Fluid retention is also known as water retention. This term refers to an excessive build up of fluid in cavities, body tissues and circulatory system in your body. Our bodies consist of 70% of water. Water exists outside and inside of our body cells. Our organs, muscles and blood are mostly made up of water. Hormone – like substances which are complex system of prostaglandins and hormones are used by our bodies to regulate the water levels. When we intake excess water, then this can be resolved by our kidneys. They can excrete the excess fluid in our bodies in form of urine. If you have reduced hydration some day, then this can result in a decreased urine output than usual. Our bones are made up of about 50% water. The fat in our body consist of about 50% of water. Our muscles are made up of approximately 75% of water. In fact our body is made up to 70% of water. 
Symptoms of water retention
Here are the symptoms of water retention:
- When pressed the skin may hold the indent for a few seconds
- Joints may feel stiff
- Weight fluctuations
- Feeling stiffness or aching
- Bloated tummy – you will find it hard to fit in your favorite pair of jeans
Causes of water retention
This condition can occur for different reasons and in many areas of your body. Here are causes of water retention:
- Capillaries: The liquid (fluid) which is rich in oxygen, vitamins and nutrients continuously passes from our tiny blood vessels to surrounding tissues. This fluid is also known as tissue fluid (interstitial fluid). This fluid nourishes cells and makes them back to our capillaries. If the pressure inside of our capillaries changes, then can occur water retention. Also if something makes our capillary walls to leaky, then can happen water retention. 
- The lymphatic system: The lymphatic system consists of a network of vessels throughout our bodies. This system drains a fluid (lymph) from our tissues and it empties them back in our bloodstream. But if too much fluid is released, then our lymphatic system can be overwhelmed which means it cannot return the fluid fast enough and it will accumulate them around our tissues (this condition is known as fluid retention). 
- The heart: The pumping force of our heart is maintaining the normal pressure within the blood vessels. If there is a congestive heart failure (our heart starts to fail), then there are changes in our blood pressure which is a reason why we have serious water retention. In the most cases our ankles, feet and legs will swell. This fluid will also build up in our lungs which mean that we can have a long – term (chronic) cough. 
- The kidneys: Our kidneys are having complex function in our bodies. They remove the excess fluid material and waste out of our bodies. They excreted them from your body. The branches of the abdominal aorta are supplying the renal arteries with oxygen and blood. When they enter in our kidneys, then our blood goes throughout smaller and smaller blood vessels. The smallest blood vessels are the glomeruli (they are tiny capillary blood vessels and they are arranged in tufts). Our kidneys can eliminate the waste minerals from our body processes. If the urine outflow is obstructed, glomeruli or tubules are not working properly or the blood flow in our kidneys is affected, then can occur problems. Also if we have kidney failures, then the waste fluids and materials cannot be eliminated from your body which is resulting in water retention. 
- Pregnancy: During the pregnancy the weight of the uters on our major veins of the pelvis can lead to buildup of fluid. In the most cases this is not a serious condition and after the baby is born, this condition is resolved. 
- Physical inactivity: When we exercise, then we help to our leg veins to return the blood to our hearts (which is against the gravity). If the blood does not travel fast, then it begins to accumulate in the legs which lead to higher pressure in the capillaries. Because we have higher pressure in our legs, the fluid will leave the capillaries at a higher rate. Also this is a reason why fluids cannot come back later. Also if you have a long haul flights, then this can lead to increased risk of getting water retention. 
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