Fluids

Our bodies need fluids - and water is undoubtedly the best. When it is hot, when you are playing sport, or on any other occasions when you lose excessive fluid through perspiration, your requirement increases and you need to drink even more water or other fluids.

People who drink plenty of water gain many positive health benefits. Studies have shown that they have fewer kidney stones, are less likely to suffer from constipation, and are at lower risk for developing cancer of the colon or the urinary tract.

Water power

Involved in every function of your body, water controls body temperature; gives you energy; assists in weight control; helps transport nutrients and waste products in and out of cells; helps prevent you from becoming dehydrated after sweating; and is needed for all digestive, absorptive, circulatory, and excretory functions.

Children adapt less efficiently to hot weather than adults and are more vulnerable to heat. Their bodies produce more heat but they sweat less and therefore they take longer to change their body temperature. In addition, children's thirst mechanism is not as fully developed as that of adults and they may not express the need to drink. So they must be encouraged to drink water before, during, and after exercise to prevent the risk of dehydration and heatstroke.

What about soft drinks?

Because soft drinks are composed largely of water, sweetened fruit juice, cola, fizzy lemonade, and other popular drinks do provide the body with essential fluids. However, they also contain large amounts of sugar, which, when consumed in excess, causes tooth decay and leads to an unhealthy increase in weight. Sweet drinks can also cause a sudden increase in blood sugar levels.

In Europe, overweight and obesity in children is increasing, and the excessive consumption of soft drinks is believed to be a major contributory factor to this problem. The UK National Diet and Nutrition Survey revealed that consumption of fizzy drinks in the UK has doubled in the past 15 years. Young adults now drink an average of six cans a week.

Studies also show that children who consume a lot of calorie-laden soft drinks eat less at their regular meals, causing them to miss out on essential nutrients. By substituting healthier drinks such as semi-skimmed milk or water for carbonated drinks and squashes, nutritional deficiencies and obesity may be prevented in all age groups.

Caffeine and fluids

Coffee and tea are popular drinks, not least because of the stimulating effect of the caffeine content. While caffeine also acts as a mild diuretic and increases the amounts of fluid that the body loses in urine, this effect will not cause dehydration. So coffee and tea can count as part of your daily intake of fluids.

However, some people should limit their caffeine intake. In addition, caffeine can interact with certain medications: it may react with some antidepressants and diminishes the effect of some tranquillizers. High consumption of caffeine may also increase the excretion of calcium in urine and the risk of osteoporosis.

Lisa Hark, PhD RD & Dr Darwin Deen

Posted 30.06.2010

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