Watering your children

Fluid is often the forgotten nutrient. Dietitians and nutritionists frequently talk about the best foods for children to eat for growth, development and good health. But what are the best fluids? How much do children need? How do we know if they’re getting enough? By Kylie Andrew, Dietitian at the McKinnon & Albert Park Sports Medicine Centre.

Fluid requirements for children

Fluid is important right from the word go. The human body consists mostly of water, which is necessary for almost all bodily processes and functions right throughout the life cycle.

Water is lost on a daily basis, through breath, sweat and elimination. This water needs to be replaced daily. Although we get some fluid from food, we also need to drink a certain amount each day.

How much should children drink?

Children should drink 1.5 – 2 litres of fluid daily. This can include milk on breakfast cereal, milk smoothies and soups as well as water and other drinks. A lack of fluid results in dehydration, the effects of which can be quite severe.

Signs of dehydration:

• Thirst
• Tiredness and lethargy
• Headache
• Infrequent urination
• Dark coloured urine
• Fatigue
• Muscle cramping

What should children drink?

So what are the best fluids for children? Obviously water is one of the best choices, however there are other fluids that have plenty to offer:

Water – has the advantage of being cheap and readily accessible. It provides no extra kilojoules, which can be a problem for those with weight concerns. It does a good job at hydrating but offers no extra vitamins.

Milk – consumption needs to be more actively encouraged, as our children are not drinking enough. The National Nutrition Survey found that the number of children drinking milk daily reduces with age. The day before the survey, 90% of two to three-year-old children drank milk, but only 78% of eight to ten-year-olds did.

Given that these surveys also reveal that our children are not consuming enough calcium, this is real cause for concern. In addition to being an excellent source of calcium, milk is also a good source of protein and provides many other essential vitamins and minerals.

There exists a great deal of confusion as to whether we should be giving full cream or reduced fat milk to children. Children under  five- years-of-age should be given full fat dairy products, as they require the more concentrated energy source that fat provides.

Fat restriction can result in inadequate energy intake and impairment of growth. However, a supplement to the Medical Journal of Australia, states that children of normal weight aged over 5 years can be offered reduced-fat dairy products.

Soft drinks and cordials – provide a lot of sugar and no other important nutrients. These drinks should be used only occasionally, or not at all.

Sports drinks – play a role in helping children to rehydrate more effectively during and after vigorous physical activity. The carbohydrate in sports drinks replenishes fuel stores after exercise, whilst the electrolytes such as sodium help the body to fully rehydrate. Studies have also found that children drink more when offered a flavoured drink like a sports drink instead of water. However, sports drinks were not designed to be consumed as a soft drink.

Recommendations

A supplement to the Medical Journal of Australia, Recommendations for Nutrition and Physical Activity for Australian Children, recommends the following for primary school age children regarding fluid:

• Water should be encouraged as the preferred drink, with soft drinks and fruit juices used occasionally. During periods of vigorous physical activity children may rehydrate more effectively with the use of an electrolyte-replacement drink.
• Children of normal weight over the age of five years can be offered reduced-fat dairy products. However, these children should still obtain approximately 35% of their energy intake from fat, including mostly unsaturated fats found in nuts, seeds, olives and their oils, monounsaturated and polyunsaturated margarines, and some fish.

Fluid requirements for active children

Children who exercise in the heat should pay particular attention to their fluid needs to prevent heat stress. Children produce more heat per kilogram of body weight than adults, but are less able to transfer it to the skin. This results in less sweat – the body’s cooling mechanism.

Sports Medicine Australia recommends that active children drink 150-200ml (approx. 1 glass) of fluid 45 minutes prior to exercise, plus an additional 75-100ml every 20 minutes during exercise. After exercise, a liberal amount of fluid should be consumed as soon as possible.

Tips to encourage increased fluid intake

• Keep plenty of fluids cool in the refrigerator.
• Flavour water with a few slices of lemon and lime.
• Remind children to drink.
• Encourage children to drink even when they are not thirsty.
• Pack a drink bottle in your child’s school bag.
• Keep a drink bottle handy when they are playing sport.
• Encourage regular drink breaks from sport or play.
• Provide fluid sat all meal and snack times.

By Kylie Andrew

The information provided in this article is intended as a guide only. Always consult your doctor if you or your child is suffering any medical complaint. Any websites referred to by Australian Family contain information moderated by government and medical institutions or organisations.

This article was first published in Australian Family Magazine, May 2001. Updated July 2009.