Can Sense of Smell Predict Future Heart Disease Risk in Older Adults?

A new study adds to a growing body of evidence that suggests your sense of smell isn’t just good for sniffing out the nearest bakery or warning you of something gross in your fridge — it’s also a surprisingly sensitive indicator of overall health.

The research found that older adults with a deteriorating sense of smell may be at higher risk of developing heart disease.

This finding, along with our other recent studies on sense of smell and the risk of stroke and heart failure, suggests a potential link between poor olfaction (the medical term for smelling) and heart health in older adults, says lead author Keran (Ada) Chamberlin, PhD, a postdoctoral researcher at Johns Hopkins University in Baltimore.

Sense of Smell Measured With ‘Sniffin’ Sticks’

Researchers used data from more than 5,000 adults who were 75 years old on average and participating in the Atherosclerosis Risk in Communities (ARIC) Study, a long-term project tracking heart health in U.S. adults.

Each participant took a 12-item “Sniffin’ Sticks” smell identification test, which uses pen-like devices infused with everyday odors including coffee, rose, banana, lemon, smoke, and cinnamon.

Test-takers were asked to identify each scent from multiple-choice options.

Scores were categorized as:

• Good olfaction: 11–12 correct
• Moderate olfaction: 9–10 correct
• Poor olfaction: 0–8 correct

Participants were then followed for nearly 10 years, and researchers tracked which ones were hospitalized for heart attacks or died from coronary disease.

People With Poor Sense of Smell Were Twice As Likely to Develop Heart Disease

After adjusting for other factors such as age, sex, race, and cardiovascular risk factors, researchers found that people with poor smell had close to double the risk of heart disease after the two- and four-year marks, compared with people with good smell.

But the predictive value diminished over the rest of the follow-up period: At six years, the extra risk declined to about a 60 percent increase, and at eight and nine years, the added risk was no longer statistically significant.

“The findings build on earlier work by the same group connecting smell loss to frailty, stroke, and mortality,” says Nicholas Rowan, MD, an otolaryngologist (ear, nose, and throat doctor) and researcher at Johns Hopkins Medicine who was not involved in the study.

Rowan finds it “particularly interesting” that the association between poor smell and heart disease was strongest in the first few years and then weakened.

That pattern supports the idea that smell loss may be an early sign — rather than a cause — of declining health, Rowan says. “It reinforces the concept that olfaction can serve as a window into overall physiological health,” he says.

Why Would Poor Smell Be a Warning of Future Heart Health?

While it’s not yet clear why the diminished capacity to smell might be a predictor of future heart disease, the authors put forth a few theories:

• Shared Blood-Vessel Problems Our sense of smell relies on a steady blood flow to the nose; blood flow can be compromised in the early stages of heart disease due to inadequate blood supply.
• Lifestyle Effects A dulled sense of smell can lead to less interest or pleasure in eating, which can negatively impact older adults' diet and nutrition, mood, physical activity, and social health — thereby jeopardizing heart health over time.
• Frailty Connection Emerging evidence links a poor sense of smell to frailty in older adults, offering another potential pathway to cardiovascular problems. In medical terms, frailty means that you are vulnerable and the body isn’t able to handle more strain from illnesses or injuries.

Is Loss of Smell Just a Normal Part of Aging?

Some decline in smell sensitivity is common with age, and can also happen due to chronic sinus issues, allergies, smoking, or certain medications. Older adults may also experience taste and smell changes that reduce appetite, leading to poor nutrition and weight loss.

Should Sense of Smell Be Used as a Screening for Future Health Issues?

The uncertainty about why or how smell loss relates to heart disease doesn’t take away from its clinical importance, says Rowan.

“In my view, this study adds weight to the argument that routine smell testing in older adults could be a useful and inexpensive way to identify individuals who may be at higher risk for broader health decline, even if we do not yet have clear interventions for smell loss itself,” he says.

Even though smell testing is simple, inexpensive, and noninvasive, it’s rarely done outside research settings, says Rowan.

“As we learn more about how sensory decline reflects systemic health, routine smell screening in older adults could become a valuable tool for early risk identification, similar to how we use blood pressure or cholesterol testing today,” he says.

What to Do if You Notice Changes in Your Sense of Smell

“Most of us still do not pay attention to our sense of smell,” says Chamberlin.

Although smell loss is common in older adults, the majority of those affected don’t recognize the deficiency when asked, she says.

Chamberlin suggests that older adults would benefit from paying more attention to their sense of smell, and talk to their primary healthcare provider if they notice an unexplained and persistent loss.

“Work with them to identify potential causes and discuss ways to address potential health concerns,” she says.