– By and large, everything that our body needs from water is H2O. Water is the basic medium for all biochemical reactions. We are essentially water and protein. These two components must continuously and regularly enter our body. If a person can live without food for several weeks, then without water, not more than one week.
Which water should we prefer? Tap water should be boiled. When water arrives at the station, it goes through all the necessary cleaning levels. But we do not know in what condition the pipes through which it passes. And there is a risk that during this way, undesirable substances, pathogens, can enter the water. Re-boiling water is when you boil it, allow it to cool below the boiling point, and then boil it again. Have you ever wondered what happens to water chemistry when you re-boil water? Is it still safe to drink?
What Happens When You Re-boil Water
If you have perfectly pure distilled deionized water, nothing will happen if you re-boil it. However, ordinary water contains dissolved gases and minerals. The chemistry of the water changes when you boil it because this drives off the volatile compounds and dissolved gases. There are many cases in which this is desirable. However, if you boil the water too long or re-boil it, you risk concentrating certain undesirable chemicals that may be in your water. Examples of chemicals that become more concentrated include nitrates, arsenic, and fluoride.
Does Re-boiled Water Cause Cancer?
According to Anne Marie Helmenstine, Ph.D. in biomedical sciences from the University of Tennessee, there is a concern that re-boiled water may lead a person to develop cancer. This concern is not unfounded. While the boiled water is fine, increasing the concentration of toxic substances may put you at risk for certain illnesses, including cancer. For example, excessive intake of nitrates has been linked to methemoglobinemia (a blood disorder) and certain types of cancer. Arsenic exposure may produce symptoms of arsenic toxicity, plus it has been associated with some forms of cancer. Even “healthy” minerals may become concentrated to dangerous levels. For example, excessive intake of calcium salt, commonly found in drinking water and mineral water, can lead to kidney stones, hardening of the arteries, arthritis, and gallstones.
The Bottom Line
Generally, boiling water, allowing it to cool and then re-boiling it does not present much of a health risk. For example, if you keep water in a teakettle, boil it and add water when the level gets low, you aren’t likely to endanger your health. It’s best if you don’t let water boil down, which concentrates minerals and contaminants and if you re-boil water, it’s better to do it once or twice, rather than make it your standard practice. Pregnant women and persons at risk for certain illnesses may wish to avoid re-boiling water rather than risk concentrating hazardous chemicals in the water.