Checking your urine plays a key role in your daily hydration habits
By Dr. Jamin Brahmbhatt, CNN
(CNN) — One recent weekend, I didn’t drink much while out in the sun. That Monday morning, after seven hours of sleep, I still felt exhausted. I was irritable, moody and unfocused.
My first instinct was coffee, which only made me jittery. Then I realized I was dehydrated. I drank two bottles of water over the next hour — and felt like myself again. Hydration restored my body’s balance.
We hear so much about daily water requirements, and like you, I aim to drink mine carrying reusable water bottles in every shape, color and size. What you might not hear as much is that it’s not just water in — it’s water out.
Patients, even those with no kidney stone issues, always ask me, “How much water should I drink?” It’s one of the most challenging questions to answer because there’s no one-size-fits-all. As a urologist — and as a kidney stone patient in recovery, I stress this advice: The goal isn’t ounces in, it’s urine out. Here’s what else to know about developing a healthy water habit.
Water matters to your body
Your body is about 60% water. That fluid lives inside your cells, between them and in the bloodstream. It cushions organs and joints, carries essential nutrients and hormones, clears waste and helps keep your body temperature in check.
Water also works in conjunction with electrolytes, such as sodium, potassium and chloride. They help your muscles contract, your nerves fire and your blood pressure stay balanced. If water intake falls behind losses, electrolyte concentrations can shift. That’s why dehydration can show up as muscle cramps, dizziness or even an irregular heartbeat.
When you’re even mildly dehydrated — as I was that weekend — the body has to work harder to maintain balance. Blood becomes more concentrated, the heart must pump harder, and the brain feels the strain — fatigue, fuzzy thinking, slower reaction time. Digestion can also slow down since water helps move food through the gut.
On the flip side, overhydrating without enough sodium — especially during endurance exercise — can be just as dangerous. It dilutes sodium in the blood, which can lead to confusion, nausea and in extreme cases, seizures. That’s why balance matters: Hydration is not just about water, but water and electrolytes working together.
How much water do you really need?
Most people immediately freak out when I suggest about eight to 10 glasses of water a day. That’s because they realize they’re nowhere close. And to be honest, unless I’m actively paying attention, I don’t always hit that number either. That’s OK. The truth is, some people need more, and some need less. And it can be harder to do when you’re doing shift work or traveling or facing any other number of reasons.
The standard advice is about 3.7 liters or 125 ounces per day for most men and 2.7 liters or 92 ounces per day for most women — from all sources, not just glasses of water, according to the National Academy of Medicine, formerly the Institute of Medicine. Roughly 20% of that typically comes from food. Think of these numbers as a starting point, not a hard limit.
Remember it’s also how much urine you produce: Urology guidelines recommend producing at least 2.5 liters of urine a day to lower stone recurrence.
Water needs depend on your body size, activity level, the climate you live in and even the medications you take. A one-size-fits-all number doesn’t exist. That’s why I like the simple “urine color check” more than counting ounces.
A simple self-check for hydration status
Now look at your urine. Yes, really. Aim for pale yellow throughout the day. Medium to dark yellow usually means you’re behind. Vitamins and some foods can change the shade, and your first pee of the morning will almost always be darker — that’s normal.
If you want to go deeper into what urine color, clarity and even odor can reveal about your health, I wrote about it here.
Some days call for more water: when it’s hot or humid, you’re doing a long workout, you have a fever, you’re nauseous or have diarrhea, you’re doing high-altitude travel or eating a salty meal.
In the heat, steady sipping is best — about 8 ounces every 15 to 20 minutes. Don’t exceed 48 ounces (1.5 quarts) in an hour, or you risk dangerously low blood sodium. Think of this as a water marathon, not a sprint.
Hydration is important for urinary tract infection prevention in both men and women. Want proof? In a randomized clinical trial of premenopausal women prone to recurrent UTIs, those who increased their water intake by about 1.5 liters daily experienced 1.7 infections over a year, compared with 3.2 in the control group — a nearly 50% reduction. They also required fewer antibiotics (1.9 courses versus 3.6).
Drinking too much water can be dangerous
Overhydration — especially during endurance activities — can dangerously dilute blood sodium, a condition known as exercise-associated hyponatremia. Marathon runners collapsing at the finish line often drank too much plain water, not too little. If you’re running long distances in the heat, combine water with salt — through sports drinks or salty foods.
If you have chronic conditions such as kidney disease or heart failure, be extra cautious. Your body might not handle large fluid loads well. In these cases, drinking excessive amounts can overload your system, causing swelling, shortness of breath or dangerous electrolyte imbalances. For these individuals, fluid intake goals should always be tailored with your doctor’s guidance.
What type of water is best?
Plain water is ideal, but it’s not the only way to meet your hydration needs. Coffee and tea count for regular caffeine consumers. In fact, controlled studies show that moderate coffee hydrates about as well as water. Alcohol does the opposite — drawing fluid out.
Regarding the many types of water at stores — alkaline, spring, reverse osmosis, “structured” water — most are marketing gimmicks, not medical essentials. Your kidneys don’t care if your water is from a mountain spring or your tap filtered at home. What matters is consistency, not branding. If a particular type encourages you to drink more because you like the taste, that’s fine. But don’t feel pressured to pay extra for gimmicks.
If plain water isn’t your thing, add a squeeze of lemon or fruit slices. A few drops of flavor enhancers — such as squeezable sweeteners found in grocery aisles — can also make water more enjoyable. The best water is the one you will actually drink throughout the day.
For extended, sweaty activities, add electrolytes or salty foods to replace sodium along with water. For everyday life and moderate exercise, water plus a balanced diet is usually sufficient.
It’s the same thinking with water bottles: The “best” water bottle is the one you’ll use. If a specific style or gadget encourages you to drink more, that’s great. But don’t let marketing convince you that the container matters more than the habit. Keep it simple — just drink.
My personal hydration routine
For me, drinking water has to fit into my daily routine. Between surgeries, I grab a glass of water — if I have seven cases, that’s seven built-in breaks to hydrate. In the clinic, I drink less because I’m constantly moving between patients, but I make up for it during lunch and on the drive home. I also consume two to three protein shakes a day. They remind me that fluids come from more than just water bottles.
We often think about water only during emergencies — such as hurricanes or heat waves with empty store shelves. But the real success lies in making hydration a daily habit, not a panic-buying response.
Set a realistic baseline, monitor your urine, adjust as needed, and respect heat and activity-related limits. Simple, consistent habits keep you hydrated — and that’s the plan I follow.
And yes — as I finish writing this, I’m drinking from a water bottle I picked up at the CNN souvenir shop. Proof that sometimes, the best hydration plan is the one you’ll stick with — even if it has a logo.
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