What it is:
Many of us are aware that water is essential for our daily functions, yet we regularly neglect our intake. Water is a significant component of all bodily fluids, blood pressure and makes up ~60% of our total body volume. Maintaining proper fluid levels is crucial to carry nutrients, oxygen, and waste to/from cells.
One of the standard statements for optimal health is that you should drink eight ounces of water eight times per day. But this idea is not based on proper research and doesn’t take into account our individual needs. So how much water do we truly need for optimal function?
The Purported claims:
Hydration is stated to resolve many issues, including but not limited to:
The removal of toxins + kidney health maintenance
Keeps the skin moisturized and prevents wrinkles
Helps maintain healthy bowel movement
Regulates body temperature
Boosts exercise performance
Lubricates the joints + protects from injury
Helps cognitive function + concentration
Prevents kidney stones
What the science says:
Hydration is much more than just water; it also involves all fluids and foods that contain water. Beyond that, hydration also involves electrolytes, which are essential minerals that are utilized in bodily functions, energy processes, and maintaining fluid balance.
Thirst is often used to measure hydration, but it is affected by multiple factors beyond hydration, like the food you eat. A more simplified approach to measuring hydration is through urine output, urine frequency, and color. When your body is dehydrated, it will reduce the total amount you're urinating, typically you will urinate less than six times a day, and your urine will be darker in color.
As stated before, hydration goes beyond just water. Many foods (especially- vegetables and fruits) and other beverages are excellent sources of fluid. Tea and coffee are the highest consumed liquids in the world, after water, and they can be hydrating -- depending on the type and amount you drink. Caffeine is a mild diuretic effect (causing increased urination), but typically anywhere between 300-500 mg of caffeine should not have adverse effects on hydration status. Alcohol is the one fluid that causes net losses to our hydration levels. Consumption should be moderate and followed with water or other hydrating beverages.
Severe dehydration (1% or more loss of total body mass) is rare in everyday life. Still, it might occur due to a weak immune system, sickness, high activity level, or lack of fluid intake, causing diarrhea and dizziness. Mild dehydration is more common and can cause brain fog, fatigue, intense thirst, and dark urine. However, some of these symptoms, like brain fog and fatigue, are also seen in overhydration. Overhydration is rare but can result in headaches and intense nausea. Those most at risk for overhydration are those who partake in endurance sports and drink excess water lacking electrolytes to balance fluids.
Hydration is highly individualized as it depends on what you eat, where you live (humidity, altitude, temperature), the amount and type of activity you partake in, and body composition.
All in all, there is no objective evidence to support the 8x8 rule and no universal consensus on how much water one should consume day by day. However, hydration and fluid intake is still important. Not all fluid needs to be water as we can achieve hydration through other beverages and foods.
Most research suggests that most healthy adults are drinking enough. However, it is unlikely for you to experience overhydration, and much easier to develop dehydration. Most typically, one should consume around 60-150 oz/day of fluids, including water, other beverages, and food. On just water alone, you should aim to consume approximately 30-50 oz/day.
You can consume filtered tap water via osmosis filters, home-filtration systems, or different types of food. These include but are not limited to apples, celery, cucumbers, grapes, lettuce, melons, oranges, peppers, and more.
Will this benefit you?
Yes, taking care of your hydration and being mindful of your hydration status will help you in your daily life and health.
You don’t have to be a stickler in tracking your water but generally aim to consume water with every meal and when you’re thirsty. It’s crucial to adequately hydrate pre and post-activity, often with the addition of electrolytes.
Still curious to know if you’re drinking enough? If you are, here’s what to keep an eye on:
Factors that alter your hydration needs:
Increased sweating; whether due to exercise intensity or temperature/humidity without proper rehydration
Drinking excess caffeine ( > 500 mg/day)
Fever or other sickness requiring more hydration (water + electrolytes)
Pregnancy + breastfeeding requires more fluids.
65+ older [Some studies have indicated that as we get older, our thirst mechanism declines, putting those who are 65 and older at a higher risk for dehydration]
If you are concerned with your hydration status and/or needs, contact your Apeiron Life Client Advocate to determine your correct daily fluid intake.
References and additional reading: