Even though most adults want to avoid looking older than their actual age, research led by St. Michael's Hospital shows that looking older does not necessarily point to poor health. The study found that a person needed to look at least 10 years older than their actual age before assumptions about their health could be made.

"Few people are aware that when physicians describe their patients to other physicians, they often include an assessment of whether the patient looks older than his or her actual age," says Dr. Stephen Hwang, a research scientist at St. Michael's Hospital and an associate professor at the University of Toronto. "This long standing medical practice assumes that people who look older than their actual age are likely to be in poor health, but our study shows this isn't always true."

For patients, it means looking a few years older than their age does not always indicate poor health status. The study found that when a physician rated an individual as looking up to five years older than their actual age, it had little value in predicting whether or not the person was in poor health. However, when a physician thought that a person looked 10 or more years older than their actual age, 99 per cent of these individuals had very poor physical or mental health.

"Physicians have simply assumed that their quick assessment of how old a person looks has diagnostic value," explains Dr. Hwang. "We were really surprised to find that people have to look a decade older than their actual age before it's a reliable sign that they're in poor health. It was also very interesting to discover that many people who look their age are in poor health. Doctors need to remember that even if patients look their age, we shouldn't assume that their health is fine."

The researchers studied 126 people between the ages of 30 to 70 who were visiting a doctor's office. Participants completed a survey that accurately determined whether they had poor physical or mental health. Each person was photographed, and the photographs were shown to 58 physicians who were told each person's actual age and asked to rate how old the person looked.

The study, published in the Journal of General Internal Medicine, provides new insights and questions into the value and limitations of a long standing medical practice of judging a person's health by how old they appear.