Advertisers are missing the mark when it comes to reaching older Americans, a recent study shows.

Marketing images distort how people 50 and older live by portraying them as frail and dependent, as opposed to active and engaged.

Nearly half the U.S. population is over age 50, but you'd never know that from perusing most online ads. In fact, despite their immense purchasing power as consumers, older Americans are largely ignored by marketers. On the rare occasion they are represented, meanwhile, they are typically miscast or even caricatured as dull, behind the times or just plain doddering.

"Many marketers are still stuck in the picture of a retired couple in beige looking a little vacant at leisure or worse, being very frail and befuddled," said Barbara Shipley, senior vice president of brand integration at AARP. "There is not 'one face' of aging: There are millions of stories — and that's what we love, that people can age the way we want to and they don't want a bunch of pictures to be telling them how they should be aging."

AARP last year analyzed a random sample of more than 1,000 images drawn from news sites, blogs and social media platforms including Facebook, Instagram and Twitter. Although 46% of the U.S. adult population is over 50, only 15% of the images containing adults included members of that age group, the organization found.

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The bigger picture: Older Americans are far more diverse, vibrant and wide-ranging in their interests than they're typically portrayed to be in online marketing, which tends to dwell on their wrinkles and gray hair. That amounts to a huge missed opportunity for companies looking to connect with a large demographic that's inclined to spend.

Outdated stereotypes

Apart from misrepresenting physical traits, the online images reviewed by AARP often promote outdated stereotypes of how 50-plus people spend their time. One in three images showed them at home rather than on the job, versus 1 in 10 of their younger peers, despite older Americans making up 30% of the U.S. workforce.

"At best, they are portrayed in a removed location where someone younger can visit (e.g., at home)," the AARP study's authors wrote.

Also missing from images featuring fiftysomething "quinquagenarians"? Technology. That perpetuates another stereotype of older adults as hopelessly behind the digital times. The reality? People 50 and older are expected to spend more than $84 billion on tech products by 2030, according to AARP.

Advertisers are only hurting themselves in peddling such cliches, Shipley said. "People want to align with brands that understand them and get them and also lead with purpose."

"The power of the longevity economy is one of the most important things for marketers to understand. It's not just charitable — there is a real bottom line benefit to getting it right," she added.

Updated images

Cynthia Cruver, a partner at 3rdThirdMarketing, an agency that specializes in reaching the 50-plus community, highlighted some of the negative effects of such ageism.

"When the nuances are missed, and the images are misrepresenting people, it's a knock on their self-esteem," she said. "If you keep seeing imagery of yourself as an age group being not attractive, not strong, not active, it starts to weigh on your psyche, and it changes your self-esteem."

AARP, for its part, wants to give marketers tools that combat this. The group this week teamed with photo agency Getty to launch a database, dubbed "Disrupt Aging," featuring images of older adults playing sports, engaging with friends and using consumer technology.