Even inside holiday desserts, can apples help keep the doctor away?

Thousands of years after apples spread from their ancestral homeland in central Asia into Europe, a legendary golden apple is said to have sparked the Trojan War. Then the Romans mastered the art of grafting apple trees to feed soldiers in the far-flung empire.

Since then, apples have been enshrined in Celtic rituals, Christmas trees and imagery, Persian poetry and Turkish folklore. Eventually, a person could be "rotten to the core" or "the apple of someone's eye." And, of course, an apple a day really can help keep the doctor away.

Few fruits are as universally enjoyed as apples, becoming integral to holiday traditions that transcend cultures around the world. In Germany, they come in custardy cakes with cinnamon and raisins. In Britain, they're baked into buttery crust for minced pies with dried fruit and brandy. In Japan, they are cooked into yokan, a jelly-like mixture with red bean paste and sugar.

For Rosh Hashanah, the Jewish New Year, people eat apples and honey as they greet each other by wishing a sweet year, and at Hanukkah, they are mixed with cream cheese and baked into a moist cake.

Today, people in the U.S. eat roughly 9 pounds of fresh apples each year, making them as American as – well, you know.

"Like European humans, the apple came from Europe and then quickly naturalized into North America," said John Bunker, an apple historian. "At this point, there are hundreds of millions of apple trees growing in the northern U.S. that did not require any human to plant them. They're just planting themselves all over the place."

Bunker said he grows about 400 varieties of apples, called cultivars, on his farm in Palermo, Maine.

It's a research orchard with a blend of rare, historic and experimental varieties such as Redfield, with its red flesh best suited for cooking, and Black Oxford, a purple, speckled variety that ripens in winter but gets tastier after a few months in storage. And there are Frostbites – "the grandparent of honey crisp," Bunker said – with the crunchiness of that blockbuster fruit but a flavor that evokes olives to some people and sugarcane to others.

His farm represents a mere drop in the cider bucket of varieties. A 2016 illustrated compendium of apples documented nearly 17,000 cultivars that had grown in the United States and Canada alone, 80% of which have disappeared.

The U.S. ranks third in apple production, behind China and the European Union, and domestic growth is expected to dip this year. The Gala variety leads the way in the U.S., followed by Red Delicious, Granny Smith, Honeycrisp and Fuji.

But to health experts, almost any type of apple is good for you, especially for your cardiovascular health.

"There are so many benefits to apples, and there's been a lot of different studies that have shown that benefit," said Julia Zumpano, a registered dietitian who specializes in disease prevention and management at the Cleveland Clinic.

Apples contain 3 to 5 grams of dietary fiber, most importantly a type of soluble fiber called pectin that promotes gut health. Soluble fibers can bind around bile to help rid the body of extra cholesterol, which can build up in the arteries as plaque and contribute to heart disease and stroke risk.

Apples also are high in antioxidants, including vitamin C, and beneficial phytochemicals, such as quercetin. Antioxidants in general protect cells from damage, keeping the lining of blood vessels more stiff and supple, Zumpano said. But quercetin in particular supports a healthy gut microbiome by stopping certain microbes from growing, which combats inflammation that can lead to heart disease.

Zumpano said the high potassium content in apples can help with high blood pressure. Potassium contributes to muscle contraction and producing a heartbeat. It also helps balance fluid in our bodies.

Just don't skip the apple peel, which contains much of the nutritional value, she said. Some people may worry about traces of pesticides, but Zumpano said the skin is safe to eat as long as the fruit is well washed.

"Use a washcloth or your hands to scrub the outside," she said.

Around the holidays, apples show up in sugary, butter-laden desserts. But Zumpano said you don't have to skip that slice of apple pie as long as you maintain an otherwise balanced diet with plenty of fresh fruits and vegetables and have dessert in moderation.

To make holiday treats healthier, start with half the amount of sugar in any recipe. "Apples are already sweet," she said.

Since the unhealthiest part of apple pie, for example, is the crust, Zumpano suggested using an apple crumble that includes a topping of baked oats, chopped nuts and a bit of maple syrup.

Whole roasted apples also are a delicious dessert on their own, Zumpano said. Place whole, skin-on apples in a glass pan and sprinkle cinnamon on top. Coat the pan with avocado oil or 100% apple juice for extra moisture, then bake uncovered at 350 degrees for 20 to 25 minutes.

"They're very, very sweet when you bake them," she said. "They almost caramelize, and the core almost just falls off."

Apples shine in many savory dishes as well, such as paired with pork or lamb. And chopped they can add a sweet crunch to chicken or tuna salad.

Zumpano said people concerned about their weight shouldn't worry about the natural sugar and carbohydrates in fresh fruits.

"It will really be more helpful than harmful," she said, "especially when paired with more of a whole foods-based diet."

Eat It or Leave It? is an American Heart Association News series that takes a closer look at the health benefits and drawbacks of specific foods and drinks.