Use less of a “regular” dressing to shave calories, fat and salt. Unless you like dry salads, then use no dressing and enjoy! Low Calorie Fast Food Tip #3 -- The USDA recommends 2,300 mg of sodium per day for healthy adults; 1,500 mg for older folks, African-Americans and people with high blood pressure. Low Calorie Fast Food Tip #4 -- There are several strategies you can use to reduce calories, fat and sodium.