What's your love destiny? That all depends on the size of your pout, according to a study from the University of Leicester in England.

Couples whose lips are of a similar size and shape are more likely to stay together. The researchers found that 88 percent of happy couples had lips that mirrored each other's.

The study also showed that while men are instantly attracted to women with a luscious pout, they don't consider them marriage material. In fact, women with thinner lips are 57 percent more likely to have longer relationships than their pouty-lipped counterparts. Ditto for men: Thin-lipped guys are 39 percent more likely to have a longer-lasting relationship compared to men with full lips.

The size of your kissers can also reveal loads about your personality, say the researchers:

If you have...

A large mouth:

You're laid back, relaxed, easy, generous, and enjoys being in the middle of life.

A small mouth:

You're independent, strong-willed, precise, have great endurance and fighting spirit.

Full lips:

You're emotional, passionate, sensual, expresive, talkative and outgoing.

Thin lips:

You're efficient, achieving, disciplined, make clear and precise statements, and get on with life without fuss.

The next time you and your guy head down to the ice-cream parlor, eyeball his order to get the inside scoop on his personality. In his book What Flavor is Your Personality? Dr. Alan Hirsch, neurological director of the Smell and Taste Research and Treatment Foundation in Chicago, uses the results of a personality survey to match people's traits with their favorite foods, including ice cream. "It was amazing to discover how distinct personalities corresponded with ice cream flavors," says Hirsch.

Based on the science of "flavorology", here's what your guy's favorite flavor says about his personality:

Vanilla
Contrary to what you may expect, vanilla lovers aren't bland or boring. Rather, your guy is quite the risk-taker who sets high goals for himself and tends to live a hectic life with an overly filled schedule. He's fun-loving, expressive and prefers a close, secure relationship.

Most compatible with: Other vanilla lovers

Double chocolate chunk
Your partner is creative, charming and enjoys being the life of the party. When it comes to your love life, he often expects a lot of attention from you, but he also puts in just as much effort into the relationship.

Most compatible with: Butter-pecan or chocolate chip lovers

Strawberry
Your man is loyal, trustworthy, and tends to be a little reserved. He's not one to fall head-over-heels in love with someone in a flash, but when he does go into a relationship, he stays committed.

Most compatible with: Chocolate chip lovers

Chocolate chip
He is a confident and ambitious guy who is charming in social situations. Because of his go-getter nature, he can be intolerant of defeat.

Most compatible with: Butter-pecan or double chocolate chunk lover

Butter pecan
He is a perfectionist who is conscientious and detail-oriented, which makes him a very attentive lover or spouse. He also tends to be sexually reserved.

Most compatible with: Other butter-pecan lovers

What your date orders at Starbucks says tons about his personality, according to Dr. Alan Hirsch, Director of the Smell & Taste Treatment and Research Foundation and author of What's Your Food Sign?

It may sound a tad far-fetched, but Dr. Hirsch has some science to back up the statement: His survey of 18,631 men and women revealed a strong correlation between the participants' drink preferences and their personalities.

Here's what his coffee order says about him:

Black coffee: He's aggressive, ambitious and independent

Café au lait: He's traditional and laid-back

Chai tea latte: He's shy and stubborn

Hot chocolate/ Mocha-flavored coffee: He's a dreamy romantic

Iced mocha: He's spontaneous and seductive

Iced tea with lemon: He's sexually shy and inhibited

If you want to know more about the guy you're dating, his family tree is a good place to start -- or more specifically, his birth order or the order he was born into a family. "While other factors, such as age, race, and gender, all play a role in shaping personality, research indicates that the number one factor influencing personality is birth order," explains William Cane, author of The Birth Order Book of Love, who has analyzed the birth order of 6,000 celebrities, historical figures and couples.

Birth order personality
Firstborn
Because firstborns are usually given more responsibility from young to look after their siblings, they typically grow up to be dominant, super-responsible, organized and competitive.

Middle child
The middle child is a people-pleaser. He or she is diplomatic, and it's difficult to get them to take a stand. The middleborn also tends to be a little manipulative.

Lastborn
Lastborns are friendly, creative individuals who love challenging the status quo. They're more adventurous than their siblings and are the risk-taker in the family, although they also tend to be needy at times.

Only child
An only child is used to being in the spotlight within the family, so he or she tends to crave attention. Being an only child also means that he or she is unlikely to know very much about the opposite sex.

Twins
Twins have a strong bond and therefore always think of the other before making a decision. Their thoughtful nature makes them considerate romantic partners.