The first thing you want to look for is the serving size and servings per container, so you know what type of portion you are working with. Pay extra attention to servings per container if you’re buying an individually packaged food (like chips, a candy bar, or trail mix), as they are often 2-4 servings per package.
Next look at calories. As a rule of thumb, try to limit foods that are high in calories but small in serving size. For example, ¼ cup of Naked Granola, or about 1 large handful, is 150 calories. That’s the same amount of calories in a banana and 1 tablespoon of peanut butter, which will be more filling. Note that whole nuts are the exception to this rule, as while they are energy dense, they also contribute to satiety and provide healthy fats, protein and vitamins.
Now look at fat. Avoid packaged foods high in saturated fat and anything containing trans fat. Opt for foods moderate in fat or higher in poly and mono unsaturated fats. Examples include almonds, salmon and guacamole. If you’re looking for a snack to eat within an hour of starting a workout, choose something lower in total fat, as a higher-fat snack before exercising could cause stomach pain and discomfort.
Finally, check the carbohydrate, sugar and fiber content. Ideally, you want a food that is lower in sugar and higher in dietary fiber (men need 38 g and women 25 g of fiber per day). It is recommended that most people get less than 30 g of sugar per day, so try to pick foods with less than 5-10 g of sugar per serving. And if you are eating within one to two hours of beginning a workout, choose something a little lower in fiber (less than 5 g total) as this can, along with fat, cause stomach discomfort during the workout.