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Compliments are the new crack. Young Americans place such a high value on their sense of self-worth that they crave praise and compliments more than food, friendship, or even sex, finds a new study. But--like alcohol or nicotine addicts--even when they get what they want, many self-esteem junkies still don't feel satisfied.

One major sign of addiction is that people want or need something more than they actually enjoy it, explains Brad Bushman, Ph.D., a communications professor at Ohio State University. Last year, Bushman's research showed that today's college students prefer self-esteem boosts to alcohol, friendship, sex, or money. In his new study, Bushman repeated last year's experiment on 900 adults ranging in age from 18 to 90. The study group also completed a survey that measured symptoms of depression.

Here's what Bushman and his colleagues discovered: The younger the adult, the more he or she valued self-esteem boosts. Also, regardless of age, people who strongly desired self-esteem--but did not tend to enjoy it when they had it--were the most likely to show signs of depression, the study says. In other words, depressed people show signs of addiction to self-esteem, Bushman explains. (Feeling blue? Try these 5 Easy Fixes to Lift Your Mood.)

So, what's going on here? Bushman points to the 1969 publication of The Psychology of Self-Esteem, by Nathaniel Branden, as the launching point for a new generation of Americans who would become "obsessed" with self-esteem. And as each new generation enters a culture that puts a premium on self-worth, younger Americans spend more time craving and searching for self-esteem boosts--and less time thinking about others. All that time spent thinking about yourself not only contributes to depression, but it makes society a less kind and gentle place, Bushman says.

Along with Bushman's research, a University of Ottawa study showed that egocentrism--or thinking only of yourself--is a major contributor to depression. So what's the cure? Well, thinking about others. Donating your time to charity lowers depression and anxiety levels, finds a University of Texas study. And you only have to volunteer once a month to give your life a greater sense of purpose, according to research from Duke University and the National University of Singapore. (Looking for rewarding ways to give back and spend your down time? Check out America's Manliest Charities.)

Don't have time for that? Check out these three little-known organizations. You can donate online in minutes, and spend your commute thinking about the good you've done for others.

1. VillageReach

Most charities have a simple, easily defined goal that makes them attractive to prospective donors. VillageReach, on the other hand, is concerned with health care logistics. Huh? You may not know it, but one of the biggest roadblocks to improving health care worldwide is making sure the right supplies and personnel make it to the places they're needed most. These guys are doing their best to ensure that happens. (villagereach.org)

2. Charity:Water

If you live in America, you take H2O for granted. But 800 million worldwide, or 1 in 9 people, still don't have access to clean water. Charity: Water, which started just 5 years ago, is committed to changing that through simple, time-tested solutions like building new freshwater wells and rain catchments. (charitywater.org)

3. Horizons National

Some people are born into families that can provide access to a good education--but many American children aren't so lucky. Every summer, Horizons National offers hundreds of underprivileged children 6 weeks of supplemental academic instruction, cultural enrichment, and confidence-building activities at well-regarded local schools. (horizonsnational.org)

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