Water retention is a problem in which the kidneys retain fluids, causing sudden weight gain. The water is deposited in ankles, legs and other body parts. The main causes of water retention are kidney disease, heart problems, premenstrual syndrome, liver disease and thyroid problems. Insufficient intake of water can also cause this problem. Excess consumption of salty foods can cause water retention. If you have water retention, you should elevate the legs. Apply ice pack on the ankles. Eat diuretic foods like cabbage and cranberry juice. Home cures can help in curing the problem of water retention very effectively. 17 best home cures for water retention are as follows.