But they argue that this is probably because they inadvertently consume fewer calories, rather than because of the mechanism suggested by Dr Atkins whereby the body switches from a carbohydrate-burning metabolism to a mainly fat-burning metabolism.

ECONOMIST: Dieting

Secondly, losing weight too quickly when you don't have a significant amount of weight to lose can result in muscle loss as well as fat loss, which can decrease your metabolism and make it more difficult to maintain your weight loss.

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In a study published in the American Journal of Clinical Nutrition, green tea extract increased energy expenditure, which is a measure of metabolism, plus it had a significant effect on fat oxidation, or how much fat your body burns.

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Beta carotene is a type of carotenoid, a plant pigment that is a provitamin for vitamin A. During its digestion and metabolism, a percentage is converted to vitamin A, a fat-soluble vitamin that is important for vision, growth and development, and healthy immune and reproductive function.

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Individual metabolism is not something governments can control (not yet), nor can they isolate the fat input from the rest of the diet, much less unknowns such as genetics, lifestyle, and exercise regimens.

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