I often joke that if I were to draw a food pyramid to represent what my toddler actually eats, it would consist of a wide, sturdy base of starches and fruit and a fat midsection devoted to dairy (but let's be honest, mostly cheese). Its pinnacle would be a nearly microscopic triangle representing the two vegetables he occasionally eats (carrots and cucumbers).

Though I like to think my son is a special unicorn in all sorts of ways, I know from my shared laments with other parents that his eating habits, as specific as they are, aren't all that unique — at least for many American kids (culture has a big influence on our food preferences). In fact, there's no shortage of ink (er, html?) spilled about how to feed toddlers and young children whose eating patterns, like my son's, don't deviate much from staples like macaroni and cheese, flavored yogurt, and fruit (give or take maybe a chicken nugget or hot dog).

It made me wonder: Why do kids love the foods they love? Was society imposing these food preferences on our kids, or did they burst forth from their mothers' bodies craving fluorescent orange cheddar, buttered noodles, and bananas?

The answer is kind of the latter.

Babies are born with a preference for sweet and salty flavors

If you think about a typical toddler's favorite foods, many of them have either sweet (fruit, juice, flavored yogurt, and anything sweetened) or salty (cheese, chicken nuggets, hot dogs) flavor profiles. Meanwhile, their oft shunned foods (hi, green veggies) tend to be bitter. Scientists believe this has evolutionary roots.

Studies show that babies have a biological predisposition for sweet tastes before they're even born. And there's a purpose for this. While you may associate sweetness with sugar-sweetened junk food (not exactly a survival imperative), sugar is an easy form of energy, which young children need. "If you're developing, you have energy needs," says Rachel Herz, PhD, senses and emotion scientist and author of Why You Eat What You Eat.

In addition to signifying calories and carbohydrates, sweetness is a predominant taste signal for human milk, says Julie Mennella, PhD, researcher at Monell Chemical Senses Center. So an infant's hankering for sweetness primes them to like breast milk. But children don't outgrow this preference once they leave infancy. Throughout childhood kids gravitate toward sweetness, which could explain a toddler's preference for sweet foods, like fruit, juice, or flavored yogurt.

So what about other American kid favorites that aren't sweet, like cheese, chicken nuggets, or hot dogs? Part of the appeal could be their salty flavor profile. Children prefer a higher concentration of salt than adults. This too serves an evolutionary purpose. Saltiness is a signal for protein, Herz says. Plus, it's a mineral that our bodies need to function.

On the flip side, there's a lot of nature behind a child's reluctance to eat vegetables, which sometimes have a bitter flavor. "In nature things that are bitter tend to be poisonous, so it's advantageous to not to be consuming bitter foods. Having these predispositions are helping with survival," Herz says.

Texture and color factor into food preferences too

Of course, taste isn't the only factor that influences a child's food choices. Though less researched, a food's texture and color may also play a role. Children are naturally neophobic, meaning they're apprehensive about new foods. To a mild degree, this is adaptive, Herz says, because it steers them away from unfamiliar foods that could be poisonous.

Along these lines, a slimy, crunchy or uneven texture (think: yogurt with fruit chunks in it) can raise a child's red flags. "Texture can be a signal for food that could be contaminated," Herz says. "If you were eating something and detected grains of dirt or sand, you know you shouldn't probably eat it. Likewise, if you're eating something with little bits, your reaction is to be cautious. That's connected to biology." This could make the unnaturally smooth texture of processed meats, like chicken nuggets or hotdogs, more appealing than the less predictable consistency of a real chicken breast or piece of pork.

Color too may be a signifier. Children may show a preference for foods that are white, such as rice, plain pasta, or bread because they perceive them to be "safe." As far as why kids love the vibrant orange and yellow of processed cheeses, "foods that are yellow have been shown to make people happier," Herz says.

How to expand a picky palate

Despite the fact that there's a biological basis for flavor preferences, they aren't set in stone. One of the best ways to raise an adventurous eater is to start 'em young. "When introducing solids, expose a baby often to bitter vegetables, fish, and spicy foods — foods that most toddlers would refuse," says Dr. Natalie Muth, MD, RD, a pediatrician and registered dietitian based in California.

But what about those of us for whom babyhood is a mere memory? Is all hope lost?

Not quite. Food preferences will evolve over time, independent of how we parent. Though our partiality to sweet and salty foods lingers through childhood, it lessens with age. For instance, if you ask a four-to-six-year-old to sweeten a drink to their preferred level of sweetness, they'll put in 12 sugar cubes, while an adult would add only seven, Herz says.

Parents can also help shape and broaden their children's picky palates in a number of ways, as well:

Prioritize exposure over clean plates. For a parent desperate for a child to try new foods, the sight of a barely-touched plate can be stressful. But Muth urges moms and dads to try not to fret.

"Be as relaxed as possible about offering a food they'll probably reject," she says. "Don't be so invested in whether they eat or not. Focus more on exposure," she says.

It can take 15 to 20 exposures for a kid to come around on a food. The key is that they're trying it. "They don't have to chew and swallow," Muth says, it just has to touch their tongue."

Make food more appealing. Rather than forcing toddlers to try new things, "the key is to find tricks to make them want to try the food out of their own volition," Muth says. A few ways to drum up interest in new foods include getting kids involved with meal prep or letting them pick out foods at the store. Or you could gussy up a disliked food by cutting it into a fun shape or putting it in a bag covered in stickers.

Try 'bridging.' Strategically bridge the gap between your child's likes and dislikes. Start with a food your child likes and use it to introduce a food that either has a similar flavor but different texture or a different flavor and similar texture.

For example, if your child likes french fries, offer sweet potato or zucchini fries because they have the same texture, Muth suggests. Or, if your child likes sweet potato fries, you could introduce them to mashed sweet potatoes, which feature the same flavors, but a different texture.

If that goes well, move to similarly prepared but gradually less sweet foods, such as mashed squash or mashed carrots.

Pair likes with dislikes. Bring your kids around to bitter-tasting foods by serving them with sweet or salty flavors (depending on what they like). Add cheese sauce to broccoli to make it more alluring. "Once they like that, progressively take off more cheese, until they've transitioned to eating it plain," Muth says.

Model an enjoyment of eating. One thing that becomes more important with age that may influence flavor preferences from a psychological perspective is the social context of eating, Herz says. A meal becomes more than meat and veggies on a plate when it becomes associated with having fun or being surrounded by loved ones. Parents can nurture this by showing their kids just how enjoyable eating can be when everyone sits down for family dinners.

This story originally appeared on Apparently.