The human body is anywhere from 55% to 78% water depending on body size. A rule of thumb, 2/3 of body is consists of water, and it is the main component of human body. Did you know that your tissues and organs are mainly made up of water? Here is the %:
Muscle consists of 75% water
Brain consists of 90% of water
Bone consists of 22% of water
Blood consists of 83% water
The functions of water in human body are vital. The water:
Transports nutrients and oxygen into cells
Moisturizes the air in lungs
Helps with metabolism
Protects our vital organ
Helps our organs to absorb nutrients better
Regulates body temperature
Detoxifies
Protects and moisturizes our joints
Every cell in your body needs water from head to toe. That is why it is so important to drink enough fluid. Take for example, brain consists of 90% of water, if you do not supply enough water to your body, your brain cannot function well, and you will get headache or migraine. Hence, next time, if you feel fatigue and headache, it may be the sign of dehydration.
Blood, muscles, lungs, and brain all contain water. You need water to regulate body temperature and to provide the means for nutrients to travel to your organs and tissues. It also helps transport oxygen to your cells, removes waste, and protects your joints and organs. Taking in too litter water or losing too much water leads to dehydration. Symptoms of mild dehydration include thirst, pains in joints and muscles, lower back pain, headaches and constipation.
A strong odor to your urine, along with a yellow or amber color, may indicate that you may not be getting enough water. Note that riboflavin, a B vitamin, will make your urine bright yellow when you take dietary supplements that contain large amounts of riboflavin. Certain medications can change the color of urine as well.
You lose water through urination, respiration, and by sweating, and you lose more water when you're active than when you're sedentary. Diuretics, such as caffeine pills, certain medications and alcohol may increase the amount of water your body loses. Lost fluids must be replaced by the fluids in the foods you eat and the beverages you drink.
How much water do you need to drink? At least twenty percent of the water you need comes from the foods you eat. The rest comes from the beverages you drink. Some experts believe you can estimate the amount of water you need by taking your weight in pounds and dividing that number in half. That gives you the number of ounces you may want to drink each day. For example, if you weigh 160 pounds, you might want to drink at least 80 ounces of water or other fluids per day. Other factors include amount of physical activity and the climate where you are located. My water calculator can help you determine how much water you need to drink each day.
Water is probably the best choice for rehydration because it's cheap and has no calories or added ingredients. Sweetened soft drinks and sodas have added sugar that adds extra calories but no additional nutritional value. Sports drinks contain minerals that may help keep your electrolytes in balance, which is good for recovering after a hard work out, but look out for added sugar and calories that you may not want. Fruit and vegetable juices can be a good choice because they have vitamins and minerals your body needs (read labels, however -- vegetable juices may be high in sodium). Caffeinated beverages like tea and coffee count too, but too much caffeine can make you feel jittery.