We lose water through urination, respiration, and by sweating.
If you are very active, you lose more water than if you are sedentary.
Diuretics such as caffeine and alcohol cause us to lose water by tricking our bodies into thinking we have more water than we need.
Symptoms of mild dehydration include chronic pains in joints and muscles,lower back pain, headaches, and constipation.
A strong odour to your urine, along with a yellow or amber colour indicates that you are not getting enough water. (Note that riboflavin, a B Vitamin, will make your urine bright yellow.)
Thirst is an obvious sign of dehydration and in fact, you need water long before you feel thirsty.
Every day you lose water through sweating — noticeable and unnoticeable — exhaling, urinating and bowel movements. For your body to function properly, you need to replace this water by consuming beverages and foods that contain water. So how much water, or more precisely fluid, do you need?
This isn't an easy question to answer. A healthy adult's daily fluid intake can vary widely. Most people drink fluid to quench thirst, to supply perceived water needs and "out of habit." At least three approaches estimate total fluid (water) needs for healthy, sedentary adults living in a temperate climate.
Replacement approach. The average urine output for adults is 1.5 litres a day. You lose close to an additional litre of water a day through breathing, sweating and bowel movements. Food usually accounts for 20 percent of your fluid intake, so you if you consume 2 litres of water or other beverages a day (a little more than 8 cups), along with your normal diet, you can replace the lost fluids.
Eight 8-ounce glasses of water a day. Another approach to water intake is the "8 x 8 rule" — drink eight 8-ounce glasses of water a day (about 1.9 litres). The rule could also be stated, "drink eight 8-ounce glasses of fluid a day," as all fluids count toward the daily total. Though this approach isn't supported by scientific evidence, many people use this basic rule as a guideline for how much water and other fluids to drink
Dietary recommendations. The Institute of Medicine recommends that men consume 3 litres (about 13 cups) of total beverages a day and women consume 2.2 litres (about 9 cups) of total beverages a day. These guidelines are based on national food surveys that assessed people's average fluid intakes .
You can choose any of these fluid intake approaches to gauge your fluid needs. But your current total fluid intake is probably OK if you drink enough water to quench your thirst, produce a colourless or slightly yellow normal amount of urine, and feel well.
You may need to modify total fluid intake from these recommended amounts depending on several factors, including how active you are, the climate, your health status, and if you're pregnant or breast-feeding.
Exercise. If you exercise or engage in any activity that makes you sweat, you'll need to drink extra water to compensate for that fluid loss. Drink 2 cups of water two hours before a long endurance event, for example, a marathon or half-marathon. One to 2 cups of water is also adequate for shorter bouts of exercise. During the activity, replenish fluids at regular intervals, and continue drinking water or other fluids after you're finished. During intense exercise involving significant sweating, for example, during a marathon, sodium is lost in sweat, and you may need a sports drink with sodium rather than just water
Environment. You need to drink additional water in hot or humid weather to help lower your body temperature and to replace what you lose through sweating. You may also need extra water in cold weather if you sweat while wearing insulated clothing. Heated, indoor air can cause your skin to lose moisture, increasing your daily fluid requirements. And altitudes greater than 2,500 meters (8,200 feet) also can affect how much water your body needs. Higher altitudes may trigger increased urination and more rapid breathing, which uses up more of your fluid reserves. .
Illnesses or health conditions. Some signs and symptoms of illnesses such as fever, vomiting and diarrhoea, cause your body to lose extra fluids. To replace lost fluids, drink more water or oral re-hydration solutions (Gatorade, Powerade, CeraLyte, others). When water loss can't be replaced orally, intravenous water and electrolytes may be necessary. Increased water intake is nearly always advised in people with urinary tract stones. On the other hand, you may need to limit the amount of water you drink if you have certain conditions that impair excretion of water — such as heart failure and some types of kidney, liver, adrenal and thyroid diseases.
Pregnant or breast-feeding. Women who are pregnant or breast-feeding need additional water to stay hydrated and to replenish the fluids lost, especially when nursing. The Institute of Medicine recommends that pregnant women drink 2.3 litres (nearly 10 cups) of fluids a day and women who breast-feed consume 3.1 litres (about 13 cups) of fluids a day.
You don't need to sip from your water bottle all day to satisfy your fluid needs. Your diet, including the beverages you drink, can provide a large portion of what you need.
In an average adult diet, food provides about 20 percent of total water intake. The remaining 80 percent comes from beverages of all kinds.
Fruits and vegetables — besides being good sources of vitamins, minerals and fiber — contain lots of water.
For example, oranges are 87 percent water, and cucumbers are 95 percent water.
Milk, juice and other beverages also have large amounts of water. Conversely, dried fruits, nuts, grain products and baked goods generally contain less water.
Alcohol — such as beer and wine — and caffeinated beverages — such as coffee, tea or soda — can contribute to your total fluid intake.
But your best beverage is still water. Water is calorie-free, inexpensive when drawn from a faucet or fountain, and readily available in and out of your home.
Among the many benefits, water plays a major part in weight loss.
Since water contains no calories, it can serve as an appetite suppressant, and helps the body metabolise stored fat, it may possibly be one of the most significant factors in losing weight.
Water is the single most important nutrient you take in every day. It's fat free, cholesterol free, low in sodium, and completely without calories. Also, drinking more water helps to reduce water retention by stimulating your kidneys.
Dehydration leads to excess body fat, poor muscle tone & size, decreased digestive efficiency & organ function, increased toxicity, joint & muscle soreness, & water retention. Water works to keep muscles and skin toned