Science-Based Side Effects Of Drinking Too Much Water

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Water makes up 60% of a man’s body and 55% of a woman’s.1 But as you are constantly losing water through sweating, breathing, and digestion, you need to drink plenty of water to maintain the water levels. But did you know side effects of drinking too much water are no less scary than those of drinking too little?

Fun fact: Your bones contain 31% water.

So how much water is too much water? Though most health professionals recommend 8 glasses measuring 8 ounces, which equals about 2 liters, or half a gallon, there is no real consensus. You should drink as much as you need to. So, here’s what you need to about the effects of drinking too much water.

1. Swells Up Your Cells

Drinking Too Much Water Can Swells Up Your Cells

Your body has free sodium and potassium ions. These act as electrolytes in the body and maintain fluid balance between your cells and your blood. When there is excess water in the blood, the concentration of these electrolytes dips which results in water from the blood stream flowing into the cells. This causes the cells to swell which can be dangerous for the body.

2. Hypokalemia Or Potassium Loss

Drinking too much water can lower potassium levels may cause hypokalemia

Potassium plays an important role in maintaining fluid balance in the body. Overhydration causes your body to expel more water through sweat or urine which can lower potassium levels in the body. Loss of potassium levels may cause hypokalemia, the symptoms of which could be such as vomiting, low blood pressure, paralysis, nausea, and diarrhea.

3. Strains The Heart

Drinking too much water can put undue strain on your heart

Your body has an effective water absorption mechanism. Almost 80% of the fluids you drink are absorbed by the small intestine through a process called osmosis. Water then enters the blood stream hereby increasing the overall volume of your blood. Drinking too much water can put undue strain on your heart due to the increase in blood volume and also lead to seizures in some cases.

4. You Might Get Headaches

Drinking too much of water can affect your brain

Drinking too much water over a short period of time can have a serious impact on your brain. An excess of fluid in the blood reduces the concentration of electrolytes. This leads to increased fluid flow into the cells including the cells in your brain. If you’re drinking more water and are also suffering from headaches, it could be a sign of overhydration. In severe cases, it’s best to seek medical help immediately.

5. Increases Urination

Drinking too much of water increases urination

The body has an efficient internal mechanism to maintain water balance and remove excess water through urination. Your body is not designed to hold more water than it needs, and hence all the extra fluid is expelled. This will lead to excessive urination or you will feel the need to urinate more frequently.

6. Causes Muscle Cramps

Drinking too much of water can cause muscle cramps

As mentioned before, consuming too much water will lead to a drop in your body’s electrolyte levels. The resulting fluid imbalance also affects your muscular function which could lead to muscle spasms and cramping. If you’re involved high endurance activities, it’s important to not only drink more water but also to replenish your electrolytes. Having a sports drink can help as most of them contain electrolytes

7. Chlorine In Water Increases Cancer Risk

Drinking chlorine water increases cancer risk

As much as we would’d to think that tap water is safe to drink, the fact remains that most drinking water in the United States has been treated with Chlorine to disinfect the water. Drinking too much of chlorinated water over a period of time means increased intake of chlorine. Studies have shown that the risk of bladder cancer increased with intake of tap water and beverages made with tap water.2

8. Could Lead To Hyponatremia

Drinking Too Much Water Could Lead To Hyponatremia

When there is excess water in the body, your body works harder to flush it out in order to maintain optimum water content. If you drink more water than your body can flush out, it impacts the amount of sodium, whose function is to balance the fluids in and around your cells. Drinking too much water causes hyponatremia or water intoxication, causing the fluid to move from your blood to inside your cells, making them swell. It can even lead to swelling in the brain which would require immediate treatment.

9. Can Affect Glomeruli

Too much of water can affect glomeruli

Glomeruli are a cluster of capillaries around the end of a kidney tubule. They form the first stage in the filtering process of the blood carried out by the nephron in the formation of urine. Overhydration can affect the glomeruli because your kidneys need to work overtime to filter the extra water from your blood.

10. Makes You Feel Tired

Too much of water can make you feel tired

Excretion of fluids is mainly the function of your kidneys. When you drink more water than is needed by your body, it’s your kidneys that are strained the most. They need to work hard to remove excess water which can lead to a stress reaction from your hormones. This could make you feel tired or fatigued.

How Much Water Should You Drink

Overhydration: Effects Of Drinking Too Much Water

After reading this list, if you’re wondering what the recommended daily intake of water should be, you may not find a perfect answer. Though most health care professionals recommend eight 8-ounce glasses, the general rule to follow is to listen to your body’s innate thirst mechanism. Other factors to consider are your lifestyle and food habits. Many foods also contain plenty of fluid which is absorbed by the body. This is why you may not feel so thirsty on certain days. Here are some factors that may impact your water intake.

  • Regular Exercise: If you exercise regularly or perform physical activity that makes you sweat excessively, you need to drink 1.5 to 2.5 cups more water than your usual intake.
  • High Intensity Exercise: Intense physical activities like marathons and triathlons demand a lot of energy from the body. Make sure you drink more water and also sports drinks with electrolytes.
  • Environmental factors: If the climate is hot and humid, your body will sweat more than usual resulting in water depletion. However, make you drink water in small quantities through the day.

Based on your lifestyle, figure out your approximate water intake and make sure that you’re always hydrated. If you’re not drinking enough water right now, it might take your body some time to adjust to the higher water intake and you might have to urinate more often. So give your body time and spread your water consumption through the day to avoid overhydration.

References   [ + ]

1. The water in you. The USGS Water Science School.
2. Cantor, Kenneth P., R. Hoover, P. Hartge, T. J. Mason, D. T. Silverman, R. Altman, D. F. Austin, M. A. Child, C. R. Key, and L. D. Marrett. “Bladder cancer, drinking water source, and tap water consumption: a case-control study.” Journal of the National Cancer Institute 79, no. 6 (1987): 1269-1279.