Try new things. Not too much. Mostly experiences. Many parents of young children struggle to introduce new foods into their kids' diets. About half of American children are picky eaters by the age of two; they are, in the vernacular of nutritionists, "food neophobic." Our pediatrician once told me that one of our sons, who was a fussy eater, would need to try a new food at least six times before the taste would no longer fill him with fear and loathing. My wife and I wanted to fight our son's food neophobia for some practical, nutritional reasons, but more fundamentally, we wanted him to eat adventurously so he could enjoy this part of life. Openness to a wide variety of tastes and smells enhances the pleasure of eating.

This is an instance of a larger truth: Openness to a wide variety of life experiences, from visiting interesting places to considering unusual political views, brings happiness. "Only someone who is ready for everything, who doesn't exclude any experience, even the most incomprehensible," Rainer Maria Rilke wrote in his Letters to a Young Poet, "will himself sound the depths of his own being."

He had the data on his side. Openness, also known as neophilia, is strongly, positively associated with happiness. Of course, you can push this too far, becoming chronically disgruntled without a constant stream of novelty, or turning into a danger addict always searching for the next extreme experience. True happiness comes from a healthy, balanced neophilia that cultivates a love for the adventure of life.

Neophilia is correlated with happiness insofar as it is associated with extroversion, and extroversion strongly predicts happiness. But neophilia also causes happiness because it is an engine of interest, which, according to the research psychologist Carroll Izard, is one of the two basic positive emotions (the other being joy). It is highly pleasurable to have your interest piqued, which naturally happens when you're exposed to new things; neophiliacs thus stimulate this positive emotion more frequently and intensely than neophobes.

A big part of the neophilic tendency is inherited. A number of studies have measured this; for example, a 2002 meta-analysis of research on twins found that openness to new experiences is about 57 percent genetic. A few years later, researchers in Japan found that a particular mitochondrial enzyme called monoamine oxidase A—which neutralizes dopamine, serotonin, and norepinephrine—is more active in the brains of individuals most likely to have novelty seeking as a core personality trait.

This still leaves nearly half of neophilia to be explained by other factors. There are plenty of candidates: Openness tends to increase into early adulthood, but from one's 20s to one's 80s, it declines by about 17 percent for the average person. Politically conservative people are less neophilic—at least socially and economically—than progressives are. Some researchers believe that higher intelligence and general knowledge drive up openness. Upbringing also matters: Scholars have found that nurturing parenting styles lead to openness in children, while authoritarian styles lead to the opposite.

Even living in a modern, consumer-driven society might play a role. Colin Campbell, a professor of sociology at the University of York in the United Kingdom, has written that "in traditional societies novelty tends to be feared" and that an insatiable desire for the novel is a trait of the modern consumer.

This view brings us to neophilia's dark side. In her book New, the writer Winifred Gallagher argues that the accelerating novelty of gadgets leads people in modern societies to overspend on things we don't need and that don't enhance our well-being in any way. This hypothesis is hard to argue with, I realize, as I glance down at my smartwatch, which nags me about my caloric intake, graphs my (poor) sleep patterns, tells me how far I am from reaching the right number of steps each day, and interrupts me with about a thousand other "conveniences" that distract me from enjoying my life.

There are more serious negatives to neophilia than mindless consumerism. High levels of neophilia are associated with risk-taking behavior in childhood, and thus to addiction later on. And while it encourages us to explore and create as we look for new stimuli, it also makes contentment especially elusive as we build up a tolerance for novelty with amazing speed. Undisciplined neophiliacs are often restless wanderers, jumping between projects, quitting jobs, and moving frequently—which, as Benjamin Storey and Jenna Silber Storey show in their book Why We Are Restless, are all things that tend to make people less content in life.

Finding a healthy degree of neophilia is a bit of a high-wire act (which, come to think of it, neophiliacs might enjoy trying). Based on the research, here are four principles for cultivating a balanced neophilia that will help make you happier.

First, regularly interrogate your tastes, and run experiments. One common misconception is that our preferences are set in stone and there's no use trying to change them—especially as we age and become grumpier about new things. The data don't support this assumption. Indeed, some studies show that older workers are more open than their younger colleagues to changes in their job responsibilities. Meanwhile, our senses of taste and smell tend to dull as we age, making us more or less attracted to certain foods.

Take an inventory of the things you dislike and currently avoid. Then review your list, and try the things on it. Food is a good place to start. You can also try visiting places and engaging in activities that you'd normally spurn. Do you hate opera? Maybe; maybe not. The older you might hear it differently than the younger you did.

Second, make a point of choosing curiosity over comfort. Write up a list of new experiences and ideas you've yet to try, and explore one per week. They don't have to be big things. Perhaps you never read fiction, not because you don't like to but because you are more accustomed to biographies; pick up a novel. If you usually watch an old favorite movie instead of something new, or choose the same vacation spot every year, be sure to branch out.

Third, avoid the trap of newness for its own sake. If you're pretty neophilic, you might already be taking the suggestions above, and reaping the rewards. But you might also be prone to restlessness and instability, and look to material novelty for a quick fix. In this case, try resetting your satisfaction with a "consumption fast": Don't buy anything inessential for two months. Your focus will likely migrate from online shopping to more satisfying pursuits.

Similarly, if your neophilia leads to impulsiveness, consciously add in a bit of time to your decision making. Research has shown that in a crisis, slower decision making leads to better outcomes. For neophiliacs, everything is urgent; they would do well to make decisions more deliberately. Want to take that job as a bungee-jumping instructor? Sleep on it. Then spend a couple of days imagining what your life will be like in three years if you make that choice, and ask a couple of trusted friends for advice.

One of the delights of life is seeing ourselves and others change—especially our children as they grow up. Take my food-neophobe son: He is now a 21-year-old, six-foot-five Marine infantryman, and transforms into a human piranha when you put any food in front of him. When I recently reminded him about his early-life pickiness, he responded, "I guess I just wasn't hungry enough."

And therein lies a great secret to happiness—the most important lesson about neophilia. The well-being associated with neophilia isn't actually about new things at all; it is about a hunger—for life. To cultivate a healthy appetite for life's offerings is to open your eyes to a world of abundance, beauty, sanctification, and adventure. And that just can't help but bring joy.