If dieting is leaving you without energy for workouts or daily tasks, it is time to re-examine your plan. Setting unrealistic calorie goals or feeding yourself the wrong kinds of food can lead to irritability and significant drops in energy. Consider making some tweaks to your diet plan to invigorate your body and make your plan more manageable.
Eat at least 1,200 calories per day if you are a woman and 1,500 calories per day if you are a man. Eat fewer calories, and you might experience dips in your energy as your body slows down -- and hangs onto fat for self preservation. If you are trying to lose weight quickly, slow down your expectations and aim to lose just 1 to 2 lbs. a week.
Make the calories you do eat come from quality, nutritious foods. Do not waste your calories on small portions of junk food and sugary treats. Aim to include at least the minimum portions from each of the food groups put forth in the USDA Food Guide Pyramid. Go for a minimum of six servings of grains, with half coming from whole grains; 5.5 oz. of lean proteins; 3 cups of dairy; 2 cups of vegetables; 1 ½ cups of fruit; and 5 tsp. of oils. Limiting any one of these food groups can lead to dips in your energy and nutritional deficiencies.
Eat a breakfast that combines lean proteins and healthy carbs to kick-start your energy for the day and prevent morning sluggishness. Try oatmeal with skim milk and berries, egg whites scrambled with veggies and low-fat cheese or plain yogurt mixed with shredded wheat and bananas.
Curb your caffeine intake. Stop drinking caffeine in the mid-afternoon, as it might be preventing you from experiencing a good night's sleep – leaving you groggy the next day. Caffeine can remain in your body for 8 to 15 hours. Allow yourself an energizing snack midday, such as a handful of almonds, a fruit smoothie or one-half of a turkey sandwich on whole wheat bread, instead of a diet soda or cup of coffee.
Although you might feel you do not have the energy to work out, staying physically active might actually help boost your energy. Take a walk or attend a dance class to increase blood flow. At the other extreme, if you are exercising two or three hours per day in an effort to lose weight, you might be overtraining, which can lead to loss of energy. Take a few days off and try for a more moderate schedule if this is the case.
If adding more calories still leaves you listless, consult your physician to make sure you are not suffering from some underlying condition.