Drink your way to perfect health.
Dehydration is common around the world but especially in hot, humid countries such as Dubai. "A lot of people don't even realise they are dehydrated, because they have become so used to feeling below their best," says Mariam M. Saleh, Clinical Dietitian, based at The American Hospital Dubai.
"Water is the largest single component of the body. Metabolically active cells of the muscles and viscera have the highest concentration, and calcified tissue cells (like bones) the lowest," says Saleh.
"As a percentage of body weight, water is around 50 per cent for adults. It varies among individuals depending on the proportion of muscle to adipose tissue (fat) Total body water is higher in athletes than in non-athletes and decreases significantly with age due to diminished muscle mass. Water has a direct role of maintaining body temperature besides the essential physiologic and metabolic functions," she says.
Harsh climate
"Water is needed for all functions, for example; digestion, blood circulation, transport, eliminating waste products. In a hot climate like Dubai, you will sweat more and lose more water," says Dr Denis Hardy, Paediatrician at the Manchester Clinic. "The obvious precautions are not to stay too long outside, especially in the middle of the day and to drink plenty of fluids."
Prolonged physical activity without consuming adequate water, especially in a hot and humid environment, can have a dangerous effect on your health.
"Hydration is important in relation to exercise because if you are not fully hydrated you can't work efficiently. If you are working really hard and not replacing water or a salt solution then your body stops running efficiently," says Sam Theyers, Personal Trainer.
Hot, humid weather increases the amount you sweat and the amount of fluid you lose. But you can also become dehydrated in winter if you don't replace lost fluids.
Teenagers who participate in sports may be especially susceptible, both because of their body weight, which is generally lower than that of adults, and because they may not be experienced enough to know the warning signs of dehydration.
Drinking water is not the only way to stay hydrated. "Some people do find water unpalatable but they can make it more interesting by adding slices of lemon and lime, or they can try diluting fruit juices. Fruit and herbal teas can be a good idea also. I recommend that we stay away from too many high sugars, fizzy drinks or lots of 100 percent fruit juice or smoothies as these could lead to an excess energy intake and weight gain," says Saleh.
"Tea and coffee and some soft drinks such as cola do contain caffeine, which is a mild diuretic, so in large amounts this could result in dehydration. However, if it was a weak tea or coffee it can count towards our fluid intake," she says.
Some people do not consume enough water, but they meet their needs with water contained in foods such as vegetables and fruits but should not count on that in hot weather conditions, says Saleh.
Water intake
Opinions are divided as to whether eight glasses of water a day is excessive. "Eight glasses of water is not excessive, there is no risk for healthy individuals to exceed their requirements of water, but a person should not intake an excessive amount of water. This could result in a condition called water intoxication, although this is quite rare," she says.
Anyone who exercises can become dehydrated, especially in hot, humid conditions or at high altitudes. But athletes who train for and participate in marathons, or take part in extended training sessions, are at particularly high risk. That's because the longer you exercise, the more difficult it is to stay hydrated.
During exercise, your body can absorb about 24 to 32 ounces of water an hour, but you may lose twice that amount in hot weather.
Dehydration is also cumulative over a period of days, which means you can become dehydrated with even a moderate exercise routine if you don't drink enough to replace what you lose on a daily basis.
"Hydration is not just about water," says Theyers. "Your body stores sodium and things like that so when you see marathon runners now you will often see them with a PowerAde or something similar. You have a lot of examples, you see a lot of elite sportsmen doing really well then all of a sudden they just collapse of exhaustion. Now this is not because they are dehydrated, it is because they haven't replaced the salt, just the water so your PH balance changes," he says.
"On average the body loses about 2.5 litres per day," says Dr Hardy.
"There is water in many foods — fruit and vegetables. You get water from lots of places. Caffeine can dehydrate you. For every can of sugary carbonated drinks, you should have two cans equivalent of water to replace that," says Theyers.
Rehydration
It is important to always drink plenty of water and not just when you are thirsty. "When you wake up in the morning you are slightly dehydrated as you tend to sweat through the night, so you should be drinking plenty of water then," says Theyers.
Your intake should depend on your size and the climate. Inadequate fluid intake combined with vigorous exercise and heavy perspiration can lead to heat injury, ranging in severity from mild heat cramps to heat exhaustion to potentially life-threatening heatstroke.
"The most common side effect from dehydration is muscle ache. You feel lethargic and you get really bad cramps. If your salt imbalance becomes very low it can result in massive cramps, fatigue and light-headedness," he says.
Dehydration prevents the body from transporting nutrients and oxygen to cells, regulating body temperature, cleansing the body of waste and toxins, metabolising stored fat, maintaining muscle tone and more.
Body exercise
"When you exercise your body slowly starts to cut down on the amount of blood that is sent to things, like the kidneys and the stomach, all the areas that are not used when you are running. Which is why if you eat a meal really close to exercising hard you can feel that the meal is just sitting there. This is because your body isn't doing anything about it. It needs to signal it's available to send oxygen and blood to the stomach, heart, arms and legs," says Theyers.
It is important to know the common signs of dehydration, in order to prevent any damage.
"There are many consequences with dehydration including feeling thirsty, weak, dizzy, tired, and getting a dry mouth, passing less urine, muscle weakness and headaches," says Dr Hardy.
"With severe dehydration there may be extreme thirst or loss of thirst. Adults become confused, there's a lack of sweating the blood pressure drops, the heart rate goes up. If there is fever untreated, there will be delirium, and a loss of consciousness. Babies maybe dehydrated if they have less than six wet nappies a day and older children and adolescents, if they go for more than eight hours without passing urine," he says.
