Drinking less water produces a series of changes in the body, most of which are unfavorable, ranging from mild thirst to severe cases that can lead to an increased risk of urinary stones, dehydration fever, and dry skin. Water is involved in the composition of cells in the body, so when too little water is consumed, it can lead to a lack of water in the body, which affects the functioning of the cells, and thus the body’s metabolism. Drinking too little water leads to blood concentration and an increase in the osmotic pressure in the body, leading to an increase in the secretion of antidiuretic hormone, which produces the symptoms of thirst and low urine output. Concentration of blood also leads to slower blood flow, increasing the risk of blood clots, urinary stones and other diseases. Drinking too little water can also lead to a decrease in body water which can lead to dry skin, and in extremely hot environments can lead to a rise in body temperature, i.e. heat stroke or dehydration fever. Therefore, you should ensure adequate intake of water, normal adults should ensure that the daily intake of 1500 ~ 1700 ml. But you need to be careful not to drink too much water, to prevent the heart caused by the burden.