Soft water: Water that contains no or less soluble calcium and magnesium compounds is called soft water. Natural soft water generally refers to rain, snow, rivers, rivers and lakes. Softening hard water refers to softened water obtained by reducing the contents of calcium and magnesium salts to1.0 ~ 50 mg/L. We usually refer to the content of calcium and magnesium ions in water as "hardness". The hardness of 1 degree is equivalent to 10 mg of calcium oxide per liter of water. Water below 8 degrees is called soft water, water above 17 degrees is called hard water, and water between 8- 17 degrees is called moderately hard water.
To know whether it is better to drink hard water or soft water, we must first understand the relationship between calcium and magnesium ions and human health.
Drinking water rich in calcium ions and magnesium ions in moderation is beneficial to health. Magnesium ion is helpful to activation in human body, and it also has the function of stabilizing neuromuscular conduction. Therefore, when the concentration of magnesium ions in the body is too low due to insufficient intake of magnesium ions, arrhythmia and abnormal vasoconstriction are prone to occur.
Normal people must take at least 350 mg of magnesium ions from food or drinking water every day to stay healthy. Because magnesium ions absorbed from food are easy to combine with cellulose in food, but not easily absorbed by human body, the most effective way to increase the absorption of magnesium ions in the body is to take them from drinking water.
Calcium and magnesium ions are essential nutrients for human body every day. If the water has a certain hardness, you can supplement a certain amount of calcium and magnesium ions by drinking water. If you take soft water for a long time, you need to supplement it through other channels. But the hardness of water is too high or too low, because the hardness of water is closely related to some diseases. In areas with high water hardness, the incidence of cardiovascular diseases is low, but the incidence in kidney calculi increases with the increase of water hardness.
China is mostly soft water in the south and hard water in the north. The standard of drinking water in China is that it cannot exceed 25 degrees, and the most suitable hardness of drinking water is 8- 18 degrees, which belongs to mild or moderate hard water.
The hardness of water is also related to taste. Hard water is refreshing, and most mineral water has high hardness, which makes people feel fresh and delicious, while soft water is tasteless.
But making tea and coffee with hard water will affect the taste. Some food processing water is special. Hard water will affect food processing, and it is easy to cause protein precipitation, inorganic salt precipitation or difficult cooking. Soft water is more suitable for beverages.
Boiler water should generally soften hard water, otherwise too much scale will cause accidents.