Hydration and Water

The average adult body requires approximately 2.5-3L per day.

When was the last time you had a drink?

Would you know the signs of dehydration?

Why is water important?

1. Maintain the health and integrity of every cell in the body
2. Keep the bloodstream liquid enough to flow through blood vessels
3. Help eliminate the byproducts from our metabolic functions
4. Regulates body temperature and allows muscle contractions to take place
5. Moistens mucous membranes in lungs and mouth
6. Lubricates and cushion joints
7. Reduces the risk of cystitis by keeping the bladder clear of bacteria
8. Aids digestion and prevents constipation
9. Moisturises the skin to maintain its texture and appearance
10. Carry nutrients and oxygen to cells
11. Serve as shock absorber inside the eyes, spinal cord and in the amniotic sac surrounding the fetus in pregnancy

Did you know…

• The total body water content is higher in males than females (therefore males need to drink more to replace losses.
• You can lose as much as 1.5L during a 3 hour airline flight.
• Most adults lose an average 2.5-3L per day and this amount will increase in hot weather and with increased exercise. If you are feeling thirsty you may already be dehydrated.

Signs of dehydration

• Dry mouth and throat (this usually is our first sign of thirst)
• Dark concentrated urine and infrequent urination (this can be a late sign)
• Dizziness or light headedness
• Muscle cramps
• Nausea/headaches
• Inability to concentrate

Recommended amounts – estimated

Adult women ~2 litres (eight cups) per day to prevent dehydration
Adult men ~2.6 litres (about 10 cups) per day to prevent dehydration

How can I replace my fluid losses?

• The body can get approximately 20% of its total water requirements from food
• Fresh water and other liquid drinks include milk, coffee, tea, soup, juice, soft drinks
• Fresh fruit, jelly

The best sources of fluid replacement generally include:

1. Fresh water, no calories (kilojoules)
2. Milk (particularly low fat versions) is an important fluid, as it is about 90% water.
3. Tea can help you meet your daily recommendations and is also a source of antioxidants, polyphenols which may help protect against heart disease and cancer
4. Have fresh fruit over fruit juice because it has more fibre, high level of nutrients, and less sugar

Try these helpful tips to get more fluid into your day

1. Add a squeeze of lemon, lime or mint leaves or berries into plain water for extra flavour
2. Add ice cubes made from fresh fruit to a glass of water
3. Take a bottle of water with you, have water at your desk and with you in your car so you are able to sip throughout the day
4. Have drinks of water with your meals and snacks

What about during exercise?

How much water?

During exercise:

Drinking fluid during exercise is necessary to replace fluids lost in sweat. Ensure adequate hydration during exercise helps reduce the risk of heat stress, reduce cramps through maintaining normal muscle function, and ensure optimal performance.

As dehydration increases, there is a gradual reduction in physical and mental performance. Studies have shown that a loss of fluid equal to 2% of your body mass is enough to decrease ones performance. During performance dehydration can impact in the following ways;

• Increase in heart rate
• Increase in body temperature
• Increased perception of how hard the exercise feels (especially if training in the heat)

Other causes of dehydration

Stress – when we’re feeling exhausted and under pressure, stress can disrupt the production of the hormone aldosterone. This hormone helps regulate your fluid and electrolyte levels, triggering dehydration

Herbal supplements – such as dandelion, parsley and celery seed increase urine production and are used to treat fluid retention. Excessive use can cause dehydration, so watch the dosage.

Breastfeeding – mums need and additional 2-3 cups of water a day to replace the fluid lost in breast milk.

Irritable bowel syndrome – diarrhea is a common symptom of irritable bowel syndrome and can cause dehydration.

Diabetes – excessive thirst is one of the symptoms of untreated diabetes. When blood sugar levels rise, the kidneys attempt to remove excess glucose by producing more urine. This removes increasing amounts of water from the body, leading to thirst and dehydration.

References

www.sportdietitians.com.au – Sports Dietitian Australia

www.nutritionAustralia.org – Nutrition Australia

www.betterhealth.vic.gov.au – Better Health Channel

Healthy Food Guide February 2016, page 42