Hydration for Health
The importance of understanding the body’s relationship with water.
Your body mass is 60 to 75 percent water. H20 is the foundational chemical formula that enables your body to function and is, truly, the foundational formula for all life on earth.
It is obvious that the body’s relation to this simple H20 formula is critical for function. Yet, amongst the noise of our day-to-day lives, we often struggle to meet even this most basic physiological need.
Being knowledgeable of the body’s biological needs creates a deeper and more informed mind-body connection. It’s difficult for the body to create healthy habits if the mind does not know its importance, especially in modern society where natural instincts are overshadowed by hectic lifestyles and unhealthy temptations. Connecting on a deeper level with our biological reality innately builds healthier habits, ultimately holding us more accountable for our wellbeing.
All of the cells, tissues, and organs of the body are mostly water. Being cognizant of this simple molecule can have a profound impact on physical and mental performance, and perceptions of wellbeing.
Cellular Health
There are two main compartments of water in the body: intracellular water and extracellular water. Our physiology relies on a precise balance between these two body water compartments. This balance is tightly controlled and regulated by a complex network of organs and their signaling molecules. The heart, blood vessels, kidneys, liver, intestines, and endocrine glands (hormones) all play important roles in balancing the body’s daily fluctuations in fluid. The importance of such tight control and regulation are profound. Even a two percent drop in body water results in disturbances in thermoregulation, mental acuity, and metabolic performance.
Many of us walk around with a lower than optimal balance of intracellular and extracellular water, or total body water. We typically don’t notice our poor hydration until the body systems become dysregulated and something in the body changes. Classic symptoms of dehydration are fatigue, brain fog, dry mouth, irritability, dizziness, confusion, and dark urine. The drastic difference proper hydration can make in the body showcases how even the most simple of health practices can have profound impacts on our lives.
What Water Does in the Body
Water serves as a medium for solubilization of nutrients and all metabolic reactions to take place. Let’s walk through water’s journey in the body, which begins by eating and drinking.
- All foods (many of which are a high percentage of water) combine with existing water in the body to create a digestible and absorbable solution. As nutrients travel through the blood, which contains plasma (roughly 90 percent water), to organs, they are absorbed by cells to be utilized.
- Absorption of nutrients takes place due to a phenomenon known as osmotic pressure. This is when water moves from areas of low solute concentration to areas of high solute concentration with the assistance of energy and specific nutrient transporters. Solute concentration refers to the amount of particles floating around in a fixed volume of fluid.
- Upon entry through cell membranes (which are mostly fat and water), nutrients undergo chemical processes that create energy and provide structures for genetic function. These chemical processes take place in the cytoplasm, which is a cellular “goop” and the main site of intracellular water.
- As metabolic chemical reactions that generate energy transfer from the cytoplasm into the mitochondria, which is a cellular furnace, nutrients from food burn to form energy. These chemical reactions subsequently create the by-product CO2 and (you guessed it) water.
- Every breath exhalation pushes out CO2 and water as a result of these energy producing chemical reactions, which rely on oxygen and nutrients from food. Therefore, in order to survive, humans must constantly replace oxygen supplies, food, and, yes, water.
Without water, the food we eat would not exist, our ability to digest and absorb food would be incomplete, and our utilization of nutrients to provide energy and structures that set the foundations for living would be impossible.
The story of water’s importance for the human body does not stop there. Water has a critical impact on blood volume and, subsequently, blood pressure. Fluid intake and output is a delicate homeostatic balance that is controlled by the brain, particularly the hypothalamus, and the kidneys. When blood volume is low, a message is sent to the brain to stop excreting water, to start drinking water, and to start holding onto sodium which draws water into blood.
Maintaining proper blood pressure and volume is important for a variety of reasons. Adequate blood pressure enables proper oxygenation of all tissues in the body and allows all cells of the body to survive and thrive. Meanwhile, if blood pressure gets too low, the body will feel weak and lose function. If blood pressure is too high, there’s a risk of long-term damage to blood vessels. Water is the key ingredient to this delicate balance.
Electrolytes
Electrolytes are small minerals needed in relatively small amounts that aid in increasing and maintaining hydration. The primary electrolytes for hydration are sodium, chloride, and potassium. Sodium and chloride increase water reabsorption into blood, and potassium balances urinary excretion. Other important minerals primarily received from food include magnesium, phosphorus, calcium, iron, zinc, copper, selenium, and chromium. You’ve probably heard of some of these minerals as they are tremendously important for optimal function and well-being. Nevertheless, the minerals that impact hydration the most are electrolytes.
When we excrete water from the body, we excrete electrolytes with it. The rate of excreting or reabsorbing certain electrolytes varies, therefore, the electrolyte balance is constantly in flux with the body’s hydration. To understand balancing electrolytes, let’s first discuss how we excrete water. We excrete water four primary ways:
- Breathing it out
- Excreting it out through urine
- Evaporating it out through the skin to regulate body temperature
- Sweating it out
As we excrete water and are tasked with replenishing it, it is advised to also replenish the electrolytes lost. Getting electrolytes can be simple, such as adding them into foods, eating a mostly whole foods diet, and structuring water. The simplest way to structure water is to add a squeeze of lemon and a dash of sea salt. There are also products designed specifically for electrolyte replenishment, such as LMNT. (I have no affiliation with this brand. I simply love the product and want to share it!)
Non-Water Fluids
All fluids can contribute to body water, yet, not all fluids are equal when it comes to optimal hydration. Water is certainly the most important fluid and it can be consumed in a variety of ways. Other fluids that contribute to a healthy fluid balance are coffee, tea, pure fruit juice, sports drinks, and milk. It’s important to be mindful when consuming non-water fluids as this should be done in moderation and everyone has different tolerance levels.
Certain beverages actually take away from hydration, like soda, sugar-sweetened beverages, flavored milk, juice with added sugar, energy drinks, and highly-sweetened coffee or tea. These beverages have a high concentration of sugar, which changes the osmotic pressures that influence the passing of fluid through the intestines and may pull water out of cells contributing to dehydration and increasing instances of diarrhea or loose stool. Minimizing consumption of these fluids will help keep the body hydrated.
And, of course, there’s our beloved libations. Alcohol actively dehydrates the body and disrupts the metabolism of other nutrients. Consumption of wine, beer, and/or spirits does not contribute to hydration and should be consumed in moderation.
A useful resource is this infographic by Precision Nutrition which illustrates how to approach fluids in the context of your goals and life. Check it out: What Should I Drink?
When to Hydrate?
The short and simple answer is all the time.
When you wake up, the first thing you do is urinate (usually). You also spent the whole night excreting water through your breath, sweat, and evaporation through the skin. It’s common to wake up with a two percent body fluid deficit. Therefore, it is critical for mental acuity and physical performance to hydrate first thing in the morning. Before having coffee and tea, make yourself an electrolyte cocktail: 16 oz. of water, a squeeze of lemon, and a dash of sea salt will do the trick.
After this morning ritual, consume fluids in small sips throughout the day. The baseline goal for water intake should be:
Your body weight (lbs.) x 0.5 = oz. of water per day
To make it even easier, divide this number by 33 to determine how many liters of water per day to drink. Or divide it by eight or 16 oz. depending on your preferred glass size and break it down that way.
If exercising, it’s best to consume small sips of fluid throughout to ensure adequate hydration. Chugging water can cause gastrointestinal discomfort, or “sloshing,” which can get in the way of athletic performance. Hydration needs for athletes and physically high-performing individuals are variable and dependent on many factors. These include location elevation, individual sweat rate, rate of electrolyte loss, bodyweight, and preferred fluids. For individualized hydration protocols for highly-active individuals, please reach out for a consultation.
Consume the majority of hydration throughout the day and wind down intake of fluids within an hour of bedtime. This is simply to avoid sleep disruptions for trips to the bathroom.
Tips for Better Hydration
The sensation of thirst is a survival mechanism that is often ignored to the detriment of our health and performance. There are many easy lifestyle changes that can be made to incorporate more water into your body and avoid dehydration or underhydration. Here are some tips for optimizing your hydration on a daily basis:
- Buy a one-liter water bottle that you can refill. Calculate your daily fluid requirements using the equation provided above and accommodate those fluid requirements throughout the day
- Set daily alarms or notifications as a reminder to drink water throughout the day
- Put a sticky note where you will see it often that says, “hydrate”
- Track your water intake with simple check marks for the number of times you refill your water bottle
- Remind yourself of the biological need for fluid and the physical and mental benefits of optimal hydration