You study nutrition labels at the grocery store and pore over menus and cookbooks for the healthiest choices. Yet if you're like most people, you don't give nearly as much thought to what you use to wash down all that wholesome food.

It's time to start. According to one recent report, Americans get an average of 22 percent of their daily calories from beverages. Sound hard to believe? "Since most beverages don't fill us up the way food does, it's easy to consume a lot of calories in liquid form and not even realize it," explains Molly Morgan, a New York-based dietitian. Unless you pay attention, those extra calories can undermine your best intentions for staying healthy.

In terms of nutrition, drinks are a mixed bag. Many harbor unhealthy ingredients such as sweeteners and artificial colors, while others are veritable health elixirs, rich in antioxidants, vitamins, minerals, and compounds that help prevent chronic illness. Most, of course, have both health benefits and drawbacks. By understanding the potential pros and cons of common beverages, you'll know which ones to reach for, which to toss, and which to modify. To that end, our experts helped us put together this cheat sheet.

Smoothies
Calories
150 to upward of 500, based on the contents

Pros
When they contain healthy ingredients, smoothies can deliver big on vitamins, minerals, antioxidant compounds, and calcium. They're a good way to add a serving or two of fruit to your day. Berries, bananas, mango, and melon all make good options.

Cons
Some store-bought smoothies are packed with calories, sugar, and artificial ingredients, says behavioral nutritionist Joy Kettler Gurgevich. Read menus and labels carefully.

Bottom Line
The best smoothie is the one you make yourself. For a basic smoothie, blend 1 to 2 cups of juice and/or milk (or milk alternative) with two cups frozen or fresh fruit (such as bananas, strawberries, and blueberries).

Herbal Tea
Calories
With nothing added, about 2 calories

Pros
Long used to treat various conditions, certain herbal teas (also known as infusions or tisanes) have medicinal value, says integrative-medicine pioneer Andrew Weil, M.D. Try sipping a cup or two of peppermint tea for indigestion, for example, or chamomile to promote relaxation. Ginger tea may ease nausea, marshmallow root may soothe sore throats and coughs, and nettle blends make for a mineral-rich health tonic.

Cons
The same properties that give herbal teas their healing potential may also cause problems for some people. (Peppermint, for instance, may trigger acid reflux in those prone to it.) And since herbal teas lack catechins, don't expect the same disease protection that true tea offers, says Weil.

Bottom Line
Experiment with herbal teas to promote health or ease minor ailments, but consult an herbalist for more extensive advice.

Tea
Calories
With no added sugar, honey, or milk, 0 calories

Pros
All from the Camellia sinensis plant, black, green, and white teas contain antioxidant compounds called catechins. This may explain studies linking tea consumption to a host of benefits, including stronger immunity and a lower risk of diabetes, cognitive impairment, heart attacks, and some cancers. The less tea is processed, the more catechins it retains. White tea has the most; black tea has the least.

Cons
All true tea still contains caffeine, which makes some people jittery. Although evidence is mixed, adding milk to tea may block the healthful effects of catechins. Pass up bottled iced teas that contain high-fructose corn syrup, artificial colors and flavorings, and other unhealthy ingredients.

Bottom Line
Tea is truly a health beverage; keep drinking it -- or start.