Hydration - Your first act of self-care

Lisa Came
Oct 22
3 min read

We all know water is important, and that we should probably be drinking more of it, but it’s easy to forget just how much it does for us. Around 60% of your body is made up of water, and every cell depends on it to work properly. From keeping your temperature stable to supporting digestion, hormones, and energy, water quietly holds everything together.

Yet many of us go through the day slightly dehydrated, often reaching for coffee before water, forgetting to refill the bottle beside us, or only drinking when we feel thirsty. It might not seem like a big deal, but even mild dehydration can affect how you feel, think, and function.

Hydration and Hormonal Balance

Proper hydration is essential for maintaining hormonal equilibrium. Hormones such as cortisol, insulin, and antidiuretic hormone (ADH) are sensitive to the body's hydration status.

Cortisol Regulation: Dehydration can elevate cortisol levels, the body's primary stress hormone. Elevated cortisol can lead to increased appetite and fat storage, particularly in the abdominal region. A study published in The American Journal of the Medical Sciences found a correlation between dehydration and increased cortisol levels, suggesting that maintaining hydration may help manage stress responses and associated metabolic consequences.
Insulin Sensitivity: Hydration status influences insulin sensitivity. Adequate water intake helps maintain optimal blood glucose levels by supporting insulin function. Conversely, dehydration may impair insulin sensitivity, increasing the risk of insulin resistance and type 2 diabetes.
Antidiuretic Hormone (ADH): ADH helps regulate water balance in the body. When dehydrated, ADH secretion increases to conserve water, affecting kidney function and fluid retention. Chronic dehydration may disrupt this balance, leading to complications in fluid and electrolyte homeostasis.

Hydration and Weight Management

While hydration alone is not a magic solution for weight loss, it supports weight management through several mechanisms:

Appetite Suppression: Drinking water before meals can promote a feeling of fullness, reducing overall calorie intake. A systematic review in Obesity found that pre-meal water consumption led to greater weight loss compared to control groups.
Metabolic Boost: Water-induced thermogenesis refers to the energy expended to heat ingested water to body temperature. This process can modestly increase metabolic rate, aiding in calorie expenditure.
Fat Metabolism: Hydration is necessary for lipolysis, the breakdown of fats into fatty acids and glycerol. Without sufficient water, the body's ability to metabolise stored fat for energy may be compromised.

Hydration's Impact on Physical and Cognitive Performance

Hydration not only impacts the body, but it also plays a large role in our cognitive functioning. Even mild dehydration can impair physical performance, leading to fatigue, reduced endurance, and decreased strength.

Cognitively, dehydration can affect concentration, alertness, and short-term memory. A study in Nutrition Reviews highlighted that a 1-2% decrease in body water can impair cognitive performance, which emphasises the importance of staying hydrated.

Hydration and Digestive Health

Water aids in the digestion and absorption of nutrients. It helps dissolve fats and soluble fibre, preventing constipation by softening stools and promoting regular bowel movements, all of which promotes a healthy gut.

Recommendations for Optimal Hydration

Daily Intake: The National Academies of Sciences, Engineering, and Medicine recommends a daily water intake of about 3.7 litres for men and 2.7 litres for women, including all beverages and moisture-containing foods.
Keep Checking In: Pay attention to signs of dehydration, such as dark urine, dry mouth, fatigue, and dizziness. Urine colour is a practical indicator; pale yellow suggests adequate hydration.
Adjust for Activity and Environment: Increase fluid intake during hot weather, high altitudes, or intense physical activity to compensate for additional water loss through sweat and respiration.

Hydration affects almost everything: your hormones, mood, focus, digestion, and even how well you sleep. It’s one of those quiet habits that doesn’t demand much, yet makes a noticeable difference in how you feel each day.

So next time you fill your glass, take a moment to see it differently: not as another thing to tick off your list, but as a small act of self-care