Does Metabolism Matter in Weight Loss?

Do you know people who complain about having a slow metabolism and how they barely eat anything yet still gain weight? Or have you met people who complain about someone they know who can eat whatever he or she wants — including large portions of junk food — due to a fast metabolism and apparently never gain weight. In both cases the individual usually ends by saying, "It's not fair!" These scenarios raise several very good questions:

  • What role exactly does metabolism play in weight gain or weight loss?
  • Is your metabolic rate determined by your genes? If so, can you speed up a slow metabolism through exercise, drugs or certain foods?
  • Is the importance of metabolism just a myth? Is weight gain or loss purely due to "calories in and calories out?"

The answer to these questions involves a mix of nature (genetic make-up) and nurture (the environment).

What Is Metabolism?

Metabolism or metabolic rate is defined as the series of chemical reactions in a living organism that create and break down energy necessary for life. More simply, it's the rate at which your body expends energy or burns calories.

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