MIAMI (AFP) - When it comes to being healthy in one's older years, age means little and obesity may not be so bad after all, according to a American study released on Monday.
Instead, researchers at the University of Chicago found that factors such as loneliness, depression and having broken a bone recently are more likely to predict a person's risk of dying in the next five years.
"Instead of policies focused on reducing obesity as a much lamented health condition, greater support for reducing loneliness among isolated older adults or restoring sensory functions would be more effective in enhancing health and well-being in the older population," said co-author Edward Laumann, professor of sociology at the University of Chicago.
The study in the Proceedings of the National Academies of Science involved 3,000 people aged 57 to 85.
"The healthiest people were obese and robust," said the study, which found that 22 per cent of older Americans fit this definition of being in good health despite higher obesity and blood pressure.
They had fewer organ system diseases, better mobility, sensory function, and psychological health than others.
They were also the least likely to die or become incapacitated five years into the study.
Researchers also uncovered new classes of people who faced twice the risk of dying or becoming incapacitated in five years - those who were normal weight but faced one key health problem such as thyroid disease, anemia or ulcers; those who had broken a bone since the age of 45; and those with poor mental health.
The most unhealthy people were those with uncontrolled diabetes and high blood pressure, and who often faced challenges with getting around and performing daily tasks.
Cancer caused 24 per cent of deaths among people over 55, but "seemed to develop randomly with respect to other organ system diseases," said the study.
The current medical wisdom suggests that people are healthy if they live without heart disease, cancer, diabetes, high blood pressure and high cholesterol levels.
But authors of the PNAS study described a different approach, known as the "comprehensive model" of health and aging, that includes factors such psychological well-being, sensory function and mobility as essential parts of a person's overall health.
Using this new lens, about half of the people considered healthy under the current medical model actually have "significant vulnerabilities that affect the chances that they die or become incapacitated within five years," said the study.
"At the same time, some people with chronic disease are revealed as having many strengths that lead to their reclassification as quite healthy, with low risks of death and incapacity." Co-author William Dale, associate professor of medicine, said the findings suggest that "from a health system perspective, a shift of attention is needed from disease-focused management, such as medications for hypertension or high cholesterol, to overall well-being across many areas."