Chapter 1: Can You Really Drink Too Much Water?

It’s 10:30 a.m., and I find myself heading to the restroom for the fourth time today. My morning started at 6:30 a.m. with a trip to the bathroom, followed by a glass of water and three cups of coffee, leading to several more restroom visits. Now, here I am again.

My urine is clear—almost always. If I consume another couple of glasses of water before lunch, followed by five more in the afternoon and evening, I’ll meet the widely accepted guideline of drinking eight glasses a day, a standard many believe is crucial for maintaining health and hydration. It’s likely I’ll make a dozen trips to the restroom by day’s end.

Until recently, I believed I was following the right advice. As the saying goes, water is vital for life. Dehydration is considered harmful, while ample water intake is deemed beneficial. However, a 2019 study published in the journal Nutrients caught my attention, discussing the potential hazards of excessive hydration. The authors argue that not only is drinking too much water wasteful, but it could also result in serious health issues like bladder distention and kidney dysfunction over time. They cited cases of otherwise healthy individuals who consumed so much water that they experienced swollen kidneys or ruptured urinary tracts.

The research surrounding hydration and its impact on longevity is surprisingly sparse, leading experts to describe the quest for a universal daily water requirement as "elusive."

“Urine serves as a waste product that helps regulate sodium and electrolyte levels in your body,” explains Tamara Hew-Butler, PhD, the primary author of the study and an associate professor of exercise physiology at Wayne State University.

If you find yourself urinating frequently and your urine is clear, she points out, it may indicate that you are consuming more water than your body actually needs, prompting it to expel excess fluids to maintain balance. While this isn’t likely to pose immediate concerns, maintaining this pattern over years could lead to urinary tract complications.

The more I explored the research, the more I recognized her perspective.

How much water should you actually drink daily for optimal health? The findings on hydration are surprisingly inconsistent. The long-standing recommendation—often referred to as the "eight-by-eight rule"—suggests drinking eight 8-ounce glasses of water each day. Yet, experts have struggled to find solid scientific backing for this advice.

“Saying everyone requires eight glasses of water to be healthy is akin to stating everyone needs a 2,000-calorie diet,” Hew-Butler notes. “I weigh 90 pounds and spend most of my day indoors, while I work with football players who weigh 300 pounds and are active throughout the day. Our hydration needs are vastly different.”

According to her, the average individual needs to replace approximately two liters (or eight cups) of lost fluids daily. However, nearly everything we consume contains water, which contributes to offsetting that loss. “Coffee, tea, soups, fruits, and vegetables all contribute,” she adds. Studies indicate that people may obtain about 20% of their daily fluid intake from food alone.

After examining samples from over 300 college athletes, she and her team discovered that up to 55% were dehydrated based on urine analysis, yet none showed dehydration in their blood tests.

Major health organizations exhibit significant variation in their recommendations for fluid intake. The European Food Safety Authority suggests that women and men should aim for two liters and 2.5 liters per day, respectively. In contrast, the U.S. National Academy of Medicine advises women to consume 2.7 liters and men 3.5 liters—approximately 35-40% more than their European counterparts. Both organizations, however, assert that all foods and beverages contribute to these daily totals.

It appears that the eight-glasses-a-day guideline has endured partly because no compelling alternative has emerged. Despite the lack of decisive research on water consumption's impact on longevity, experts have labeled the search for a universal daily requirement as "elusive."

The challenge in determining human hydration needs also relates to how dehydration is assessed.

In another study by Hew-Butler, urine-based hydration assessments—the most frequently used in research—often do not align with more accurate blood-based measurements. After analyzing samples from over 300 college athletes, she found that while up to 55% were classified as dehydrated by urine tests, none were dehydrated based on blood analysis.

There have been notable studies indicating that even mild dehydration can lead to fatigue, headaches, irritability, and cognitive difficulties. Surprisingly, some critiques of this research exist. A review published in Nutrients argued that such dehydration studies often yield inconsistent results, typically involving participants exercising in hot conditions, which could induce fatigue for reasons unrelated to hydration. Furthermore, many of these studies were conducted by researchers affiliated with companies that market bottled water.

Research featured in Nutrition Reviews has concluded that overhydration “may not be as harmless as commonly believed.”

While there is no doubt that dehydration poses risks—especially since our thirst signals tend to diminish with age—excessive water consumption can also lead to its own set of problems.

Moreover, the environmental implications of excessive water consumption are worth considering. Water is a limited resource, and energy is required to purify it for consumption. Many prefer bottled water, contributing to the staggering 28 billion plastic bottles used annually in the U.S. “If you're concerned about climate change, why would you consume more water than necessary?” Hew-Butler questions.

She advocates for drinking water when you feel thirsty. “Pay attention to your body,” she advises. “It will signal if you’re not drinking enough.” Dark yellow urine is a clear sign that it’s time to hydrate.

Water is undoubtedly beneficial. However, as with many things, it’s possible to have too much of a good thing.

The first video titled "What If You Drink Too Much Water? | Water Intoxication | Overhydration Side Effects | Dr. Binocs" explores the consequences of excessive water intake and its effects on health.

The second video, "What Happens When You Drink Too Much Water," delves into the physiological impacts of overhydration and dispels common myths surrounding water consumption.