Some causes related to cardiovascular disease: Heart failure often produces weight gain as a result of fluid retention. Up to 10 - 12 pounds of fluid can be retained without producing visible edema.
Some causes related to other disorders: Endocrine disorders such as Cushings Disease or hypothyroidism can often produce weight gain, as can kidney or liver disease.
Significance: Weight gain that is truly unexplained, and is not accompanied by a gain in fatty tissue, needs to be evaluated medically.
