An apple a day keeps the doctor away, but three or four might not keep extra pounds at bay. All fruits contain calories or energy that you need for basic functions such as respiration, temperature regulation and digestion, as well as any physical activity you perform. Calling fruit fattening might mislead you into thinking that fruits automatically make you fat, but it is caloric surplus that packs on the pounds, not nutrients intrinsic to any one kind of fruit.
A healthy diet is one high in fresh fruits and vegetables, according to the Centers for Disease Control and Prevention. Whole fruits help your digestion and might play a role in preventing certain diseases, such as stroke and cardiovascular disease. All fruits contain fiber, but removing the skins from fruits such as peaches and pears reduces the amount of fiber in each serving. Eating organic fruits lets you eat the whole fruit without worrying about pesticides on the skins of the fruits.
Fruits are carbohydrates and contain simple sugars called fructose. The fructose contained in fruits is chemically the same as the fructose contained in some sugary snacks and soft drinks, but fruits deliver energy in a nutrient-dense package. You get more dietary benefit from the caloric intake in fresh fruits than you do in cotton candy or cola. Citrus fruits, guava, mangoes and melons contain high levels of vitamin C, and prunes and bananas offer potassium, which play important roles in maintaining a healthy immune system and a regular heartbeat, respectively.
Too much food of any kind can lead to excess calories and eventual weight gain. Understanding daily dietary requirements helps you analyze your caloric needs and limits. A 35-year-old woman who exercises between 30 and 60 minutes a day need 2 cups of fruit based on a 2,000-calorie diet, and a 25-year-old man who exercises more than 60 minutes every day needs 2 1/2 cups of fruit per day based on a 3,000-calorie diet, as calculated by the Centers for Disease Control and Prevention.
Certain fruits are more energy-dense than others. A serving of fruit that contains 15 grams of carbohydrates and 60 calories is the equivalent of 1 cup of honeydew melon, cantaloupe or raspberries, but just 1/2 cup of mango or three prunes. You can eat 1 1/4 cups of strawberries or watermelon and add only 60 calories to your daily intake, or substitute a small apple, or an extra-small, 4-oz. banana.