Does This Calorie Make Me Look Fat?

You've most likely heard the term "a calorie is a calorie" before. This popular phrase, after all, encompasses the nitty gritty behind the foods we eat and weight we maintain. But the truth is, it's really not that simple -- and not all calories are created equal.

Let's start with what a calorie actually is. As defined by Encyclopedia Britannica, a calorie is " the amount of heat required at a pressure of 1 standard atmosphere to raise the temperature of 1 gram of water 1° Celsius." From a food standpoint, and often used in the dietetic world, a calorie measures the calorific, heating or metabolizing value of foods. Simply put, calories give us energy, and that energy is transferred in a manner that allows us to perform everyday tasks on a day-to-day basis. These are the calories we "burn" for energy. Any calorie left over after we've used what we need for energy gets stored as fat. Any calorie. That's where the term "a calorie is a calorie" really comes from -- but that's also where the justification ends. Further, going on a "diet" is often entwined with the theory that all calories are created equal, and that's probably why diets fail. Here are the four types of calories that should dominate your diet 90 percent of the time.

1. Calories from fiber. Dietary fiber, the non-digestible part of plants, is well-known for lending a hand in keeping you regular, but that's not it's only act of kindness. Research shows greater dietary fiber intake is associated with a lower risk of both cardiovascular disease and coronary heart disease. There are two types of fiber: soluble and insoluble. Soluble fiber, which dissolves in water, helps slow the digestion of food and can be found in oats, some vegetables, fruits and legumes such as dried beans and peas. Insoluble fiber helps promote regularity and a healthy digestive system and can be found in the skins of fruits and vegetables, as well as the bran portion of whole grains. Both types of fiber help your body thrive. We all know fruits and veggies are good for us, but what many don't understand is why 100 percent whole grains trump refined grains -- fiber (ding, ding, ding!). Let's talk bread. Fiber, along with protein, carbs, B vitamins and phytochemicals, is abundant in 100 percent whole-grain bread, making it a terrific option to include in your diet. White bread, on the other hand, has been stripped of all the good stuff, including fiber, leaving nothing but the carbs, which your body quickly converts to sugar in your bloodstream -- a reaction you want to avoid. Bottom line: Eat your fiber!

2. Calories from colorful foods, naturally found in nature. If you took a picture of your diet, would it be a colorful picture filled with natural deep greens, vibrant purples and reds, and earthy browns? Or would it be crammed with dull whites and artificial pigments? Quality calories always come from items rich in color naturally produced by nature. Although jelly beans, red licorice and superman ice cream are colorful, their colors are unnaturally produced -- and therefore, do very little good for your body. Fruits and vegetables, whole grains and legumes should color your diet daily. Dark, red, blue and purple foods such as red cabbage, berries, black beans and black rice are rich in anthocyanins, a type of antioxidant flavonoid with cancer-fighting compounds. Bright yellow, orange, red and green foods such as carrots, leafy greens and tomatoes have carotenoids, antioxidants with disease-fighting compounds. In the plant world, colorful calories are endless, and all options are excellent. There are, however, some notable winners, such as strawberries, sweet potatoes and watercress.

3. Calories from lean protein sources. When most people think protein, they immediately think "meat." Yes, meat certainly has protein, but unfortunately a lot of meat also has saturated fat and cholesterol. Not only does this add unwanted calories, but it also adds undesirable health effects, including increased risk of cardiovascular disease and cancer mortality. Protein is best supplied from lean sources, which include both animals and plants. Lean sources of animal protein include chicken breast, turkey breast, fish, egg whites and fat-free dairy. Plant-based protein is naturally lean and includes legumes, whole grains, nuts, soy and various vegetables. People often think animal-based protein is superior to plant-based proteins; however, a well-balanced plant-based diet can certainly provide an ample amount of protein. Not only are plants great sources of protein, they're also inexpensive and have a minimal impact on the environment compared to animal products. If you're not quite ready to give up your animal protein entirely, that's OK. Just be aware that plants are a great, sufficient supplement and alternative to a lean, animal-protein-rich meal.

4. Calories from healthy fats. All fats, whether unsaturated (" good") or saturated (bad), are high in calories. One gram of fat weighs in at 9 calories, whereas 1 gram of protein or carbohydrates weighs in at 4 calories. However, having calorie "baggage" doesn't mean you should avoid consuming all fatty foods, as fat is still a nutrient needed for normal body function. This simply means you want to get the healthiest, fattest bang for your buck. To do this, eat monounsaturated fats such as olive oil, avocados and nuts, and omega-3-loaded polyunsaturated fats such as walnuts, fish and flax. Further, steer clear of saturated fats like butter, as well as fatty cuts of meat such as beef and pork. Also avoid trans fats (partially hydrogenated oils) found in processed foods. According to the American Heart Association, Americans are eating less trans and saturated fats than they were three decades ago, but they're still consuming these bad fats more than what's recommended for good cardiovascular health. To keep your heart healthy, belly satisfied and waist slim, include an appropriate amount of healthy fats in your daily snacks and meals.

Finally, it's important to note that the foods with the least amount of calories come from the best sources (like the ones listed above). So if you want to lose, maintain or even gain weight, choose wisely, and choose calories that will do you good.

Christina Fedeli contributed to this blog.

Kristin Kirkpatrick, MS, RD, LD, is the manager of Wellness Nutrition Services at the Cleveland Clinic Wellness Institute. She is an experienced presenter, an award-winning dietitian, an author and a regular television guest on both local and national shows, as well a contributor to several national magazines and newspapers. The Huffington Post recently named Kristin "one of 25 diet and nutrition experts you need to follow on Twitter." Kirkpatrick's career began in Washington, D.C., lobbying for Medical Nutrition Therapy reform, and from there she went on to become the Regional Coordinator of the National Heart, Lung and Blood Institute's Hearts N Parks program in Maryland. Follow her on Twitter at @KristinKirkpat.