5 Surprising Truths About Calories

If you've been trying to lose weight, you've probably heard this rule: It's just a matter of calories in, calories out. That is, simply burn more calories than you consume, and the pounds will melt off. Right? Well, not exactly.

If you are trying to lose weight, then you know that it's not that simple-or that easy.

It turns out, some calories count more than others. Sure, there are 100 calories in two tablespoons of chocolate chips, and the very same 100 calories in broccoli. But there's a huge difference in the way that they affect your appetite, your energy level, and your long-term health.

Here are 5 surprising things you didn't know about calories:

RELATED: Learn the 5 Ways to Keep Calories in Check

LOOK FOR COLORS About half of each meal should be fruits and vegetables. Not only are they low in calories, high in fiber, and filling, but a wide variety of produce will provide nutrients and minerals that help stave off diseases like cancer, and keep your bones, muscles, metabolism, heart, and lungs in top form. Dark green veggies like kale and spinach will give you iron--to maintain health of red blood cells, which deliver oxygen-rich blood to the body; oranges and strawberries provide vitamin C to help the body absorb the iron. Red tomatoes and peppers have vitamin C, lycopene, lutein, potassium, beta-carotene, and vitamin B6. Blueberries, blackberries, beets, and eggplants are sources of potassium--which helps the muscles contract properly--and anthocyanins, which help prevent cancer. Orange and yellow fruits and vegetables like corn, butternut squash, pineapple, yellow peppers, mangos, carrots, pumpkins, sweet potatoes, and apricots are rich in beta-carotene, lutein, potassium, manganese, copper, folate, and vitamins C, A, and B6.

LOOK BEYOND LABELS. Often products that sound healthy are junk foods in disguise. For instance, a Banana Berry smoothie from Jamba Juice has 400 calories and 82 grams of sugar--as much as four Mounds bars. Even Yoplait Original 99% Fat Free Lemon Burst Yogurt has 180 calories and 30 grams of sugar. Not even all chocolate is created equal. A Hershey's Milk Chocolate Bar, for instance, has 210 calories, 24 grams of sugar, and 13 grams of fat compared with Chocolove's Extra Strong Dark Chocolate--with 77% cocoa, which has 170 calories, 11 grams of carbs, and six grams of sugar in a 30-gram serving. Look for varieties that are 70% cocoa or higher for the least amount of sugar and the most antioxidants, which have been shown to reduce high blood pressure and inflammation.

PLUS: Learn to Decode Your Entire Nutrition Label

FIND THE FIBER. Found in fruits, vegetables, beans, and whole grains, fiber fills you up fast with fewer calories, and because it takes longer to eat and digest, it keeps you feeling satisfied longer. Aim for 25 to 35 grams of fiber each day. Spread your fiber intake throughout the day, and try to consume at least five grams of fiber per meal. Water-soluble fiber, found mostly in fruits, vegetables, and beans, helps lower cholesterol and blood-sugar levels. Insoluble fiber, found mostly in whole grains--keeps the colon clean, which may help prevent cancer and digestive disorders. To avoid an upset stomach, be sure to get the timing right. It takes about two hours for fiber to leave the stomach and get to the intestine. So save high-fiber foods for after your workouts, or at least two hours beforehand.

DON'T FEAR FAT. There has been a flood of low-fat and fat-free products into the market in recent years. But we now know that unsaturated fats like the ones you can get from olive oil, avocados, canola oil, nuts, seeds, and almonds--actually help boost your heart health. They also leave you feeling fuller for longer and even lower risk of injuries like stress fractures. Stay away from saturated fat and trans fat; they raise your "bad" cholesterol levels and decrease your "good" cholesterol levels, and that can raise your risk for heart disease. You still want to keep fats in moderation. (Plus: Get more advice about the difference between good and bad fat.)

WATCH THE SUGAR Sure, those Skittles seem harmless enough-after all, one bag has only 250 calories and 2.5 grams of fat. That sounds pretty tame for candy. But the 47 grams of sugar per serving has a cascade of negative side effects: You'll get a sugar high and crash that will send your energy levels on a rollercoaster ride and set the stage for more craving down the line. Indulging those cravings can lead to weight gain and health problems like type 2 diabetes and high blood pressure. Look for products with the fewest grams of sugar, and aim for less than 2.5 grams of sugar/100 calories. The World Health Organization recommends keeping sugar intake to no more than 10% of daily calories. For many folks that's a limit of 50 grams of sugar per day. Aim much lower if you're trying to shed pounds. Your best source of sugar is fresh fruit, which provides vitamins and minerals, along with fiber. If you must indulge in candy, enjoy it right after a tough workout. In the 20 to 30 minutes immediately following a run that's longer or faster than you usually go, your body is especially efficient at metabolizing sugar. In fact, pairing these carbs with protein will help your muscles recover.

PLUS: 10 Ways to Make Your Favorite Meals Healthier

Here are two ways to figure out whether a product has sugar.

1. Check the ingredients. The ingredient list is usually printed below the Nutrition Facts panel. Below is a list of different names for different types of sugar:

Corn syrup
Corn sugar
High fructose corn syrup
Maltodextrin
Sucrose
Dextrose
Honey
Molasses
Turbinado sugar
Brown sugar

2. Look at the order. Ingredients are ordered by weight, so the ingredient that is listed first makes up a greater percentage of the product compared with the last ingredient listed. If sugar (or one of the other sources) is listed as one of the first two or three ingredients, you know that the food is high in sugar.

Written by Pamela Nisevich Bede, M.S., R.D.

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