Why do my ankles swell when i do not get enough sleep?

Fluid retention: If both ankles swell, the problem is not your ankles but your body retaining fluid. The 4 most common causes of fluid retention come from heart, lungs, liver or kidney. The only relationship that may be associated with less sleep is less time witih your feet elevated, so gravity brings the fluid down to your ankles. Try to keep them elevated during the day.