Tap water (mineral water, drinking)

Drinking water is the best thirst quencher of all and is a vital nutrient that has numerous functions in the human body. Drinking water as tap water can vary greatly in quality depending on your latitude location and region and whether you live in a municipal or rural area.

Culinary uses of drinking water:

Depending on where you live, you can drink water straight from the tap and use tap water to prepare food. The US drinking water supply is mostly safe to drink, as is tap water in Canada, the UK, Australia, and New Zealand. The more limestone (calcium and magnesium) that the water contains, the harder it will be.¹ While hardness does not diminish water’s quality, if water is particularly hard it will become slightly cloudy and its flavor will be impacted. You can use a water filter to reduce the amount of limestone that the water contains. Household appliances using softer water often have a longer life.

Water is an essential ingredient in soups and can be used to boil and steam a wide variety of food. Boiling food results in vitamins and minerals being transferred to the water. Cooking vegetables in salted water makes the cell walls of the vegetables more permeable because of osmosis. This reduces the amount of time that you need to cook the vegetables for and means that a greater proportion of the vitamins and minerals are retained. Legumes, on the other hand, should only be salted after cooking. If you cook legumes in salted water, the cooking time will be longer. If cooking your vegetables is important to you, you can keep the cooking water and use it for soups and sauces to ensure that the vitamins and minerals are not lost. Steaming, blanching, and sautéing are undoubtedly gentler cooking methods than boiling because more of the (heat-sensitive and water-soluble) vitamins and minerals are retained. But steaming and sautéing are the best methods for retaining nutrients because minimal cooking liquid is used.

Water is necessary to maintain all life processes in the body meaning that is essential to pay attention to whether you are drinking enough water. According to the Swiss association for nutrition (Schweizerische Gesellschaft für Ernährung, SGE), a person weighing 70 kg needs a total fluid intake (drinks plus food) of about 2–2.5 liters per day. However, this recommendation remains controversial because to date no strictly scientific studies have been conducted on human fluid intake.² It is important to bear in mind that the SGE is sponsored by major companies that produce drinks, namely, Nestlé and Coca-Cola. But drinking 2–3 liters of water is nonetheless advisable, and is also the recommendation of the World Health Organization (WHO).³

If you follow the recommended food pyramid, approximately 1 liter of the water that you will need in a day will come from the food you eat. Fruits and vegetables contain up to 95 % water, but fish and meat (65–70 %), bread (35 %), and other grains (12 %) also provide a lot of water. You should drink 1–2 additional liters of liquid per day.⁴

Tap water is the most effective liquid for quenching your thirst and is calorie-free. You can flavor water in a variety of ways, for example, you can use it to make herbal tea or a fruit tea, or you can add citrus peel, ginger, peppermint, basil, lemon balm, or fruits such as apples, raspberries, and strawberries.

According to the Swiss food pyramid, milk, fruit juice, and vegetable juice are not classified as beverages because their main purpose is to provide nutrients such as vitamins, minerals, and protein, and not to quench thirst. Caffeinated, alcoholic, and sweetened drinks are classified as indulgence foods. These should be consumed with particular restraint or avoided altogether.⁶

If you want to ensure that your tea is as delicious as possible, it is best to use soft water or filtered water. However, using mineral water to prepare tea is not advisable because of the high salt content that it contains.⁷

Vegan recipes with drinking water can be found under the header: “Recipes that contain the largest amounts of this ingredient” (at the very bottom or on the side of the screen).

Purchasing — where to shop?

Tap water is much cheaper than mineral water. In the US, one thousand gallons of water costs approximately $1.50.⁸ The price that you pay for tap water is higher than this because it includes service charges. Consuming tap water is better for the environment than bottled mineral water: filling, packaging, and transporting a bottle of mineral water consumes an average of one thousand times more energy than supplying the same amount of drinking water. The process emits one thousand times more CO₂.^9,10

Finding wild:

If you run out of drinking water on a hike, the Swiss television program Puls (SRF) gives the following advice: Tap water is generally available from wells in nearby villages. If it is a public well and the water is not suitable for drinking, it must be explicitly labeled “no drinking water.” However, if the well is located on a mountain, pasture, or private property, it does not have to specify whether or not it is drinkable and may not be suitable for human consumption. These wells may be designed for animals, and the water often comes from streams. If you drink from a stream, it won’t be life-threatening but may lead to vomiting and diarrhea. Small children, pregnant women, and elderly people are advised not to consume water from streams.11

Making your own sparkling water:

You can make “homemade” sparkling water using devices by brands like Sodastream. These devices work by forcing carbon dioxide stored in a cylinder into the water. However, they are susceptible to impurities and may contaminate the water.¹² If you have stomach problems, you should avoid carbonated water. See the section “Dangers — intolerances — side effects.”

Storing:

Unlike most foods, water doesn’t really have an expiration date. It cannot rot nor go moldy nor ferment. However, if water is stored open, its chemical composition changes. Water absorbs CO_², which produces a small amount of carbonic acid and slightly changes its flavor. If water is left out for more than one day, dirt particles and bacteria from the air settle on the water and may make it undrinkable.¹³

Mineral water retains its quality best when stored in a dark, dry, cool place. Storing water in a glass bottle will give it a shelf life of many years without affecting its flavor. Storing water in PET bottles will reduce its shelf life because of the lack of density of the bottle (the shelf life will be at least 1 year). Carbon dioxide may escape through the PET bottle. Furthermore, if PET bottles are not stored well, acetaldehyde can pass from the PET into the beverages. Although acetaldehyde is not considered to be harmful to one’s health, it may cause the water to have an unpleasant smell or flavor.¹⁴

Nutrients — nutritional information — calories:

Water is an inorganic compound of hydrogen and oxygen (H₂O). Tap water is fresh water and tends to be fairly pure. However, its quality and nutrients can vary greatly depending on the latitude, country, and region it comes from.

The following minerals are most frequently dissolved in drinking water: calcium (Ca²⁺), magnesium (Mg²⁺), and sodium (Na⁺), and the anions carbonate (CO₃^2-), hydrogen carbonate (HCO₃^-), chloride (Cl^-), and sulfate (SO₄^2-). Water hardness is the sum of the concentration of calcium and magnesium.⁹ The nutritional composition of the soil where the water comes from has a strong influence on the concentration of the respective nutrients.

Tap water contains much less calcium than mineral water. For example, water from Meggen, Switzerland, contains 41.3 mg/liter (i.e., 4.1 mg/100 mL) calcium and has a pH value of 7.93. This is 12 times less than mineral water on average. Across the US and Canada, the calcium concentration of water varies from 1 to 135 mg/L.¹⁵

Drinking water standards are legally regulated and vary from country to country. This protects consumers by setting upper limits on the amount of various nutrients and substances that the water may contain. Control of water quality therefore helps to prevent water from having any adverse effects on the population.

Select CLICK FOR under the photo of the ingredient to see the nutrient tables. These tables provide complete nutritional information, the percentage of the recommended allowance, and comparison values with other ingredients.

Health benefits — effects:

Water is essential to life. An adult body consists of about 60 % water. Water performs an array of functions in the body, for example, it acts as a solvent and transporter of nutrients, enzymes, and hormones. It ensures the excretion of toxins and waste, supplies the skin and tissue with moisture, and regulates body temperature and metabolism. Water furthermore supports digestion and will make your stool softer.

The body continuously excretes water and vapor through urine, stool, breathing, and sweating. This means that you need to continuously replenish your body’s supply of water by consuming food and drinks. See the above section on culinary uses. Certain conditions may mean that you need to consume greater amounts of fluid (e.g., hot weather, sport, physical work, consuming high quantities of salt, dry air, and illness).⁴

Mineral water is both a thirst quencher and a good source of calcium. In theory, you could meet the recommended daily intake of calcium by drinking two liters a day of certain mineral waters. However, you should check the calcium content of the specific mineral water you are drinking as it can vary from 1 mg/100 mL to more than 60 mg/100 mL. You can find a list of calcium-rich mineral waters in the article A Vegan Diet Can Be Unhealthy. Nutrition Mistakes. You should also check the magnesium content of the water that you drink because magnesium is necessary for both the transportation of calcium and its absorption. The ideal ratio between calcium and magnesium is about 2:1.¹⁶

In addition to mineral content, it is also important to consider the pH of tap water. This is because the body compensates for acid stress (proportionately low amounts of pH and high amounts of acid) by taking minerals such as calcium from the bones.¹⁷ If the pH value of water is below 7, you can increase it to approximately 7 pH by adding lemon juice to the water. Lemon juice has a very low pH value before digestion, but metabolism and the citrate cycle affect its pH levels. We metabolize organic acids and use them to produce energy. We exhale this energy as CO₂ once it has been used.¹⁸

The quality of tap water varies from region to region; however, it is generally safe to drink in the US, Canada, the UK, Australia, and New Zealand. Lack of treatment and monitoring of water may reduce the quality of the water: this may particularly be a problem in the US, Spain, Portugal, Italy, and Greece. The quality of drinking water may also vary from residence to residence. If the tenant or owner of the house is gone for a long time (e.g., traveling), the water may stagnate. However, this can be fixed by letting the water run for about one minute before drinking.¹¹ The quality standards imposed on tap water are higher than for bottled mineral water.⁹

Natural mineral water must be “originally pure,” but this is not a requirement of tap water, which may be treated and mixed. Water that has been mixed with carbon dioxide (i.e., opened) must be declared as tap water, regardless of the quality of the water and the minerals it contains. In Germany and Austria, “healing water” (Heilwasser), on the other hand, is categorized as a medicinal product.²⁰

Dangers — intolerances — side effects:

If you don’t drink enough or your body excretes more water than you are taking in, you will be dehydrated. If you lose 1–5 % of your body weight in water, you are likely to experience some of the following symptoms: thirst, malaise, loss of appetite, nausea, restlessness, and increased heart rate. Other signs of dehydration include headaches, a decrease in concentration and reaction time, and reduced physical performance. If you don’t consume enough water over a longer period of time, you may risk constipation. In the long term, not consuming enough fluids can have very serious consequences including palpitations, muscle cramps, and unconsciousness. Dehydration can ultimately lead to death.

On the other hand, if you drink too much, you may be putting your kidneys under strain, which is also dangerous. Marathon runners should compensate for their fluid loss not only through drinking water but also with sodium (e.g., table salt); otherwise, overhydration with a low sodium concentration in the blood serum (dilution hyponatremia) may occur if runners only drink water. In some rare cases, drinking too much water has ended fatally. One cannot drink “on reserve.”²

If you have stomach problems, you should avoid carbonated mineral water. Chemically speaking, carbonic acid is neutral, not acidic: carbonated mineral water has a pH value of 7. However, carbonic acid promotes the formation of gastric juice and acidic burping. This is why people with sensitive stomachs should stick to still water.²¹

In parts of the US, drinking water is often contaminated, for example, with lead. This can lead to skin rashes, nausea, and hair loss if consumed over a long period of time. Lead may furthermore cause malformations in pregnant women and small children. These contaminations are often the result of government austerity measures that rationalize away controls, renovations, and maintenance to water pipes and storage facilities.²² In the EU and the UK, lead pipes are banned for tap water in houses. Fittings, water meters, and pressure-reducing valves may contain small amounts of nickel and lead in the alloys; however, testing requirements have increased in recent years. If lead pipes are still present in older buildings, it is mandatory to inform consumers. If lead is present in a building, we advise pregnant women and children to switch to packaged water.

Tap water in the US tends to be very chlorinated. Chlorine and chlorine dioxide are commonly used to disinfect drinking water all over the world. Adding chlorine to water is mandatory in the US and many European countries. The effects that the ongoing consumption of chlorinated water can have on your health are controversial. Opinions range from viewing chlorinated water as harmless²⁴ to seeing it as alarming²⁵. In the US, the maximum amount of chlorine that water is allowed to contain is 4 mg chlorine per liter²⁶, but according to the WHO, water usually contains less than 1 mg/liter.²⁷

When tap water is treated with chlorine, chlorine dioxide, and ozone, the disinfection by-products chlorite and chlorate may form. The maximum quantities of these substances that are allowed to be present in water is also regulated; a maximum of 0.2 mg/kg of chlorite and chlorate should be present in drinking water.³⁰ The substances are said to have a harmful effect on health.

Overfertilization in agriculture (especially with liquid manure) or old sewage treatment plants can increase the amount of nitrate in the groundwater considerably. This can make the drinking water dangerous, especially for babies and small children. Treatment, building deeper wells, and good cooperation with the agricultural sector may be able to reduce the concentration of nitrate. Pollutants from sewage treatment plants and factories often end up in rivers, which is a danger for all living beings. In addition, drugs or other pharmacologically active substances (e.g., X-ray contrast agents, and sex hormones) can also contaminate drinking water.⁹

Water filters are not necessary in countries and regions where the water quality is high. There are nevertheless a wide range of water filters on the market to filter out nitrates, pesticides, and chlorinated hydrocarbons. These filter cartridges often contain ion exchangers or activated carbon. You should replace the cartridges regularly as their capacity becomes exhausted and the substances that they catch may pass back into the water. Filters are generally susceptible to germ formation. Table filters may be useful for softening water with high calcium contents. A high concentration of calcium may alter the flavor of the tea and coffee considerably. On the other hand, calcium and magnesium are lost through decalcification.¹⁴

General information:

Compared to other natural resources, with water we tend to talk about water use rather than water consumption. Wikipedia states that “in principle, the amount of water on earth remains the same in all aggregate states; it is merely the distribution of this water that changes. Only a very small amount of water vapor escapes through the atmosphere into space”.⁹ Water use can lead to contamination and pollution.

How water is treated: Chlorine is added to water to disinfect it. Waterworks add chlorine in the form of chlorine gas, chlorine dioxide, or sodium hypochlorite. Alternative methods for disinfecting swimming pools and tap water are ozonation and UV radiation. In most countries, extensive accident prevention regulations apply to adding chlorine to water.³¹

Author: Kerstin Gackle | 30 Sept 2016