Those mice showed far lower weight gain and body fat than those fed the same high fat diet, and even lower than mice that were more active.

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If you eat more calories than you burn, usually you will gain weight as the body stores the excess.

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The study shows that if you increase drinking sugary beverages by one serving per day, it will lead you to gain an additional pound of body weight over four years.

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As they age rapidly, these children suffer from a loss of body fat and hair and an inability to gain weight.

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Two years after her wedding and still not pregnant, the 26-year-old visited a gynecologist, who diagnosed her with polycystic ovary syndrome, an endocrine disorder that can cause women to stop ovulating, gain unusual weight, develop irregular periods or skin problems and grow abnormal facial and body hair.

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Patients often gain a lot of weight, and the ups and downs in fluid buildup stress the body and heart.

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The fact that the body image of the women's fathers appears to have no impact further suggests that lifestyle rather than genes influences weight gain.

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