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Why does Water Taste Bad in the Morning?

You understand how I feel. You drank a glass of water the night before, crawled out of bed, and got up to start your day. You come across your glass of water on your desk and decide to take a small sip (you might have heard that drinking water first thing in the morning jumpstarts your metabolism and resets your digestive system). You recoil in horror. Why does your water taste so good… What is the term? Stale?

That is correct. According to scientists, water tastes stale after being left out for a night, and there are chemical reasons for the strange flavor.

Why does Water Tastes Bad in the Morning?

  • First, it is critical to understand that not all human oral physiology is the same. Only about half of the human population has what scientists consider a “normal” number of papillae, which are tiny bumps on your tongue studded with clusters of taste buds. The remaining half of the population is divided roughly evenly between so-called supertasters and non-tasters. The tongues of supers have more papillae than nons and a heightened sense of some tastes, whereas the tongues of nons have fewer papillae and a diminished intensity of taste.
  • Whether or not you find the relatively mild (to most people) taste of water palatable is partly determined by the number of buds doing the tasting in the first place. Bitter foods, such as raw vegetables, are frequently reported to be unpleasant by supertasters. For these people, trace particulates and minerals in water can elicit the same unpleasant bitter reaction.
  • The second factor contributing to a dislike of the taste of water is a little more bizarre. To put it simply, your mouth does not always taste the same. Assuming you went to work without eating, your mouth would eventually adjust to a mildly salty taste. You may not notice the taste gradually increasing inside your mouth, but as your body naturally dehydrates, your mouth takes on a salty quality.
  • When you take your first swig of water, your mouth’s factory settings are reset, but not always to the same location. Drinking water when your mouth’s salt receptors activate your bitter or sour taste buds instead. Similarly, drinking water after eating something acidic will activate your sweet receptors.

Other Factors Include:


The temperature of your water has a significant impact on its taste. You probably drank a small sip of refreshing water after pouring that glass of water from your cold Brita filter. What about the next morning? That water was most likely room temperature and didn’t taste as good.

Even though cold refreshing water tastes better, room temperature water aids digestion and helps maintain high energy levels. If you want to lose weight, drinking a glass of cold water has been shown to boost your metabolism and result in an extra caloric burn of 70 calories.

The point is that room temperature water does not taste as refreshing and crisp as cold water, which may result in a “stale” taste in your mouth in the morning.

Gases Dissolved

The gases that dissolve in your glass of water, however, are the true cause of that stale taste in your water. This is why, if you have a closed water bottle, you will not experience the same issue. Water’s solubility increases as the water temperature approach room temperature. Simply put, solubility is the ease with which gases dissolve in a liquid. Solubility increases with increasing temperature.

All of this means that various gases dissolve in your water over time. Carbon dioxide is one of these gases, as are aldehydes and acetone. The amount of carbon dioxide that dissolves increases your water’s acidity (or lowers the pH), which explains the strange new taste.

What Different Tastes Indicate?

Here are some of the flavors of tap water and their causes of them.

Fishy, earthy, soiled, moldy, and musty:

The most likely cause of any of these tastes is algal blooms in the source water, and as a result, this taste may be more noticeable in spring or other times when blooms are more likely, according to Heeger-Bernays. She says that municipal water is treated, so no algae should be present, but the taste may linger. Another cause of this flavor could be bacterial growth in the water system or even in a person’s sink, which is usually harmless.

Chlorine, bleach, chemical:

According to Heeger-Bernays, these flavors may be the most common in tap water. Because many systems use chlorine to disinfect their water supply, water may taste like chlorine. Smaller systems are more likely to use chlorine as a disinfectant because it is less expensive than other options, such as ozonation (the process of disinfecting water with ozone), she explained. Chlorine is present in treated water in small amounts and is safe to drink at these levels.

Medicinal, bitter:

According to the South Carolina Department of Health and Environmental Control, these tastes can be caused by copper in the water, usually caused by copper plumbing corrosion (SCDHEC). We can taste copper at 1.3 milligrams per liter; at that concentration, the metal can turn light hair greenish and be toxic to aquarium fish. On the other hand, copper only causes health problems above 60 mg/L, such as stomach cramps and intestinal discomfort.

This flavor can also be caused by a higher-than-normal level of total dissolved solids (TDS), which are minerals dissolved in water. If the TDS is mostly sulfates, such as Glauber’s salt (sodium sulfate) and Epsom salt, it will have a medicinal taste (magnesium sulfate). According to the SCDHEC, these can cause a temporary laxative effect in people new to drinking this water. Elevated zinc levels can also cause a medicinal taste. Zinc can cause nausea and vomiting at levels far above where people can taste the mineral. Wright stated that he has never heard of anyone becoming ill due to zinc in drinking water.


According to Southern Water, a company in West Sussex, England, animals falling into open water supplies may cause this taste, which is often more of a smell. According to the company, we should only address this issue if the odor persists. On the other hand, a gasoline odor may indicate dangerous contamination from nearby fuel sources.

The City of Milwaukee suggests determining whether the odor is coming from a single faucet or all of them. If there is only one, it is most likely a temporary issue, and even if it persists, it may be repaired by a plumber. However, if all faucets smell like gasoline, people should not drink the water, and we should notify the water supplier as soon as possible. According to the city, gas or fuel could be in the water.


Metallic tastes in water can be caused by zinc, iron, and manganese. Zinc is typically present due to corrosion of galvanized plumbing, whereas iron and manganese occur naturally in water sources. Iron and manganese in water can darken the color of tea and coffee and stain plumbing fixtures, appliances, and laundry. These minerals can also accumulate in water heaters, which we must drain regularly to prevent deposits. According to the SCDHEC, none of these elements should cause any health problems at the levels found in drinking water, even if we can taste them.


Chloride compounds are found naturally in water, dissolving as it travels through the earth. High chloride concentrations can cause a salty taste and accelerate corrosion of plumbing and appliances. The amount of sodium in water can also impact its flavor. Salt water may enter the drinking water supply in some areas. A sudden increase in the saltiness of water could indicate a leak from a saltwater system, according to Wright, and should be reported.

According to the SCDHEC, a sudden change in saltiness can indicate that sewage has gotten into the water supply because human and animal waste is high in sodium and chlorides. This is one of the tastes that can indicate a higher risk of illness. According to the SCDHEC, sodium in drinking water may be problematic for people on sodium-restricted diets.

Sulfur and rotten eggs:

Water that tastes or smells like rotten eggs can be caused by various bacteria or by hydrogen sulfide, which occurs naturally in water systems due to organic material decay. Although water authorities do not consider this a difficult issue, hydrogen sulfide can cause corrosion in plumbing, resulting in blackened water that may stain.

Wet dog:

According to Waterlogic, a water cooler and dispenser company, water that tastes or smells like a wet dog could be caused by metal plumbing, bacteria, treatment chemicals, or organic material in the source water. Water with this odor is probably safe to drink, but it should be tested for bacteria, according to the company.

Shavings from a pencil:

This is a one-of-a-kind water flavor with a difficult solution. According to England’s Southern Water, this taste is caused by antioxidants found in plastic pipes, and the only way to get rid of it is to replace the plumbing.

Why does Water Suddenly Taste Bad?

This is most likely the cause of a sudden increase in the taste or odor of chlorine in your water. Bacterial growth in wells If you get your water from a private well, there’s a chance that a type of bacteria called sulfate-reducing bacteria will grow inside.

How to Make Water Taste Better?

Add some fresh fruits.

Adding fresh fruits to your water makes it more enjoyable to drink. While citrus fruits like oranges, lemons, and limes are traditional water enhancers, you can also experiment with other fruit flavors that may appeal to your taste buds.

Slice or cube some fresh fruit and leave it in your water to add color and flavor. Berries, watermelon, mango, pineapple, orange, and kiwi are just a few colorful fruits that go well with a glass of cool, refreshing water.

Add a Squeeze of Juice.

Although we can use fruit juice to flavor water, tart juices like cranberry, grape, lemon, lime, apple, and pomegranate are particularly tasty.

Choose all-natural juices with no added sugars. Fruits and juices not only taste good, but they also contain vitamins and antioxidants that are good for your health.

You can make it even more interesting by serving it with complimentary fruit slices.

Make it Fizzy.

If plain water isn’t doing it for you, try sparkling or carbonated water. While enjoying a refreshing and bubbly beverage, you can reap some of the same health benefits as plain water.

Similarly to adding fruits and juice to water, you can add fruits and juice to sparkling or carbonated water.

Use Your Imagination with Ice.

Replace boring water with flavored ice cubes to add flavor, keep your drink cold, and get more nutrients from your daily water intake.

Chop your preferred additive, add it to an ice cube tray with water, and freeze. You could also try tea, juice, or coffee cubes. If you want to be more creative, use ice cube trays in fun shapes like hearts, stars, fish, or fruit.

Make a cup of tea.

Tea can also count toward your daily fluid intake. Tea is a great option that we can use in place of caffeinated beverages.

Herbal, green, fruit, red, and white teas are generally considered healthier than black tea or coffee because they contain little to no caffeine. You can also get these teas in a variety of flavors.

Attempt bouillons or broths.

If your palate leans toward the savory, skip the tea and sip one of those hot and savory liquids.

For maximum health benefits, choose low-sodium and low-fat varieties. Because soup is made of water, a cup of hot soup will help you meet your daily water requirements.

Utilize Herbs.

Another way to improve the flavor of water is to use herbs or leaves. Herbs are an excellent way to enhance the flavor of plain water. Fresh herbs, such as basil, lemongrass, lavender, or peppermint, can instantly add flavor to your water and taste like a mojito.

Steep the herbs in the water overnight, and add some lime or lemon juice in the morning to make it even better. To keep things interesting, experiment with different herb combinations.

Is Water Strange in the Morning?

You may have noticed that if you leave a glass of water on your bedside table overnight, it tastes strange in the morning. This effect, it turns out, is not all in your head; subtle chemical changes that occur overnight can change the composition of the water, making it slightly acidic.

What Factors Influence the Taste of Drinking Water?

The mineral content, as well as the fizzy sensation of carbonation and its high acidity, all have an impact on its taste. Many include additional flavorings or juice. Alkaline water contains naturally occurring, ionized minerals that raise its pH, making it less acidic and imparting a “smoother” taste.


Although it was a lot of chemistry (o-chem anyone? ), it’s nice to know why your water is stale finally. How do we solve this issue? Get a water bottle and place it in the refrigerator overnight. This way, you can wake up to cool water in the morning (hello, metabolism boost). If you prefer, cover your glass of water with a cap to reduce the amount of dissolved carbon dioxide in your glass of water.