The reason to become wealthy

Optimism helps -- within reason.
A 2007 study by economists Manju Puri and David T. Robinson found that optimists do better financially than pessimists -- but extreme optimists don't save as much as moderate ones. After all, why pinch pennies today if tomorrow will be fabulous?

A child born into the wealthiest 20% of families has a 55% chance of staying in that quintile, according to research by Duke sociology professor Lisa A. Keister.
A child born into the poorest fifth, by contrast, has a 9% chance of reaching the top; one born in the middle, a 13% chance

Chronic health problems hurt.
Diabetes, arthritis, Crohn's disease -- these kinds of disorders are associated with less wealth.

Intelligence helps, to a point.
A study by Ohio State researcher Jay Zagorsky found that people with IQs of 130 or higher (the top 2%) earn $6,000 to $18,500 more a year than people of average intelligence. But those smarties can have trouble hanging on to their dough, Zagorsky says: "Their intelligence doesn't seem to help them delay gratification when it comes to spending."

Education pays.
Over a lifetime, the average college grad will earn about $450,000 more than a peer with only a high school education, according to a 2007 College Board study. Getting a grad degree adds another $120,000.

A 6-foot man earns, on average, $5,525 more a year than one who's 5 foot 5, according to a 2003 study. Hotties are twice as likely to make an above-average income as their homelier peers. And slim people have a higher net worth than heavy ones. Life is unfair.

Parental attention and resources are finite; the effects last through adulthood. The more brothers and sisters, the poorer you tend to be. Singletons have the best shot at affluence: They wind up with double the net worth of people with three siblings. Firstborns also have an advantage, in part because parents are likelier to pay for their college education.

Ohio State's Zagorsky found that boomers who got and stayed married accumulated 93% more wealth per person than their unhitched counterparts, partly owing to economies of scale. Divorce reduces wealth by 77%.

Married couples sans children have a median net worth of nearly $200,000; those with just one child, $134,000. Solo parents have it rough: The net worth of a typical divorced dad, for example, is no more than a third that of a married dad.

One survey shows that 50% of affluent people exercise two to three times a week, vs. 26% of poorer folks. And smoking hurts. The lifetime cost for a 24-year-old man is $183,000, calculates Frank Sloan and colleagues at Duke University and the University of South Florida.

Personality counts.
Persistence pays off, literally, in higher pay. Niceness, not so much: Being too agreeable leads to lower earnings. People who aren't very materialistic tend to be better savers, according to a study in the Journal of Economic Psychology.

Sexist men are wealthier.
Gloria Steinem may gnash her teeth, but a study by University of Florida researchers found that men with "traditional" views on gender earn about $8,500 more a year than those with a more egalitarian outlook. Egalitarian women earn about $1,500 more a year than their traditionalist sisters. Women in general are at a disadvantage: The typical woman makes 80¢ to a man's dollar and must stretch her nest egg over a longer life.

Entrepreneurialism is associated with wealth.
Families that own businesses are more affluent than others, according to research by University of Southern California economics professor Vincenzo Quadrini. The more established the business, the bigger the boost.

Risk lovers risk losing dough.
Though one study found that adrenaline junkies earn more than their cautious counterparts, there is a strong link between thrill-seeking behavior and poor investing decisions such as frequent trading and risky stock picking. Conversely, playing it too safe can hurt.

According to a 2009 study by American Express and Harrison Group, 84% of millionaires hunt for bargains. (FYI: Answer A describes Nicolas Cage, who makes millions per movie yet has lost several homes to foreclosure. Answer B describes -- you guessed it -- Warren Buffett.)