Water is an essential nutrient that is indispensable for human beings. Recently, water has been pushed to the forefront again, some people say “a thousand rolled water causes cancer! “Overnight water is toxic and should not be drunk” and so on, causing panic and questions.
So, these claims have a basis? How to drink water more safe and healthy? Today we will talk to you in detail!
Is thousand-rolled water really carcinogenic?
Thousands of boiled water, that is, water that has been boiled for a long time (repeatedly boiled). It is rumored that drinking such water can cause cancer, based on the “nitrate and nitrite” substances contained in it. In fact, water in the process of repeated boiling, due to the lack of oxygen at high temperatures, indeed, will lead to the conversion of some nitrate substances in the water into nitrite.
But containing it means it will cause cancer?
After experimental measurement, the content of nitrite in tap water is 0.007 mg / l, after boiling once the value of 0.021 mg / l, continue to boil 20 times after the content of 0.038 mg / l. And the content of nitrite in drinking water is 0.038 mg / l. The content of nitrite in drinking water is a clear “national standard” limit, the value is ≤ 1 mg / l; in other words, to reach the limit, theoretically need to boil the water 200 times.
Therefore, even after boiling for many times, the value is still far below the national standard, and cannot be generalized, in fact, there is no connection between thousands of boiled water and cancer.
Is overnight water really toxic?
Some people say that overnight water is toxic and even carcinogenic after drinking. The reason is still the problem of “nitrite”, nitrosamines are indeed a new type of drinking water disinfection by-products, but the amount of nitrosamines we consume from drinking water is “minimal”.
Because nitrosamines need a suitable environment and precursor substances, but the water after boiling in which the bacterial substances will lose activity, nitrate content is less, there is no basis for the production of a large number of nitrosamines.
Therefore, even if the water is boiled overnight, it does not change the nature of the water itself, the microbial content may increase, but will not produce greater harm to humans.
How to drink water more safe and healthy?
1, as long as the water you drink is clean, qualified and safe, can be safe to drink.
2, drink water, do not stick to “8 glasses of water”, cup size is different, the amount of water is naturally different.
The “Dietary Guidelines for Chinese Residents” recommends that adults drink 1500-1700ml of water per day is the most reliable, please calculate your own “cup” based on the size of the cup; in addition, if the weather is hot or some special people (outdoor workers, athletes, etc.), should also be appropriate to increase the amount of water.
3, hygiene, do not drink “raw water”.
Drinking water, pay attention to hygiene, to ensure clean and safe; many people are accustomed to drinking tap water without heating and boiling, but such “raw water” may contain chlorine, bacteria, insect eggs and other harmful substances. So, please heat and boil before drinking.
4, do not drink hot water and ice water, water temperature to “appropriate”.
Drinking ice water will make the gastric mucosa suddenly cold, causing capillary constriction, which will cause gastrointestinal discomfort; drinking hot water will undoubtedly damage the mucosa (esophagus, stomach), and even increase the risk of digestive tract cancer.
Therefore, about 37 degrees Celsius water is the most reliable, and body temperature, the human body will accept a higher degree.
5, drink slowly, do not “drink a lot of water at once”.
Do not rush to drink water, to “drink slowly in small bites”, refuse to drink a lot of water at once when thirsty, a single drink should not exceed 500 ml, refuse to “water poisoning”. Small sips of water, about 200ml each time, slow down the speed of drinking slowly.
6, do not wait until after thirst before drinking water.
For various reasons, many people always like to wait until after the thirst to drink water, but at this time the body has been seriously dehydrated, there is a greater threat to the body metabolism.
Therefore, develop a reliable drinking habits, wake up, before eating, before going to bed and other important time periods to deliberately drink a small amount of water.
7, a reasonable view of advertising, do not be obsessed with the “concept of water”.
The market “gimmick water” a variety of different, oxygen-enriched water, alkaline water and ecological water and other concepts of water; in fact, more are just “publicity gimmicks” only. In contrast, or plain water is more affordable and reliable, “concept water” and there is no magic, do not spend money for the so-called health.
