It is important to understand that weight is entirely a function of input and output. The input is the food you eat and the calories contained therein. The output is your energy output. To lose weight the output needs to be greater than the input. It is that simple. Do not believe any of the diet fads. If you are currently not gaining or losing weight then just burning 300 extra calories per week or eating/drinking 300 calories less per week (2 sodas for example or a small burger) WILL make you lose weight - in this case around 5 pounds of fat per year.
In a new study, Stanford University researchers put more than 600 overweight adults on either a healthy low-fat or low-carb diet. It turns out, participants had similar levels of weight loss success on each plan. Researchers looked for clues (such as insulin levels and gene patterns) to see if there are any factors that might make someone more successful on either diet, but after combing through the data, they were not able to make any connections. Since it may take years before scientists discover individual traits that could lead to more success on one plan compared to another, for now, we can learn a lot — and lose a lot! — by recognizing the dieting advice that all experts agree on.
In a way, moderate-intensity physical activity is that "magic pill" a lot of people are looking for, because the health benefits go beyond keeping your waistline trim: Not only can it reduce your risk of cancer, stroke, diabetes and heart attacks, but studies have shown that physical activity can significantly improve the moods of patients with major depressive disorders.