Any abnormal accumulation of fluid in tissues or cavities of the body; waterlogging of the tissues due to excessive loss of plasma through the capillary walls. It may be generalized (the condition once known as dropsy or hydrops) or confined to one area, such as the ankles. Also known as water retention.

Persons most commonly affected: All age groups and both sexes.
Organ or part of body involved: Tissues or cavities of the body.
Symptoms and indications: Swollen ankles and legs and, often, breathlessness. Pressing the skin leaves an indentation for a few moments.
Causes and risk factors: Renal failure, cirrhosis, heart failure, malnutrition or starvation, certain types of gastroenteritis, thyroid disease, and venous insufficiency, or weakened veins.
Prevention: Keeping legs elevated as much as possible, cutting down on salt intake, exercise, loosing weight and wearing supportive stockings. 

Eat foods that stimulate the elimination of water such as horseradish, celery, nettle, beetroot and sorrel.