Water makes up two thirds of our body. It is vital we drink enough fluid to maintain a healthy balance. Many people get dehydrated by not drinking enough fluid or by losing fluids and not replacing them.
Good hydration prevents
- urinary tract infections (UTIs)
- dizziness that can lead to falls
- kidney stones
- pressure ulcers/skin conditions
- poor health
Good hydration is important for all age groups and is something for everyone to consider.
Who is at risk of dehydration?
Anyone can become dehydrated, but some groups are particularly at risk. These include:
- babies and infants – they have a low body weight and are sensitive to even small amounts of fluid loss
- older people – they may be less aware that they are becoming dehydrated and need to keep drinking fluids
- people with a long-term health condition – such as diabetes or alcoholism
- athletes – they can lose a large amount of body fluid through sweat when exercising for long periods
What are the signs and symptoms of dehydration?
Signs of dehydration are visible in your urine. Dark and strong smelling urine is a clear sign that you need to drink more fluids.
Use the above urine color chart to check for signs of dehydration.
Healthy urine is 1-3
Must hydrate is 4-8
Other symptoms of dehydration include –
- pain when urinating (UTIs)
- dry mouth, lips or eyes
- lack of concentration
If dehydration is left untreated, it can become severe. Severe dehydration is a medical emergency and requires immediate medical attention. Symptoms of severe dehydration include –
- feeling unusually tired (lethargic) or confused
- not passing urine for eight hours
- a weak pulse
- a rapid pulse
- fits (seizures)
- a low level of consciousness
If severe dehydration is not treated immediately it can lead to complications such as secondary UTI symptoms (e.g. E. coli bloodstream infections similar to sepsis) and falls due to dizziness. Severe dehydration can be life threatening, particularly for older people.
How can you stay hydrated?
If you’re active, or if the weather is particularly hot, there’s a greater risk that you will become dehydrated. To stay hydrated, you should increase your fluid intake.
If you, your child or someone you are caring for is ill, particularly with a fever, vomiting or diarrhea, there’s a high risk of becoming dehydrated, so it’s important to start replacing fluid as soon as possible.
If you are finding it difficult to keep water down because you’re vomiting, try drinking small amounts at a time to stay hydrated.
If you work in a care setting, plan visits around meal times to get a sense of what the person is drinking. Ensure the person has access to water or fluids and advise them of the recommended daily intake.
Remember you can always use the urine color chart to monitor your hydration levels.
By the British Health Service
Water: How much should you drink every day?
Water is essential to good health, yet needs vary by individual. These guidelines can help ensure you drink enough fluids.
How much water should you drink each day? It’s a simple question with no easy answer.
Studies have produced varying recommendations over the years. But your individual water needs depend on many factors, including your health, how active you are and where you live.
No single formula fits everyone. But knowing more about your body’s need for fluids will help you estimate how much water to drink each day.
Health benefits of water
Water is your body’s principal chemical component and makes up about 60 percent of your body weight. Your body depends on water to survive.
Every cell, tissue and organ in your body needs water to work properly. For example, water:
- Gets rid of wastes through urination, perspiration and bowel movements
- Keeps your temperature normal
- Lubricates and cushions joints
- Protects sensitive tissues
Lack of water can lead to dehydration — a condition that occurs when you don’t have enough water in your body to carry out normal functions. Even mild dehydration can drain your energy and make you tired.
How much water do you need?
Every day you lose water through your breath, perspiration, urine and bowel movements. For your body to function properly, you must replenish its water supply by consuming beverages and foods that contain water.
So how much fluid does the average, healthy adult living in a temperate climate need? The National Academies of Sciences, Engineering, and Medicine determined that an adequate daily fluid intake is:
- About 15.5 cups (3.7 liters) of fluids for men per day
- About 11.5 cups (2.7 liters) of fluids a day for women per day
These recommendations cover fluids from water, other beverages and food. About 20 percent of daily fluid intake usually comes from food and the rest from drinks.
What about the advice to drink 8 glasses a day?
You’ve probably heard the advice, “Drink eight 8-ounce glasses of water a day.” That’s easy to remember, and it’s a reasonable goal.
Most healthy people can stay hydrated by drinking water and other fluids whenever they feel thirsty. For some people, fewer than eight glasses a day might be enough. But other people might need more.
Factors that influence water needs
You might need to modify your total fluid intake based on several factors:
- If you do any activity that makes you sweat, you need to drink extra water to cover the fluid loss. It’s important to drink water before, during and after a workout. If exercise is intense and lasts more than an hour, a sports drink can replace minerals in your blood (electrolytes) lost through sweat.
- Hot or humid weather can make you sweat and requires additional fluid intake. Dehydration also can occur at high altitudes.
- Overall health. Your body loses fluids when you have a fever, vomiting or diarrhea. Drink more water or follow a doctor’s recommendation to drink oral rehydration solutions. Other conditions that might require increased fluid intake include bladder infections and urinary tract stones.
- Pregnancy or breast-feeding. Women who are pregnant or breast-feeding need additional fluids to stay hydrated. The Office on Women’s Health recommends that pregnant women drink about 10 cups (2.4 liters) of fluids daily and women who breast-feed consume about 13 cups (3.1 liters) of fluids a day.
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Beyond the tap: Other sources of water
You don’t need to rely only on what you drink to meet your fluid needs. What you eat also provides a significant portion. For example, many fruits and vegetables, such as watermelon and spinach, are almost 100 percent water by weight.
In addition, beverages such as milk, juice and herbal teas are composed mostly of water. Even caffeinated drinks — such as coffee and soda — can contribute to your daily water intake. But water is your best bet because it’s calorie-free, inexpensive and readily available.
Sports drinks should be used only when you’re exercising intensely for more than an hour. These drinks help replace electrolytes lost through perspiration and sugar needed for energy during longer bouts of exercise.
Energy drinks are different from sports drinks. Energy drinks generally aren’t formulated to replace electrolytes. Energy drinks also usually contain large amounts of caffeine or other stimulants, sugar, and other additives.
Staying safely hydrated
Your fluid intake is probably adequate if:
- You rarely feel thirsty
- Your urine is colorless or light yellow
A doctor or registered dietitian can help you determine the amount of water that’s right for you every day.
To prevent dehydration and make sure your body has the fluids it needs, make water your beverage of choice. It’s also a good idea to:
- Drink a glass of water or other calorie-free or low-calorie beverage with each meal and between each meal.
- Drink water before, during and after exercise.
- Drink water if you’re feeling hungry. Thirst is often confused with hunger.
Although uncommon, it’s possible to drink too much water. When your kidneys can’t excrete the excess water, the sodium content of your blood is diluted (hyponatremia) — which can be life-threatening.
Athletes — especially if they participate in long or intense workouts or endurance events — are at higher risk of hyponatremia. In general, though, drinking too much water is rare in healthy adults who eat an average American diet. By Mayo Clinic Staff