For example, some like the scent of lavender and others prefer citrus. Mr Roberts has a soft spot for the aroma of sandalwood.

“Aromatherapy triggers neurotransmitters that tell the brain whether it is facing something dangerous, like a gas leak, or something pleasant,” he says.

A pleasant scent thus helps his client’s thoughts shift to a more positive plane. “The scent sends information to the brain and their thoughts immediately shift to, ‘Okay, this is safe.’ Their emotions become calm.”

He adds: “I don’t think of aromatherapy as a healing strategy, but as a distraction strategy. It’s distracting your mind from stress to focus on the smell.”