Water. It plays an important role in our world, and not just because it covers roughly 71% of the earth’s surface. The bodies of all living creatures consist of a certain amount of water.
Human Body
In some organisms, up to 90% of body weight is from water. In adult humans, it’s in the 55%-60% range. Water has several essential functions in our body. It regulates our internal temperature by sweating and respiration. It acts as a building material for cells. It metabolizes and transports in the bloodstream the carbohydrates and proteins our body uses as food. It forms saliva in the mouth, lubricates joints, and flushes waste from the body through urination. And it protects the brain, spinal cord, and fetus, by acting as a shock absorber. Without water, the human body wouldn’t work.
Did You Know…
- According to USGS.gov in 2019, water makes up 83% of your blood and kidneys, 79% of your heart, 75% of your brain and muscles, and 22% of your bones.
- Lean tissue holds more water than fat tissue. Since there is more fat in adult women, women’s bodies are made of less water (55%) than men’s (60%). And adult bodies, in general, have less water than babies (78% when born) and children (65% one year plus).
Hydration
With so much of your body made up of water, it’s not surprising that hydration is crucial. But don’t make the mistake of thinking getting hydrated only comes from drinking water. Look at the full picture, including other types of fluids you drink and foods you eat. In fact, most of your water intake should come from food.
Did You Know…
- Drinking water is an easy way to stay hydrated, but water intact also comes from drinking other liquids (herbal teas, fruit juices, broth, etc.) and eating water-rich fruits and vegetables.
- If you eat water-rich fruits, berries, and vegetables, you may not need as much water as when you eat dry or salty foods, like chips, grains, and bread products.
- Some studies suggest being hydrated may help with cognition. According to the American Society of Nutrition, well-hydrated children tend to perform better than dehydrated children, specifically in memory exercises.
- Many schizophrenic patients compulsively drink water because they hear “voices” telling them to drink and doing so quiets the voices.
- Being well-hydrated makes veins easier to find when having blood drawn.
- Data suggests people with a history of kidney stones and/or bladder infections can reduce their risk by drinking about two liters of water daily.
- The advice to drink eight glasses of water a day is a myth. It likely started in the 1940s when the U.S. Food and Nutrition Board suggested people should take in 84.5 ounces of water per day. What people missed was the clarification that most of this water would come from water-rich foods, not drinking water.
- Drinking when you get thirsty will usually provide you with enough water to function and thrive.
Dehydration
Dehydration is one of the most common and most preventable medical conditions. It can develop quickly, especially in the heat. It affects people of all ages, but the elderly are at a higher risk.
Humans can survive without water, but only for a short time. How long depends on a variety of factors (age, activity level, overall health, height, weight, sex, environment, food eaten, etc.), but the general rule of thumb is three days.
Did You Know…
- According to some studies, 75% of Americans are chronically dehydrated.
- Some of the signs of dehydration include feeling thirsty, having a dry mouth, lips, and eyes; dizziness or lightheadedness; fatigue; infrequently passing small amounts of urine; vomiting; and headaches.
- Signs of severe dehydration include high blood pressure; fever; hyponatremia; joint pain and muscle damage; and kidney stones.
- Dehydration can complicate other medical problems, as well as cause organ failure and death.
Drinking Water
Each person is unique. How much “extra” water you need to drink to stay hydrated depends on body weight (bigger people need more water), food eaten (water-rich foods increase water intake), environmental temperature (the hotter it is, the more water lost sweating), and physical activity (exercise means more sweating, too).
Bottom line? Without water, you die. But rather than a “one size fits all” approach, use common sense when it comes to how much water you should drink to keep your body hydrated.
Summer is here and it’s HOT! Heat-related illnesses are a real possibility if you aren’t careful. Click here for the CDC’s handout listing what to look for and what to do when it comes to heat-related illnesses.