Heat, Hydration and Health - drink up! - Life and Fitness Magazine

The Nutrition & Health Foundation has a multi-stakeholder approach to addressing the health challenges of our nation, by bringing together industry, government, state agencies, internationally recognised scientists, health professionals and other relevant stakeholders. It’s mission is to communicate evidence based information on nutrition, health and physical activity to encourage an improved and healthier society in Ireland.

Heat, Hydration and Health – drink up!

Whilst Ireland may not suffer temperature extremes experienced by other countries, typically July and August are the hottest months. Since we will be enjoying holidays and more outdoor activities, learn how to prevent overheating and dehydration for the family.

Importance of water in the body

Water plays an important role in health with an average total body water being 80% in children, 60% in adults and 50% in the elderly. We lose water when we breathe, sweat urinate or have a bowel movement to rid the body of waste products. Therefore, staying hydrated is extremely important in order to have the body function at its best, and to replace lost fluids.

Water and sweating

Hot weather increases the rate of sweating. This is the body’s way of keeping cool. Sufficient fluids are needed to allow this to happen. Dehydration occurs when the body doesn’t have enough fluid. When the weather is warmer or when playing sport, dehydration can happen sooner if fluid levels are not topped up.

Children can produce twice as much heat as adults for the same level of exertion. Unlike adults, they also tend to sweat very little which means they can over heat quickly. Hence, fluid intake is vitally important as a cooling mechanism.

Signs of dehydration

The body’s initial responses to dehydration are thirst (this can be a delayed reaction) to increase fluid intake along with decreased peeing to try to conserve water. The most sure-fire way of ensuring you are properly hydrated is by simply looking at pee colour – which will become concentrated and more yellow, the more dehydrated you are (ideally it should be light yellow in colour). As the level of water loss increases, further signs and symptoms develop; dry mouth, no longer able to make tears, irritability, stopped sweating, muscle cramps, nausea, vomiting and light-headedness. With further dehydration, more severe symptoms can occur. If concerned at any stage, seek medical help.

NHF Tips for hydration and cooling down

Drinking plenty of fluids, wearing sunscreen and hats, and avoiding strenuous exercise in the midday heat are the best ways to survive the heat and humidity.
Always wear light-coloured and loose-fitting clothing.
Whenever you get a chance, take a break in the shade.
Children, unlike adults, do not voluntarily drink enough in hot weather, and need to be reminded to take regular fluid breaks (even if not thirsty). It’s best to drink on a schedule.
Divide the amount of fluid you need for the day and drink it throughout the day rather than all at once. This is especially important if you engage in lots of heavy exercise and are a heavy sweater.
While pouring water over your head might feel good; it does not have any affect on your core body temperature – make sure you drink plenty of fluids to cool down.

Food and fluids hydrate!

All non-alcoholic fluids hydrate. That includes water, milk, juices and juice drinks, tea, coffee, still and sparkling soft drinks. Despite popular belief, caffeinated drinks can also count towards your fluid intake. Although the diuretic effect differs between individuals, even in those for whom caffeine has an effect, the impact is very small.

Tips for staying hydrated:

Ensure children have access to water at all times. Variety can be increased by adding sugar free squashes, well diluted fruit and vegetable juices, or sugar free flavoured waters.
Infants should be given only breast milk or formula milk unless your paediatrician or midwife tells you otherwise.
Including a drink with every meal and snack can help to remember to drink regularly throughout the day.
Sports drinks replace some of the salts you lose when sweating, they’re ideal for activities that last longer than an hour (for instance, hiking or biking treks) or even during very intense activities.
Foods provide fluid too – between 500ml-1L per day on average. Fruit, vegetables, salads, yogurts, soups etc all contribute to overall fluid intakes.
If thirst is a problem, it is worth discussing with your GP as some medications and chronic health conditions can increase thirst and might need further investigation.

The NHF recommends that when you and your family are out and about, remember to: