Add 10 percent to the amount of daily calories you think you’re eating. If you think you’re consuming 1,700 calories a day and don’t understand why you’re not losing weight, add another 170 calories to your guesstimate. Chances are, the new number is more accurate. Adjust your eating habits accordingly. For instance, your cup of coffee might have more calories than you thought. Write down what you eat for one week, and you will lose weight. Studies found that people who keep food diaries wind up eating about 15 percent less food than those who don’t. Watch out for weekends: A University of North Carolina study found people tend to consume an extra 115 calories per weekend day, primarily from alcohol and fat.