A person can go three minutes without oxygen, thirty days without food, but only three days without fluids (water), according to the golden rule. Nothing works in our body without water.
About 80 percent of a newborn’s body is made up of water. As we get older, the water content in the body decreases and is then around 60 percent.
Fat cells have a lower water content than other body cells. Similarly, overweight people have less water than thin people, and women have less water than men. For all of us, however, it is essential for survival to regularly supply our bodies with liquid through drinking.
Some organs contain excessive amounts of water. This includes our eyes, for example. Its vitreous consists of up to 99 percent water. At around 80 percent, muscles also have a high proportion of liquid. In order to supply our body with sufficient nutrients, we can do one thing above all: drink, drink and drink again.
Drinking water is an absolute must
Our body loses around two liters of fluid every day, firstly through the skin, which regulates the temperature in the body. This is especially true in the heat. But dry heating air can also affect us. The kidneys, which rid our body of toxins, excrete fluid in the form of urine. If we haven’t drunk enough, our urine is an intense yellow color. If it turns brown, this is a serious warning sign that something is wrong. The liquid is excreted with the stool via the intestines, and we also lose water in the form of tiny droplets when we breathe.
We have to compensate for these losses and therefore drink around 1.5 to two liters of liquid every day. The requirement increases during physical exertion, sports, high temperatures, fever, vomiting, and diarrhea. However, it doesn’t always have to be water. Soups, fruit, or various types of vegetables are also good for the body and help to replenish the stores.
This is absolutely necessary because our body already shows the first symptoms with a fluid loss of one to two percent. From a loss of about seven percent, we are on the danger side: an accelerated pulse or confusion indicates this because all chemical reactions and processes in the body require liquid. In the worst case, a deficiency of twelve percent can lead to a state of shock or even to a coma.
Our brain needs fluid to protect itself
Our brain and spinal cord cannot function without fluid either. We have about 140 milliliters of nerve or brain water, medically: Cerebrospinal fluid. It is a transparent liquid in which our brain floats in the skull and which protects it from shocks. Every day we form about half a liter of this liquid, which is also broken down again and of course has to be replaced accordingly.
The first signs that our body urgently needs water are headaches and dizziness, dry mucous membranes in the mouth and throat, and possibly difficulty swallowing. We’re tired, and we feel weak, but we don’t associate it with not drinking enough water.
In the heat and additional loss of fluids through sweating, it can happen that our circulation fails and we simply collapse. Our body tells us in no uncertain terms whether it is time to drink something because our blood pressure also rises. Without enough fluid, our blood thickens and can no longer easily keep the blood circulating.
The older you are, the less you feel thirsty
The older we get, the less we feel thirsty. It’s also not uncommon for older people to simply forget to drink enough. This can lead to dizziness, confusion, disturbances of consciousness, or loss of consciousness. If there is an extreme lack of fluids, doctors must infuse the body with appropriate amounts.
However, some older people consciously refrain from drinking enough, because in old age many can no longer control their urge to urinate as well as younger people. Fear of losing urine unintentionally or having to go to the toilet too often at night means that many drink too little or nothing at all.
When we need a lot of liquid
If we have diarrhea or vomit, our body needs more than the minimum of 1.5 liters a day. If the water balance is not restored as quickly as possible, the body dries out. A lot of fluids are also required when taking certain medications, for example, so-called diuretics. They have a diuretic effect and drain the body to prevent edema, i.e. water retention, for example.
Alcohol dehydrates the body
Alcohol also dehydrates our body because it has a diuretic effect. The kidneys try to flush the toxic substances out of the body, so we often have to go to the toilet to get rid of the urine.
Alcohol ensures that there is an inhibited release of so-called vasopressin in the hypothalamus. Vasopressin is a hormone that regulates water balance in the kidneys. However, if the body does not have a sufficient amount of this important hormone available, our kidneys excrete too much water. The water balance is disturbed, and everything gets mixed up.
Too much of a good thing can also be harmful
If we drink five liters or more within a few hours, this can also be life-threatening and result in so-called hyperhydration, i.e. overwatering of the body. The kidneys are then no longer able to regulate and excrete a large amount of liquid. One of the worst consequences can be cerebral edema.
Huge amounts of liquid are swallowed during the water-drinking competition. This can overwhelm the body. Not only can the kidneys not keep up with their work, but the salt balance is also destroyed. How and whether a body can cope with so much at all depends on age, weight, and general condition. The same applies here: the quantity makes the difference.