. Many families have the habit of drinking boiled water. In fact, drinking boiled water is good for the body, but you can’t drink it all at once after boiling. How long can’t you drink it? What harm does boiling water heat repeatedly? Let’s get to know it with you.
Five kinds of boiled water can not be drunk,
reboiled boiled water will cause excessive nitrite content in water. As we all know, excessive or excessive nitrite in water can cause fatigue, fatigue, drowsiness, coma, cyanosis, hypotension, abdominal pain, diarrhea, vomiting, and malignant diseases. The way to prevent boiling water pollution is very simple: firmly put an end to the reuse of boiling water, repeated boiling. In particular, the boiling water mentioned below should not be drunk.
1. After burning on the stove all night or for a long time, it is not cold or hot water when drinking;
2. Overnight boiled water in automatic water heater;
3. Residual boiling water after repeated boiling;
4. It is not the same day’s boiling water in the thermos;
5. Boiled water left after cooking.
boiling time of water
water must be boiled for 3 minutes before drinking, because drinking water that is not boiled thoroughly is easy to get cancer.
people in the city drink tap water. After ordinary river lake water is sent to the waterworks, it needs to be chlorinated to remove microorganisms and other impurities.
research shows that the content of halogenated hydrocarbon and chloroform is closely related to the change of water temperature and boiling duration. When the water temperature reached 90 ℃, the content of halohydrocarbon increased from 53 μ g / L to 191 μ g / L, and chloroform increased from 43.8 μ g / L to 177 μ g / L, both exceeding the national standard by two times. When the water temperature rises to 100 ℃, the contents of halogenated hydrocarbons and chloroform decrease to 110 μ g and 99 μ g respectively, still exceeding the national standard. If the boiling continues for 3 minutes, the content of halogenated hydrocarbon and chloroform will drop to 9.2 μ g and 8.3 μ g respectively, then it will become safe drinking water.
of course, boiling water is not as good as the longer it is burned, because the longer it is burned, there are no volatile harmful substances and nitrite in the water, which will be concentrated due to the evaporation of water, and the content will be relatively increased. Drinking such water is also harmful to the body.
How long can’t you drink after boiling water? Boiling water can kill bacteria and remove harmful substances. Because tap water is chlorinated, chlorine interacts with residual organic matter in water to form halogenated hydrocarbons Chloroform and other toxic carcinogenic compounds. When the water temperature reached 90 ℃, the content of halogenated hydrocarbon increased to 191 μ g / L and chloroform increased to 177 μ g / L, both exceeding the national standard by two times; When the water temperature just reached 100 ℃, the contents of halohydrocarbon and chloroform were 110 μ g and 99 μ g per liter respectively; If the boiling continued for 1-2 minutes, the contents of these two substances decreased rapidly to 9.2 μ g and 8.3 μ g per liter respectively, reaching the drinking standard. Therefore, boiling water for 1 ~ 2 minutes is the best.
in order to save water, some people often reheat the leftover boiled water, which is a bad habit. Because repeatedly boiling water will cause the loss of minerals beneficial to the human body, but also produce some harmful substances such as nitrite. Once a large amount of nitrite enters the human body, it can make the red blood cells in the blood lose the function of carrying oxygen, resulting in tissue hypoxia. People who drink this kind of water for a long time will have nausea, vomiting, headache, purple nails and lips, palpitation and other symptoms. In serious cases, it can also cause hypoxia, and may even induce cancer（ It should be noted that the content of nitrite in boiled water is lower than that in mineral water, but it is usually harmless.)
when drinking water, people will bring bacteria in mouth and saliva into cups and water, and they will grow and multiply in large quantities under appropriate temperature and environment. But don’t worry too much. In order to avoid the occurrence of the above situation, now qualified tap water and bottled water have a small amount of bactericidal substances – chloride. Kellogg Schwab, an environmental microbiologist at Johns Hopkins University in the United States, pointed out that the bactericidal effect of chlorides in drinking water can last for 1-2 days (if the water is put too long, don’t drink any more).
boiled water is not suitable for drinking after more than three days. If water is stored for a long time, it will be infected by bacteria and produce nitrite. Once a large amount of nitrite enters the human body, it can cause tissue hypoxia, nausea, vomiting, headache, palpitation and other symptoms. If it is serious, it can also cause hypoxia and death. Nitrite can also form nitrosamine in human body and promote the development of liver cancer and gastric cancer. When the boiling water in the thermos becomes warm, the bacteria will propagate faster and reduce more nitrite.
What’s the harm of repeated heating of boiled water?
in fact, it’s still harmful. Water is heated on the surface. In fact, part of nitrite in water existed as early as the first heating. Harmful substances always existed, and it would be toxic if heated again.
1. I drink pure water, distilled water and deionized water, which basically contains no impurities. No matter how I burn it, water is still water and will not become other substances. However, drinking water may contain trace amounts of harmful substances. Some of these harmful substances are volatile, which can be removed by boiling them repeatedly.
2, but some harmful substances will not volatilize, such as heavy metals, nitrates. The third reason that repeatedly boiling water can’t be drunk is that after repeatedly boiling water, the water evaporates and non-volatile harmful substances are left behind. In this way, the concentration of harmful substances increases, which is harmful to human body.
3. The water in the direct water dispenser is usually heated to 85 ℃. The water in the direct water dispenser is circulating (you pour out hot water and then pour in cold water to lower the total temperature). There is still some old water in the direct water. Distributor. This & lt; Old water & quot; It is hidden in the pathogen, which may lead to digestion and secretion. Urine and other diseases.
4. Re boiled water: some people are used to re boil the remaining warm water in the thermos bottle for the purpose of saving water, coal (gas) and time. But this & lt; Saving & quot; Not enough. Because the water burned and burned, so that the water evaporated again, nitrite will rise, often drink this water, nitrite will accumulate in the body, causing poisoning.
Benefits of drinking hot water. Drinking hot water can increase body temperature, open pores, discharge sweat, directly drive away body heat through perspiration, play a role in relieving summer heat.
drinking hot water in summer can accelerate the body’s blood circulation, promote water metabolism and accelerate the excretion of toxins. And through drinking hot water perspiration can also play a role in detoxification.
3 and Baowei
drinking too much at one time will make the stomach capacity expand rapidly, far beyond the transmission and absorption capacity of gastrointestinal tract, increase organ load and affect digestive function. Especially after the cow drink (fast, large amount of drinking), it is more harmful to carry out fierce activities again.
4, beauty and skin care
skin care is definitely inseparable from water, drinking more water can make the skin moist. It’s best to drink water 4-5 times a day. Don’t wait until you are thirsty. If your skin is short of water, it will appear dry and peeling. Boiled water can warm the internal organs, promote digestion, let the toxins stored in the body out of the body, make the skin more white and tender.
5, Runchang Tongbian
after getting up in the morning, the stomach and intestines have been emptied. At this time, drinking water can wash and clean the stomach, dilute the gastric acid, reduce the stimulation of the stomach, and keep the stomach and intestines in the best state. Drinking plenty of boiled water can stimulate gastrointestinal peristalsis, moisten intestinal tract, soften stool, promote the excretion of stool, and prevent constipation.