There is a lot of information about drinking water on the web right now. I want to help you cut through the noise and get to the facts, so I’m publishing a short series on the why’s and how’s of hydration for plant-based eaters, especially plant-based athletes. If you’re interested in purchasing a water bottle, check out this list created for bicyclists. The same features of a well-designed water bottle carry over between cycling and any other sport.
We’ve all heard about the eight-glasses-a-day rule. Other sources say you should just drink when you’re thirsty. Still others say you should drink 1/2 ounce of water per pound of your bodyweight–or even 1 ounce per pound. Yeah, that’s a big difference. So who’s right?
First off, why do we drink water in the first place? According to the National Academies of Sciences, Engineering, and Medicine, water’s function in the body is to “Maintain homeostasis in the body and allow for transport of nutrients to cells and removal and excretion of waste products of metabolism.” Water does so much more than that (which we will cover in a future post), but that is a good summary. It is very clear that these functions are vital to our bodies’ health. Lack of water can lead to dehydration, which occurs when your body doesn’t have enough water to carry out normal functions. Even mild dehydration creates a domino effect of negative symptoms that we will explore in the future.
Back to the guidelines. The Institute of Medicine (IOM, housed within the aforementioned National Academies) set their water intake recommendation “for women at approximately 2.7 liters (91 ounces) of total water — from all beverages and foods — each day” and for men at “approximately 3.7 liters (125 ounces daily) of total water.” They further clarify that about 20% of daily water intake typically comes from food, the other 80% from all consumed beverages.
According to that guideline, the eight-glasses rule is woefully inadequate. That rule is actually 75 years old and doesn’t take into account the modern American diet (including greatly increased salt consumption) and lifestyle, among other factors. But is the IOM’s recommendation universally appropriate? Probably not.
When to Drink Extra Water
The Mayo Clinic provides some helpful clarification of the IOM’s rule. You should be drinking extra water if…
- You’re sweating from activity. “If you do any activity that makes you sweat, you need to drink extra water to cover the fluid loss.” Whether it’s your job if it’s strenuous, or a quick run, or a morning doing CrossFit, be sure to compensate by drinking an extra glass or two.
- You’re sweating from your environment. It goes without saying that if you live in a hot or humid environment, you’ll be sweating more and will need to drink more water to make up for it. High altitudes can also contribute to dehydration.
- You’re sick. “Your body loses fluids when you have a fever, vomiting or diarrhea. Drink more water or follow a doctor’s recommendation to drink oral rehydration solutions. Other conditions that might require increased fluid intake include bladder infections and urinary tract stones.”
- You’re pregnant or breastfeeding. This one is understandably very important. Whether you’re pregnant or breastfeeding, you’re responsible for your own hydration as well as your child’s. We learn by way of the Mayo Clinic that “the Office on Women’s Health recommends that pregnant women drink about 10 cups (2.4 liters) of fluids daily and women who breast-feed consume about 13 cups (3.1 liters) of fluids a day.”
Also, and this is just common sense, drink if you’re thirsty. That’s the brain’s way of telling you that you need to take action now to avoid dehydration. Time to down a glass and get back on track. Often, too, we confuse hunger with thirst, so if you’re feeling snacky, it’s smart to drink some water before eating more non-liquid foods that will require further hydration to digest properly.
How to Know if You’re Properly Hydrated
So far, so good. But those are still guidelines and estimates. Some would say that the best way to keep from dehydration is simply to wait until you’re thirsty to drink. But some of us have poorly regulated thirst mechanisms, or we confuse thirst with hunger. The best way to approximate whether you are fully hydrated in real time is to check the color of your urine. It should be pale yellow. I know, that’s not the silver bullet hydration measure you were expecting to hear, but there is a good base of scientific research that solidly supports this. As you note the color of your urine over time, keep track of how much water you’re drinking. When you have a couple days in a row where your urine maintains a pale yellow color, you’ve probably found your sweet spot for water consumption.
Here are the takeaways to help you make sure that you keep yourself hydrated as a unique individual with a unique body and a unique daily routine. Keep in mind the National Academies’ guideline of 91 ounces a day for women and 125 ounces a day for men. Don’t forget that you get about 20% of that from your food and don’t forget to count other beverages that you drink. After that, adjust upward if you’re sweating, sick, pregnant, or breastfeeding. Down a glass of water whenever you feel thirsty. And, bottom line, make sure your urine stays pale yellow.
In my next post, I’ll review the importance of proper hydration for the human body and especially for athletes. In the meantime, go buy a good water bottle and chug some H2O!