Water plays a vital role in keeping the human body functioning at its best. It supports organs, regulates temperature, transports nutrients, and protects tissues. Because water makes up such a significant portion of the body, even mild changes in hydration can impact how you feel and perform.

Here are 5 fascinating facts about water in the human body that highlight why daily hydration—especially with clean, natural spring water—matters so much.

Men Have Higher Total Body Water (TBW) Than Women

Water percentages differ across genders, ages, and body composition. According to Dr. Jeffrey Utz (Neuroscience & Pediatrics, Allegheny University):

• Babies: Born with about 78% water, decreasing to 65% by age one
• Adult men: ~60% water
• Adult women: ~55% water

Fat tissue contains less water than lean tissue, and women naturally have a higher fat-to-muscle ratio—resulting in slightly lower total body water.

Research on normal-weight individuals found:

• TBW% is similar (62%) in boys and girls aged 3–10
• In males, TBW% stays stable until older age, then drops to 57%
• In females, TBW% drops earlier (11–20 years) to 55%, then decreases to 50% in women aged 61+

This shows that hydration needs can vary considerably throughout life.

Adults Lose 2.5 to 3 Litres of Water Every Day

The body continually loses water through breathing, urine, bowel movements, and skin evaporation—even when you aren’t sweating. Typical daily water loss:

• Adults: ~2.5 to 3 litres per day
• Equivalent to 4% of total body weight

If you weigh 70kg, you naturally lose around 2.5–3L per day and must replace it through drinking water and water-rich foods. Without replenishment, dehydration can build up over time and affect energy, focus, digestion, and overall health.

You Lose Around 1.5 Litres of Water During a 3-Hour Flight

Ever wondered why your nose, throat, and skin feel dry on planes? Airplane cabins have extremely low humidity because most circulating air is drawn from outside the aircraft—where high-altitude air contains little moisture. As a result:

• A passenger can lose ~1.5 litres of water on a 3-hour flight
• Long-haul flights increase dehydration risk significantly
• Symptoms include dry skin, headaches, fatigue, and increased thirst

Drinking water regularly on flights is crucial, and natural spring water is ideal because of its balanced minerals and refreshing taste.

Water Loss Increases in Heat and During Exercise

In hot weather or intense physical activity, the body cools itself through sweating, which dramatically increases water loss. Key findings:

• Hot environments rely mainly on sweat for cooling
• Water loss can reach 3–4 litres per hour with heat + vigorous exercise
• Daily water loss may exceed 10 litres in athletes or outdoor workers

While men often sweat more, research shows that trained women respond similarly to men at equal workloads, meaning both need to stay equally mindful of hydration during exercise.

Water Loss Must Be Replaced — Even a 1% Drop Matters

Inadequate hydration, especially over days (chronic under-hydration), raises risk of heat exhaustion or more serious heat-related illness. Loss of as little as 1% of body weight due to dehydration can have noticeable effects; a 10% water loss can be life-threatening.

When the body loses water, performance and wellbeing decline quickly:

• 1% loss of body weight: noticeable effects (thirst, fatigue, reduced concentration)
• 3–5% loss: headaches, dizziness, heat exhaustion risk
• 10% loss: potentially life-threatening

Chronic under-hydration raises the risk of heat exhaustion, poor cognitive performance, kidney stress, muscle cramps and low energy levels. Regular, consistent intake of drinking water is the simplest way to stay healthy and protect your body long-term.

Stay Hydrated & Rehydrate with Kulnura Spring Glow

Kulnura Spring Glow provides pure, refreshing hydration from a natural spring located 120 metres beneath Kulnura, New South Wales. Naturally filtered through sandstone, it contains:

• Light natural minerals
• Soft, smooth texture
• A subtle hint of natural sweetness

Perfect for supporting your body’s daily hydration needs.

Kula Aqua – Premium Natural Spring Water

• Perfect for everyday activities and an active lifestyle.
• Available sizes: 330ml, 500ml, 600ml, 1L, 1.5L, 5L
• Premium design. Keep hydrated and stay stylish.

Kulnura Spring Glow 15L – Big Hydration for Big Purposes

• Ideal for: Offices; Families; Cooking; and Outdoor gatherings
• Available with tap (instant drinking) or without tap (for water dispensers).

Email sales@kulnuraspring.com.au for enquiries or to explore our monthly deals.

Sources

Better Health Channel, & Victoria State Government | Department of Health. (2023, December 5). Water – a vital nutrient. Https://Www.betterhealth.vic.gov.au/. https://www.betterhealth.vic.gov.au/health/healthyliving/water-a-vital-nutrient

Khalil, S. (2023, April 27). What happens to your body on a flight. Https://Www.news.com.au/. https://www.news.com.au/travel/travel-advice/flights/why-you-need-to-keep-hydrated-on-a-flight/news-story/b2c00490b20437cfd655ae66579ca195

Lu, H., Ayers, E., Patel, P., & Mattoo, T. K. (2023). Body water percentage from childhood to old age. Kidney Research and Clinical Practice, 42(3), 340–348. https://doi.org/10.23876/j.krcp.22.062

Mayo Clinic. (2022, October 12). Water: How Much Should You Drink Every day? Https://Www.mayoclinic.org/. https://www.mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/in-depth/water/art-20044256

USGS. (n.d.). The Water in You: Water and the Human Body. Https://Www.usgs.gov/. https://www.usgs.gov/water-science-school/science/water-you-water-and-human-body#overview