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It is a law of physics---burn more calories than you consume---inexorable to lose weight. The hardest way is to eat less only. A more sustainable way is to exercise more combined with eating less calorie-dense food choices, but allowing yourself some "forbidden" foods in small quantities once in a while to slake the psychological craving.
Very simple, no big trick: exercise more and eat less = lose weight
Not to take away from your comment, one of the challenges people hoping to loose weight suffer from is the
very simple, no big trick mentality. The simple truth is that you have to consume fewer calories than you burn to loose weight, but "the truth, the whole truth" is much, much more complex.
The simplified view of metabolism suggests people have a set point somewhere, a "high" or "low" metabolism that they are genetically programmed for. The truth is much more complex; the body's metabolism is an intricate dance that's controlled by hormones created in the intestines, pancreas, thyroid, liver, adrenal glands, and by the same fat cells we're trying to reduce in size, and this hormone brew has a dramatic effect on both how quickly or slowly we burn calories and on how much or little we crave calories.
I'll give you two quick examples that demonstrate how variable our metabolisms are: breakfast and exercise.
Research into weight loss shows that people who eat a healthy breakfast are more likely to maintain a healthy weight than people who skip breakfast, even they consume the same number of calories. The same phenomenon occurs when people involve themselves in heavy exercise and don't eat shortly after they finish their workout: people who consume a healthy snack after they workout are more likely to maintain or loose weight than people who don't, even though they consume
more total calories.
Both these examples demonstrate that there is some complex metabolic calculus going on beneath our skin. So, while the
simple truth is that you'll loose weight if you just eat fewer calories than your body burns is true, the
whole truth is that it's not just how much you eat and exercise, but also what, when, and how you eat and exercise, and those what, when, and hows vary from person to person.