All You Need to Know About Water Retention

water retention

We all know that our bodies are largely made up of water.  Water is essential for all our systems to function properly [1].  But when we are talking about water retention, we aren’t talking about drinking water and it’s flowing directly into our ankles and swelling them up like balloons, which is why one of the best ways to improve symptoms of water retention is to drink more water.  What we refer to as “water” when discussing water retention is actually a clear, watery fluid that is found in the cavities and tissues in our body.  At times things don’t go perfectly and our bodies hang onto some of the water that should naturally be flushed out of our systems.  This is when we get water retention or fluid retention that causes swelling, often referred to as edema [2].

Water retention can happen for a variety of reasons, including injury, organ failure, pregnancy, stagnancy, lack of certain minerals, premenstrual syndrome, pregnancy or poor diet.  The result of the water retention can lead to edema in a variety of areas of our body most often the limbs including feet, ankles, legs and hands [2].  At times, when an issue is severe, fluid retention can cause swelling of the face or abdomen.  How we treat water retention depends on the underlying cause.  Changes in diet, exercise, increased water intake, or medications are all things that can be used to treat fluid retention.  Fluid retention can be unsightly and uncomfortable but is usually not something to worry about.  However, if water retention is prolonged or severe, it can be a sign of an underlying problem and should be brought to the attention of your physician.

What is Water Retention?

When our bodies are function as intended, vitamin and oxygen rich fluid passes from our capillaries to our tissue.  This fluid nourishes our cells and then returns to our capillaries where it is then processed through our lymphatic system or kidneys and flushed out of our bodies as urine.  Sometimes excess fluid can leak out of the capillaries and typically this is where our lymphatic system kicks in.  The lymphatic system acts as a back-up or system overflow control and can catch and return a lot of the leaked or excess fluid back to the bloodstream [3].

Water retention is essentially what happens when this process doesn’t go smoothly, and rather than the excess fluid being flushed out, it builds up in our joints or tissue [2].  This can happen to us frequently without any signs or symptoms and we really don’t know that it’s going on.  It becomes a problem when so much fluid leaks and builds up in the tissues that it causes swelling.  While swelling in and of itself really isn’t anything to worry about, the cause of the fluid retention and swelling is something to consider.

Most commonly we retain water and see swelling in our feet, ankles and legs.  There are two main reasons for this.  One is that gravity naturally pulls the excess water down to our extremities.  Two, our feet and ankles are farthest away from our heart so sometimes weakening of blood vessels means that it’s harder for the body to push blood all the way back up to the heart from the legs, so the water settles there.   Some mild swelling in the feet and ankles can be normal under certain conditions like when you are dealing with extreme heat or during pregnancy.  However, if it happens frequently it may be one of the first signs that something within our bodies is not functioning properly.

What Causes Water Retention?

The main thing to remember when talking about water retention is that it is all about blood flow.  We discussed the capillaries carrying vitamin and oxygen rich fluid to our tissues.  This means all our tissues, from heart to lungs to skin, essentially everything.  So, when that blood flow is interrupted for some reason that’s where we get into issues of fluid leakage and water retention.

Some of the main common reasons for water retention include:

  • Weakening of the capillary walls. If there is a weakening of the capillary walls, then the fluid can leak out.  If there is a lot of weakening and fluid leakage, then that’s when water retention occurs as the fluid leaks at a faster rate than it can be processed and returned to the blood stream.
  • Problems with the lymphatic system. The lymphatic system processes excess fluid and returns it to the blood stream.  If there is an excessive amount of fluid sometimes the lymphatic system can’t keep up, as mentioned above.  However, sometimes there is a problem with the lymphatic system such as it not being formed properly, being damaged due to surgery, or because of diseases like cancer.  In this case the lymphatic system can’t work properly, and water retention can occur.
  • Heart disease. Congestive heart failure occurs when the heart does not pump normally so there is not enough pressure to move the blood fluids in and out of the heart properly [4].  When this happens water retention occurs not only in the feet, ankles and legs but can happen in the lungs and around the heart.  In addition to the swelling a cough might develop because of excess fluid.  This type of water retention is something to bring to the attention of your doctor.
  • Kidney failure. The kidneys help filter all our blood and fluids.  When the kidneys don’t work the way they are supposed to they can’t filter the fluid out of the blood.  In turn they can’t convert it to urine to be excreted by the body and as such, water retention and swelling occurs.
  • Pregnancy. There are several reasons why water retention happens during pregnancy.  One is that the excess weight of the uterus puts pressure on the veins and capillaries and therefore they can’t transport blood and fluid as effectively as they should.  This can cause the water leakage we talked about and in turn water retention.  The more common reason is that the body increases blood and fluid production by almost 50% during pregnancy to support the body and nourish the baby [5].  Sometimes our bodies just can’t keep up with this extra fluid production and therefore we get water retention and swelling.  This is really a normal part of pregnancy and helps to cushion our bodies and lubricate our pelvic joints to get ready for birth.  Any sudden severe swelling, especially in the face during pregnancy can be a sign of a condition called pre-eclampsia and should be brought to the attention of your OBGYN immediately.
  • Premenstrual syndrome. Hormones fluctuate during a woman’s menstrual cycle and increased hormones can trigger increased fluid production.  Often this excess fluid is stored in the breasts in the week leading up to menstruation and is flushed from the body naturally as menstruation begins.  While it can be frustrating and often uncomfortable, it is a normal part of a woman’s monthly cycle.
  • Lack of exercise. Our bodies need muscle stimulation to keep blood flowing and to stimulate lymphatic function.  When we are stagnant or idle our blood doesn’t flow the way it should, and our bodies can start retaining water.  Therefore, you might experience swelling in the feet or ankles at the end of a long work day or after a long flight.  It’s also why patients on bed rest are exercised, placed in compression socks, or placed in mechanical units that automatically tighten around the legs and ankles and release at various times of the day, and checked often for edema.
  • Dietary issues. A lack of or excess of certain nutrients can lead to water retention. Protein attracts water and helps with water balance.  When there is a severe protein deficiency there isn’t enough protein to attract the water from the tissues and saturation can occur.  You can learn more about the benefits of protein This is where we see a swollen abdomen.  Magnesium, vitamin B6 and potassium are all important in helping functions of our circulatory system when these are deficient water retention can occur [6] [7].  Salt (sodium) binds to water and thus excess salt causes us to retain water and can cause swelling.

How Can Water Retention be Treated?

waterThe treatment for water retention really depends on the cause.  If the cause is weakening capillaries for example, you don’t want to treat with a diuretic which increases water production and can cause more problems.  If it’s not caused by a vitamin or mineral deficiency, then you wouldn’t treat with supplements.  There isn’t a one size fits all approach to treating water retention.  However, there are some specific things that can be done to treat and prevent water retention:

  • Drink water. Drinking water might seem counter intuitive to avoiding water retention.  However, the water we drink is not the same as the water that’s being retained in our joints and tissues.  Drinking water helps our body function the way it is supposed to.  It gives a kick start to our systems and helps our bodies flush excess fluid and aids the kidney’s in processing it out [3].
  • Eat a well-balanced diet.  Diets rich in potassium, vitamin B6, magnesium and protein all help keep our systems functioning properly.  Magnesium helps reduce water retention particularly in premenstrual women [8].  Vitamin B6 helps to form red blood cells [9].  Healthy cells can transport fluids more efficiently.  Potassium decreases sodium levels [10] and increases urine production.  Foods like bananas, potatoes, nuts, whole grains, dark chocolate, avocados and tomatoes are a good place to start.  Avoiding refined carbs like sugar and white flour also helps to avoid spikes in insulin levels which causes the body to retain sodium. As mentioned above sodium binds to water causing fluid retention.
  • Even moderate amounts of exercise can help reduce fluid retention.  Anything that helps get the blood flowing and circulating can help [1] [7].  For bed ridden patients this can be ankle rolls, arm raises, mild stretching, or leg raises.  For those that sit at an office all day or someone taking a long flight, just getting up and walking up and down the aisle or hallway for a bit helps.  Any sort of moving, stretching, or wiggling is beneficial.  For those that are looking for a more serious work out, check out this information about HIIT training.
  • For specific conditions like heart disease or kidney failure diuretics can be prescribed [10].  Diuretics, known as “water pills” cause your body to release more sodium into your urine.  As sodium attracts water, it can pull water from your blood thus decreasing the amount of fluid you retain.

Water Retention Overview

The key take aways to remember are that water retention is something that is extremely common and most of the time not something to worry about.  Frequent or excess swelling caused by water retention is something to get checked out by your physician.  A healthy, well balanced diet that includes foods rich in potassium and magnesium and low in sodium can help decrease water retention. Exercise is key in helping to keep our blood flowing properly and keeping water retention at bay.  Drinking plenty of water is good for all our bodily systems and will not cause more fluid retention, in fact, it helps flush excess fluid [11].



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    Barry M. Popkin, Kristen E. D’Anci, and Irwin H. Rosenberg Nutr Rev. 2010 Aug; 68(8): 439–458. doi: 10.1111/j.1753-4887.2010.00304.x
  2. Causes and Signs of Edema
    © IQWiG (Institute for Quality and Efficiency in Health Care)
  3. How Do the Kidneys Work?
    PubMed Health Glossary (Source: NIH – National Cancer Institute)
  4. Heart Failure
    PubMed Health Glossary (Source: NIH – National Institute of Diabetes and Digestive and Kidney Diseases)
  5. Physiological Changes in Pregnancy
    Priya Soma-Pillay, MB ChB, MMed (O et G) Pret, FCOG, Cert (Maternal and Foetal Med) SA, Nelson-Piercy Catherine, MA, FRCP, FRCOG, Heli Tolppanen, MD, Alexandre Mebazaa, MD, Heli Tolppanen, MD, and Alexandre Mebazaa, MD Cardiovasc J Afr. 2016 Mar-Apr; 27(2): 89–94.
    doi: 10.5830/CVJA-2016-021
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  8. Effects of Magnesium and Vitamin B6 on the Severity of Premenstrual Syndrome Symptoms
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    Pregnancy and Birth: Overview
    © IQWiG (Institute for Quality and Efficiency in Health Care)
    How Does the Menstrual Cycle Work?
    © IQWiG (Institute for Quality and Efficiency in Health Care)
  • Weakening of the capillary walls. If there is a weakening of the capillary walls, then the fluid can leak out [4]. – i cant find anything for this statement. I did find Systemic Capillary leak syndrome.. Its a condition which fluid and proteins leak out of tiny blood vessels and the cause is unknown.. I also tried google, got the same answer
  • Often this excess fluid is stored in the breasts in the week leading up to menstruation and is flushed from the body naturally as menstruation begins – I was able to find it in wikipedia, but not in NCBI
  • Potassium increases urine production – i cant find it in NCBI.
    I found this on
    A potassium level that is too high or too low can be serious. Abnormal levels may cause symptoms such as muscle cramps or weakness, nausea, diarrhea, or frequent urination.
  • Even moderate amounts of exercise can help reduce fluid retention. Anything that helps get the blood flowing and circulating can help [1] [8]. – it’s on number 1 and 9 but what was written on NCBI is intense exercise can help with fluid balance.

I found this statement on
Moderate exercise on a regular basis can also help relieve many ailments in addition to water retention such as insomnia, back pain and lethargy.

One comment

  1. Rosemary Borzell

    This article leaves out medications as cause of water retention.

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