Older adults are often portrayed as crotchety, cranky and mistrustful. These pervasive stereotypes are not only untrue, they may also be harmful, says a new paper published in the journal Social Psychological & Personality Science.

Researchers from Northwestern University and the University at Buffalo conducted two studies that highlight the important role that trust plays in overall wellbeing as we get older.

The first study involved an analysis of data on more than 197,000 men and women from around the world. The data set spanned across three decades and indicated that, regardless of the time period in which an individual was born, their willingness to trust other human beings got stronger as they got older.

These findings were replicated, on a smaller scale, during a separate study of 1,230 American adults.

"When we think of old age, we often think of decline and loss," says Claudia Haase, assistant professor of Human Development and Social Policy at Northwestern in a press release. But, she adds, "People really seem to be ‘growing to trust' as they travel through their adult years."

More trust, better health

This increased capacity for trust could hold the key to combating the epidemic of loneliness that plagues so many older adults.

Obesity is regarded as one of the most serious threats to American health, yet recent research indicates that loneliness is twice as deadly as being extremely overweight. Feeling isolated from others increases death risk by 14 percent and is often accompanied by increased inflammation, elevate blood pressure, interrupted sleep and depression. Read more about the Deadly Consequences of Loneliness.

On the flip side, maintaining strong interpersonal ties has been associated with better physical and mental health.

The drawbacks of too much trust

There is, however, one big drawback to becoming more trusting with age: an increased risk for falling prey to a scammer.

A 2012 UCLA study found that people over 55 weren't as adept at picking up on cues of untrustworthiness in a person's face, when compared to adults in their 20s. Brain scans showed that the parts of the brain associated with assessing danger and risk also appear to be less active in older adults. Study authors partially attribute their findings to the increased "positivity bias"--a tendency to be more satisfied, and focus on the positive aspects of life-- that is often observed in aging individuals.

"The consequences of misplaced trust are severe," study authors write. "Older adults are disproportionately vulnerable to fraud, and federal agencies have speculated that excessive trust explain their greater vulnerability."

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For instance, an aging loved one who isn't aware of the many ways that scammers can steal information online may share too much information on their social media profiles, unintentionally making themselves vulnerable to cyber crimes like the Sweethart Scam or the Grandparent Scam.

AgingCare.com Expert, Carrie Kerskie offers additional insights on how to protect your aging loved one (and yourself) from fraud.