The most basic approach to weight loss is burning more calories than you consume. For instance, since 3,500 calories equals 1 pound of fat, a weight loss app—or even just a pen and paper—can help you decide how many calories you need to cut from your diet or burn at the gym in order to meet your goals. “If you were to burn 500 more calories per day 7 days a week, that would lead to 3,500 calories in a week and 1 pound of weight loss,” says Gagliardi.
"Stepping on the scale frequently makes you aware of small changes and helps you quickly react to those changes. The National Weight Control Registry, a large group of people who have successfully lost at least 30 pounds and kept it off for 5 years, found that successful 'losers' weigh themselves often and make adjustments accordingly. When you begin to understand that sodium, carb intake, hormones and alcohol intake can impact weight and that it isn't possible to gain 2 pounds of fat overnight, you will begin to better understand your body. The key is to pay attention to overall trends; don't obsess over day-to-day numbers! — Jennifer McDaniel, MS, RDN, CSSD, LD, food and nutrition expert
"Your body begins to work differently. This study proves that small amounts of nourishment throughout the day are better than the same amount of food concentrated in three big sittings. If we feed the body at regular intervals we send a signal to the body that it doesn't have to store calories. Conversely, when we skip meals we send just the opposite signal for the body to store calories, creating a negative effect on the metabolism." — Dr. Wayne Scott Andersen, co-founder and Medical Director at Take Shape For Life
Based on the concept of caloric density, which states that some foods have few calories in proportion to their size (say, a lettuce), while others have lots of calories packed in small portions (a regular chocolate chip cookie comes to mind), Volumetrics divides foods into 4 categories based on their calorie/volume ratio, and is perfect for people looking to binge on some foods while still shedding pounds. However, as with the calorie counting approach, Volumetrics does not take into account the quality of the calories, prioritizing quantity instead. The app Noom and Weight Watchers (both reviewed above) share similarities with this diet theory.