Hello and thanks for the question
There can actually be many causes for edema like this. The most conservative thought one would have is a high sodium diet and/or standing on your feet for prolonged periods of time. Taking medications like calcium channel blockers (given a lot for high blood pressure), diabetic medications, and estrogen (either from an overproduction from your own body, hormone replacement therapy or birth control pills). Other more serious causes include congestive heart failure (would be seen in the extremities), kidney disease, and venous insufficiency could cause this as well (in the leg area and ankles), also the lymphatic system . The lymphatic system clears helps clear excess fluids from the tissues....if this is not working correctly, the excess fluids will be noted. Given your age, and if you do not have any health problems, I would suggest watching the salt intake and propping your feet up at night. If the swelling persist, let your Dr know, and he/she can give you something to take by mouth for the water retention and will mostly run a few test.
Hope this helps!
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