Edema is noticeable swelling that occurs from fluid build-up in body tissue. Specifically, excess fluid will build up in blood vessels as well as in interstitial spaces. Edema usually occurs in the feet, ankles and legs.
There are many different types of Edema though. Anasarca is a type of edema that affects all tissues of the body equally while macular edema affects just the eyes. There are many more forms of edema but our focus is only on the feet, ankles and legs which fall under the category of peripheral edema.
Too much salt intake can lead to edema. When the body has too much salt in it the body will then perceive a need for more fluid and will end up generating excess fluids which can likely lead to edema. Pregnant women also get edema fairly often. This is because the body produces a considerable amount of excess blood and fluid to help support the developing baby and, for certain periods, this can lead to edema.
Causes
Edema is caused by extreme fluid retention in the body. There are a litany of reasons this might occur such as pregnancy or high salt in-take. Edema can also be caused by remaining in one position for too long such as sitting, although, it would need to be an extremely long time for a healthy person. Some medications can also help cause edema as a side effect such as steroids and certain high blood pressure drugs.
First Aid & Prevention
Prevention is fairly simple - consume a healthy diet that is low in salt and avoid prolonged periods of inactivity as much as you can. If you do have edema, you should see a doctor if pitting is occurring. Pitting is when pressure applied to the skin of the swollen area is released and an indentation is left behind. You should also see a doctor if you are experiencing any sort of pain in your chest or are having any sort of difficulty breathing.