Prepared properly, smoothies are a tasty way to pack extra nutrients into your diet.

How do you build a better smoothie? A question that plagues post-modern society, to be sure. All kidding aside, however, smoothies have become big business, with a bevy of products and specialty shops available to satisfy your every desire for drinkable fruit. And while blending up a few berries sounds like a simple enough way to eat a more healthful diet, as with so many things in our world today, we've managed to turn something that was once simple into an increasingly complex science.

So whether you're an athlete looking for a drink to help with muscle recovery, a busy professional who needs to get out the door in a hurry or a parent looking for a nutritious snack for kids on a hot day, here is a primer for building a better smoothie for both health and taste.

THE FRUIT

When it comes to picking the ingredients for a smoothie, you really can't go wrong by starting with any kind of fruit, whether fresh or frozen. Bananas are probably the most common choice, partially for the taste, but also because they add a rich texture, especially if they've been frozen before blending. As for the calorie content, don't be afraid:While they are one of the more energy-dense fruits, the roughly 110 calories a banana provides is quite low compared with many other snack foods -- and few foods of any kind are as rich in blood pressure-lowering potassium.

Aside from bananas, berries of any kind are a great choice for their antioxidant and fibre content, as well as their relatively low calorie content. So if you're a fan, then now is the time of year to load up on strawberries, raspberries and wild blueberries, or any other locally grown fruit, which will not only up the quality of your diet, but also eliminate the carbon footprint that comes with choosing more exotic fruits from overseas.

If you want to step beyond bananas and berries, however, then consider fresh or frozen peaches, melons, pineapple, oranges or mangos. Not only will they add a twist of flavour, also a blend of potentially disease-fighting nutrients, known as flavonoids, that is unique to each fruit.

THE "SUPER FRUIT"

If you're a fan of the growing number of smoothie bars popping up across North America, then you're probably familiar with the various "super fruits" that are added to pump up your drink of choice. One of the most popular is the acai (pronounced a-sigh-EE) berry, a product of the Brazilian rainforest that peaked in popularity after being featured on The Oprah Winfrey Show in 2008. Despite a limited body of research, acai supporters argue that it is a powerful, antioxidant-rich superfood that can be useful for everything from weight loss to colon cleansing. While a number of dubious companies have sprung up selling purported acai-based weight loss products, the berry itself -- like all berries -- is nutritious, even though it probably won't live up to the hype it has generated.

THE PROTEIN

If you combine fruit and ice cream or sorbet and call it a smoothie, you're probably better off calling it dessert. Not only will you be including a chunk of added sugar in your diet (which is to be expected if it is dessert, but not so much if you're using it as a meal or snack), it also lacks a source of protein, which means you are more likely to feel hungry shortly after eating it. Likewise, many of the so-called smoothie products available at grocery stores today are simply fruit purees, which means you're not only missing the protein, but they're often blended with mixture of fruit juices that simply don't have the same nutritional value as the whole fruit.

If you want to build a smoothie that will satisfy you and can serve as a meal or substantial snack, then use whole fruit whenever possible, and include a source of protein. Yogourt, milk and soy beverages are all good places to start (all three contain about eight grams of protein per cup), but you can ramp up the protein even more with a scoop of whey protein powder (one scoop of which usually provides around 20 to 25 grams of protein).

THE CALORIES

While smoothies can undoubtedly be a highly nutritious meal or snack, they can also pack a serious caloric punch if you're not careful. At the popular juice bar Booster Juice, for example, most smoothies contain between 375 and 425 calories -- enough to serve as a small meal for most people. While not an issue if you use it to replace a 600 calorie burger, it can be a problem if you pick a smoothie over ice cream or frozen yogourt, thinking you are saving yourself a few calories (most single-scoop ice cream cones contain between 250 and 300 calories, cone included).

Likewise, if you are making your own smoothie at home, then be careful not to add too many extra calories, particularly from fats and oils. While they are certainly good for you, high-fat ingredients like peanut or almond butter, flaxseed or hemp oil can pack a major caloric punch (about 90 calories per tablespoon of nut butters, or 120 calories per tablespoon of oils) that can turn your seemingly harmless drink into a caloric bonanza before you know it. The bottom line: Use careful portion control, or save the nuts for a snack instead.