So, how much water do people need to drink every day? Is it better to drink more water? Is it true that the legendary boiled water and overnight water cause cancer? Why do some people drink ice water every day, and some people have stomachaches when they drink it?
"Too long to watch" version:
1. The daily water consumption of healthy adult women should be 1.5L, and that of men should be1.7l..
2. Drinking too much or too fast can lead to water poisoning, which can be life-threatening in severe cases.
As long as the drinking water is up to standard, cold water and warm water are harmless to the body, but don't drink too hot water, which will damage the esophagus.
4. The nitrite content in boiled water and overnight water is safe, and it will not cause cancer if you drink it frequently.
Generally speaking, when water intake and water discharge are roughly equal, the body is in a state of water balance, that is, a state of normal hydration. If you take in too little water or lose too much, your body will be dehydrated. Too much or too fast intake of water may lead to water poisoning.
According to the recommendation in the Reference Intake of Dietary Nutrients for China Residents, the daily drinking water of healthy people should be the following values under the condition that the ambient temperature and humidity are suitable and there is no strenuous exercise.
But this is only a reference value, which does not mean that anyone can only drink this water every day under any circumstances. If you eat a lot of fruits, vegetables, porridge and other foods with high water content, you can drink less; If you sweat a lot or are pregnant and other special people, you need to drink more.
But drink more, not too much. Water poisoning means that the total intake of water exceeds the discharge, and some water stays in the body, often accompanied by abnormal electrolyte ratio and hyponatremia.
Among them, acute water poisoning has prominent mental and neurological symptoms, such as headache, blurred vision, disorientation, mental disorder, lethargy, muscle twitching, even convulsions, coma and even life-threatening; Chronic water poisoning progresses slowly, with fatigue, fatigue, lethargy, inattention and apathy, often accompanied by loss of appetite, nausea and vomiting, pale and moist skin, depressed edema, elevated blood pressure and increased pulse pressure difference.
The compensation mechanism in healthy people is perfect, and the probability of drinking water and eating normally and being poisoned by water is very small. However, patients with strenuous exercise or renal insufficiency need to limit drinking water.
Because after strenuous exercise, a lot of salt in the body will be lost because of sweating. Drinking a lot of water in the later period will not only accelerate the dilution of sodium content in blood, but also destroy the metabolic balance of water and salt in the body. Even if you drink sports drinks, it is easy to cause gastrointestinal discomfort.
I suggest that you don't drink water just after exercise, wait until your heartbeat calms down, and then drink water several times. If it is a high-intensity strenuous exercise with a lot of sweating above 1 hour, you can supplement sports drinks. When drinking, it should not exceed 100 ml each time, and the hydration interval is about 10 minute, so that the body will be replenished with water slowly and there will be no uncomfortable reaction.
However, in the oliguria and anuria stages of acute renal failure, there are obstacles in the dilution and concentration function of the kidney, and excessive intake of water will lead to the risk of water poisoning; In addition, in the oliguria stage of acute renal insufficiency, severe heart failure or cirrhosis, the renal drainage function drops sharply. If these patients do not control their drinking water, it may also be dangerous. Such patients need to drink water according to the doctor's advice.
Whether in traditional cognition or online teasing, it seems that drinking hot water can solve 99% of minor physical problems, while drinking ice water often can lead to diarrhea/indigestion/gastroenteritis. ......
This is because there was no disinfection and sewage system for tap water in ancient times. Microbial pollution of water sources is the most important reason for the prevalence of infectious diseases in the past. Boiled water can play a bactericidal role. Over time, we have formed the habit of drinking hot water and the taboo of cold water.
Therefore, whether after the flood or in the wild, don't drink raw water directly, because even if you use river water, mountain stream water, well water, spring water or lake water that looks clean to the naked eye, it may have been polluted by animal droppings, organic or toxic chemicals. And it may already contain germs or parasites, so it is very dangerous to drink it directly.
But in city life, it is good to look at one's drinking habits. You can drink hot water or ice water. As long as the drinking water meets the hygiene standards, it will not cause any harm to health.
The reason why some people have diarrhea when drinking ice water may be because they have lived in an environment of drinking warm water since childhood, and their gastrointestinal function is relatively weak, so they are sensitive to cold water stimulation, so they don't have to be forced to drink at any temperature.
However, don't drink too hot water. Boiling water must be kept for a while, and the temperature should be appropriate, so as not to burn your hands. Because high-temperature water enters the esophagus, it will destroy the esophageal mucosa and increase the risk of esophageal cancer over time.
On the issue of drinking water, we often hear another rumor: you can't drink water/boiled water overnight, which will produce a lot of nitrite and lead to cancer.
Although, in the process of repeated boiling of water, it does lead to some nitrate substances in water being converted into nitrite. However, the nitrite content in tap water is 0.007 mg/L, the value after boiling once is 0.02 1 mg/L, and the content after boiling 20 times is 0.038 mg/L.. However, the content of nitrite in drinking water limited by "national standard" is1mg/L. Therefore, if drinking water is heated several times repeatedly, there is no need to worry about cancer.
Overnight water is also safe, because most microorganisms have been killed after drinking water is boiled at high temperature, and the nitrate content is less, so there is no basis for producing a large amount of nitrosamines, so there is no cancer problem.
From this extension, the nitrite content of overnight meals is actually within the safe range, and eating leftovers will not cause cancer. However, it should be noted that leftovers will have the risk of microbial reproduction and food deterioration, which will lead to food poisoning. Therefore, it is best to eat on the same day and try to eat less overnight meals.
In short, when drinking water, you should pay attention to small intake many times. Don't wait for thirst and yellow urine before looking for water to drink, and you don't have to listen to the online "drinking water and detoxification schedule" because all organs of the body are "working" 24 hours a day and will not "detoxify" at a specific time.
References:
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