下面文章中有5处需要添加小标题。请从以下选项（A,B,C,D,E和F）中选出符合各段意思的小标题。 A.Get adequate iron B. Keep yourself hydrated. C. Get enough calories D. A little exercise goes a long way. E. Eat a balanced, varied diet F. Spread your calories throughout the day. The Energy Diet How can I lose weight when every time I go on a diet, I'm so exhausted that I can barely make it through the day? So goes the complaint of many men and women who are concerned about being overweight. What many people don't realize is that a healthful weight-loss plan can actually boost your energy. The key is to eat smart. And then combine this healthful diet with some physical activity. Here are six pointers to get you started. 1.____ Consume too few calories and you'll have less energy, and decrease the amount of calories burned. 'That's because one of the ways the body protects itself from starvation is to slow down its metabolism,' explains Dr. Donald Hensrud, a nutrition professor at the Mayo Clinic, in Rochester, Minn. So how many calories do you need to feel energized while also slimming down? A healthful weight-loss rate is roughly one-and-a-half pounds per week, and the calorie intake to achieve this depends on your age, weight, and activity level. 2.____ The key to keeping your energy level up when you diet is to eat balanced meals that supply all the nutrients you need. 'Vitamins and minerals act like spark plugs,' explains Kristine Clark, director of sports nutrition at Pennsylvania State University. 'They help release the energy in nutrient-rich food.' Try to follow USDA guidelines. They call for 6 to 11 servings per day from the bread, cereal, rice, and pasta group; three to five servings of vegetables; two to four of fruits; two or three of milk or cheese; two or three of meat, fish, or eggs. Avoid fried and creamy dishes, and keep consumption of sweets and desserts to a minimum. 3____ When you go for five to six hours without food, the amount of fuel in your system starts to run low, and you begin to feel tired. Therefore, says Kristine Clark, it's important to eat at regular intervals to keep your energy up. If you exercise, it's important to make sure you have 'fuel in the tank' before you head for the gym. Avoid eating a large number of calories at one time, since it's harder to control your total calorie intake, making weight gain more likely. 4____ About 10% of women of childbearing age in the United States are iron deficient. Iron is essential for energy and endurance because it is a vital component of red blood cells, which carry oxygen to working muscles. 'Fatigue and listlessness can be directly associated with too little iron,' says Frances Berg, a licensed nutritionist in Hettinger, N.D. The best sources of iron are meat, poultry, and some fish. Other sources: fortified cereals, dried beans, dried fruits, and peas. 5____ 'I don't have the energy to exercise!' say many dieters. Indeed, a 1998 survey, developed in part by the Center for Sports Medicine at Penn State, found that over 70% of respondents cited 'too tired' or 'lack of energy' as key reasons to skip exercising. Yet exercise is exactly what these people need. And, lastly, don't try to do too much too soon. Consider breaking your exercise into small units. Instead of trying to do 30 minutes in one chunk, accumulate exercise in short bouts （一场，一回）every day by mowing the lawn, walking to work, or climbing stairs instead of taking an elevator. It won't be long before you reap （收获）the rewards. Imagine carrying a 15-pound sack of groceries around all day. Then think about how much more energy you'd have if you put that sack down.