Added sugar is everywhere in the food supply. It's so ubiquitous that you might find some packaged and processed foods unappetizing without it.

Evolution has hard-wired our palates to prefer sweet-tasting foods to obtain quick energy and to avoid bitter-tasting poisons. But in America today, our diet has reinforced and strengthened that preference beginning in early childhood. Americans take in an average of more than 17 teaspoons of sugar (about 290 calories) a day from added sugars, often in sweetened beverages, far more than recommended.

Sugar is added to countless food products, including breads, condiments, dairy-based foods, nut butters, salad dressings, and sauces. The sugar is added not just to impart sweetness. It's also used to extend shelf life and adjust attributes like the texture, body, color, and browning capability of food.

To start reducing added sugar in your diet, first it helps to know where it comes from. Here are the basics.

Where's the sugar?

Unless you consume only whole, unprocessed foods, you are bound to have added sugars in your daily diet. Sugar-sweetened beverages lead the pack, but many other foods also contain added sugar—sometimes a substantial amount in a typical portion.

Sugar-sweetened beverages.

Sugar-sweetened beverages contribute about half of the total added sugar in the U.S. food supply. The source of the sweetness in most products is high-fructose corn syrup. These sugary drinks include any of the following:

• regular soda
• juice drinks, like fruit punch and juice "cocktails" (but not whole fruit and vegetable juices)
• energy drinks
• sports drinks
• sweet tea
• sweetened coffee drinks
• sweetened water
• any other beverages with sucrose or high-fructose corn syrup added to enhance sweetness.

It's important not to confuse sugar-sweetened juice drinks with whole fruit juices. Processed beverages like fruit punch or cranberry juice cocktail contain a fair amount of added sugar—in the case of cranberry juice cocktail, the sugar is added to counter the naturally sour taste of cranberries. This is an example of a fruit drink that is also a sugar-sweetened beverage, and therefore a source of added sugar. Whole (100% fruit) juices contain only the sugars in the juice extracted from the fruit or vegetable. However, it's a good idea to limit even whole juices in your diet.

Sugar-sweetened drinks can pump a large amount of added sugar into your body, and quickly. These beverages are not as filling as sweet whole foods like fruit, so it's easier to consume a lot of them. On average, Americans get more than 200 calories a day from sugary drinks, about four times what we consumed in 1965.

Sweets and desserts.

Brownies, cakes, cookies, doughnuts, ice cream, pastries, pies, puddings, and sweet rolls are just some of the processed foods widely understood to contain substantial amounts of added sugar.

Honey and syrups.

Sugars naturally present in honey and syrups, including maple syrup, are also considered added sugars. Although honey and syrup are sold as freestanding products, you don't eat them by themselves. They are squirted into hot drinks, drizzled on pancakes and waffles, or added during baking or making sweets.

Condiments.

Condiments are defined as spices, sauces, or other preparations that you add to food to enhance its flavor. Tomato ketchup, relish, barbecue sauce, salad dressings, and salsa are condiments, and they can contain considerable amounts of sugar per serving.

Prepared foods.

A vast variety of prepared foods contain additional sweeteners. Breakfast cereals contain added sugar, but so do ready-to-eat meals, breads, soups, tomato sauces, snacks, and cured meats.

Among the many processed and prepared foods with added sugar are sugar-sweetened yogurts. Plain unsweetened yogurt contains naturally occurring milk sugars, but added sugar can double or triple the total amount of sugar.

New nutrition labels in the works will make it easier to know how much of the total is added sugar as opposed to natural milk sugars.

To learn more about ways to improve diet while keeping your sugar intake to a minimum, check out Reducing Sugar in Your Diet, a Special Health Report from Harvard Medical School. 

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Are natural sugar alternatives healthier?

Many people are seeking out what they perceive to be healthier alternatives to refined (granulated) white sugar or high-fructose corn syrup. They may have heard that plant-based natural or organic sweeteners such as agave syrup (sometimes called nectar) or coconut sugar are less likely to trigger spikes in blood sugar. Less-processed "raw" sugars, maple syrup, or honey also may be perceived as better options simply because they are more "natural" than highly refined table sugar.

Popular sugar alternatives do come from things in nature, such as tree sap or beehives. But the sugar in them is the same as what you'll find in a bag of "unnatural," refined white or confectioner's sugar. The same goes for sugars labeled "organic" or "raw." Though less-processed sugars may contain trace elements and minerals that refined white sugar lacks, they still end up as glucose (blood sugar) after the body breaks them down.

In the case of agave syrup, there is a difference in the way the body processes it compared with table sugar. Agave syrup is mostly fructose, which does not directly raise blood sugar (glucose) levels. Instead, the fructose goes to the liver to be converted to glucose.

On the other hand, consuming excess amounts of fructose can cause the liver to start making fat in the form of triglycerides. Chronically high triglycerides raise the risk for diabetes and heart disease.

In the end, the key message is "the dose makes the poison." Whatever type of sugar you use to sweeten your tea or oatmeal, or to cook with, the important thing is to limit the total amount of added sugar in your diet.

To learn more about ways to improve diet while keeping your sugar intake to a minimum, check out Reducing Sugar in Your Diet, a Special Health Report from Harvard Medical School. 

Images: HandmadePictures/Getty Images