While fish are very efficient machines (unlike chickens and cows, they don't use metabolic energy by growing strong bones to fight gravity), they still eat a lot.

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These may include having a low metabolic rate in ecosystems where energy is in short supply.

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The loss in weight and body mass is driven by a metabolic disease manifested by increased energy consumption.

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We also know that smoking is a thermogenic agent, meaning that nicotine raises the rate of energy expenditure, metabolic rate.

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Lean body mass is the primary determinant of your metabolic rate how much energy (calories) your body uses each day.

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