What you should know about drinking water (but probably don't)

Everything you need to know about the most essential part of your daily diet.

May 31, 2017, 9:09 AM NZST / Updated May 31, 2017, 9:08 AM NZST / Source: NBC News

By Brianna Steinhilber

As a kid, your parents are always telling you to drink more of it. In your 20s you down one between cocktails to stave off a hangover. As you get older you notice dry skin, under-eye circles and headaches creeping up when you don’t get enough of it. Gym rats carry around huge jugs of it, models swear by it as an essential piece of their beauty routine and a lack of it may just be the reason behind your daily afternoon slump..

We’re talking water — arguably the most essential component of our diets. (After all, we can’t survive more than a few days without it.)

As much as we glorify the beverage (rightly so) many of us aren’t getting enough: More than half of children and teenagers in the United States are not properly hydrated, according to a nationwide study from the Harvard T. H. Chan School of Public Health. The problem doesn’t stop when we enter adulthood: The Natural Hydration Council found that one in 10 consultations for tiredness and fatigue could be attributed to dehydration, and more than a third of the patients reported feeling better after drinking more water. The problem is, among the 300 general practitioners surveyed, just 4 percent believed their patients were aware of how to hydrate properly.

It may seem like a no-brainer — just drink more water. But do you know exactly how much you should be drinking?.

How Much Water Do You Need to Drink, Anyway?

We all know the eight-glasses-a-day rule, but is it something we should hang our hat on? While the goal certainly isn’t a bad one to aim for, the actual equation is more complicated.

“It is somewhat arbitrary as it doesn't take into account the size, activity, environment or diet of the individual,” says Dr. Barry Sears, leading authority on the dietary control of hormonal response and author of The Zone Diet.

So where did this guideline come from?

Dozens of factors can affect a person’s individual water needs, from exercising to sickness to the temperature outside.

“While no one knows for sure where the ‘8 x 8’ (which is eight, 8-ounce glasses of water) rule came from, it may have been adapted from the 1945 Food & Nutrition Board recommendation to drink about 2.5 liters of water each day,” explains Rima Kleiner, MS, RD and blogger at Dish on Fish. “The nice thing about the 8 x 8 water rule (which is about 1.9 L/day) is that it’s easy to remember, and it’s not too far off from the Institute of Medicine (IOM) general water recommendations of 13 cups (or 3 L) of water per day for men and 9 cups (or 2.2 L) of water per day for women.”

That being said, there are dozens of factors that can affect each person’s individual water needs, from exercising to sickness.

3 Key Ways to Avoid Dehydration

While you may not be able to determine an exact number of glasses that will ensure you remain perfectly hydrated at all times, there are some key steps you can take to keep you out of the dehydrated zone.

Don't Let Yourself Get Thirsty

The best indicator that you need to drink water? Thirst, says Dr. Sears. “The reason you have a sensation of thirst is because the lack of water alters the balance of salt in the blood and this imbalance causes a cascade of effects resulting in the desire (i.e. thirst) for greater hydration.”

Essentially, thirst is a symptom of dehydration.

“Our thirst sensation doesn’t really appear until we are 1 [percent] or 2 percent dehydrated. By then dehydration is already setting in and starting to impact how our mind and body perform,” says Lawrence E. Armstrong, one of the studies’ lead scientists, director of the Human Performance Laboratory at the University of Connecticut and an international expert on hydration who has conducted research in the field for more than 20 years. “Dehydration affects all people, and staying properly hydrated is just as important for those who work all day at a computer as it is for marathon runners, who can lose up to 8 percent of their body weight as water when they compete.”.

“Your thirst sensation doesn't really appear until we are 1 or 2 percent dehydrated. By then dehydration is already setting in and starting to impact how our mind and body perform.”

If you feel thirsty, it’s your body’s way of saying it’s dehydrated, says Kleiner. “Other signs of dehydration include altered mood, dry eyes, headaches or dizziness, muscle cramping, fever or lack of sweat.”

2. Check Your Urine Color for Tell-Tale Signs

There really is no magic number or formula for how much fluid you need every day, but the color of your urine is a pretty good indicator of where you stand on the hydration scale. “If your urine is colorless or pale yellow, you’re likely drinking an adequate amount of water," says Kleiner. "Mild dehydration may show itself in the form of bright or dark yellow urine. If your urine is darker than pale yellow or you’re feeling thirsty, then you need to drink some water.”

Sears agreed: “The best way [to tell if you're hydrated] is the color of your urine. If it's very pale in color, you are probably hydrated. The darker the color of the urine, the greater the hydration you require.”

3. Reach for Foods With High Water Content

One thing most of us fail to recognize is that our water intake isn’t only coming in a glass — the foods we eat make up a large chunk of our intake. “What wasn’t adapted was the part of the recommendation that suggested that most of this 2.5 liters would come from foods,” says Kleiner.

In fact, according to Kleiner about 20 percent of our total water intake comes from the food we eat. “Many vegetables and fruits are mostly comprised of water (some are more than 90 percent water), which really helps to contribute to our fluid intake and keep us hydrated,” she says. “And, all of those other beverages we consume (like milk, juice, beer, wine, even coffee, tea and soda) contribute to our fluid intake. But, don’t forget, other beverages (aside from water) contain calories.”

MORE STAY HYDRATED STRATEGIES

• 10 Smart Products That Will Make Upping Your Water Intake a No-Brainer

I Stayed Hydrated for Two Weeks and It Changed My Life

We tried three different methods to help us drink more water throughout the day. The results surprised us.

March 11, 2017, 5:47 AM NZDT / Updated Sept. 28, 2017, 3:05 AM NZDT

By Emily Slawek

Play The Video: https://www.nbcnews.com/better/diet-fitness/i-stayed-hydrated-two-weeks-it-changed-my-life-n731131

Is the secret to glowing skin, more energy and better health ... water?

We all know the old recommendation to drink eight glasses a day. But since the science on that is mixed, we wondered if we could actually feel and see a difference if we were properly hydrated.

To find out if water was the magical answer to all of our skin, sleep and mid-day slump dilemmas, two of my co-workers and I tried out three different methods to help us drink more water throughout the day for two weeks straight.

We spoke to Dr. Joshua Zeichner, a board-certified dermatologist with the American Academy of Dermatology, who gave us the standard eight glasses as a benchmark. Depending on lifestyle, weight, age, activity, medical conditions and other factors, the amount of water that each person needs will vary, but eight glasses a day should be the absolute minimum.

So we decided to set our goals at 3 litres per day for men (12 cups) and 2 litres (8 cups) for women.

Nick's method: Drink every time he does a new activity.

Nick’s challenge was to drink water every time he went to a new place. Go to the gym? Drink. Get to a meeting? Drink.

Gereldine’s method was to set an alarm on her phone every two hours, reminding her to drink water.

I tried out the smart wattle bottle method, H20 pal, which tracked how much water I was drinking throughout the day and reminded me to drink more..

The Challenges:

Our different methods had their pros and cons. Nick's activity trigger didn't always work for him. He had a hard time remembering to drink at certain times, so would force himself to drink extra water later.

Geraldine found the alarms inconvenient and annoying. She had a hard time keeping up her water intake at work — she had unexpected projects come up and found herself without a water bottle. And oddly enough on some days as she drank more water, she sometimes felt thirsty, so it made her drink even more water. She's not sure why.

For me, having my water bottle with me at all times was one of the most difficult parts of this challenge. I found it easiest to drink water when the bottle was quite literally in front of me, on my desk. When I was out and about, it was a bit harder for me to carry my water bottle everywhere..

Geraldine found the alarms irritating, but still drank her water.

Geraldine said her morning glass of water woke her up and made her feel so refreshed "it was amazing." She and Nick both felt more full from all the water, helping them cut down on snacks between meals.

Personally, I found that two litres of water didn’t make a huge difference for me. Toward the end of the challenge, I tried to drink four litres of water a day, which is when I really started to see a difference.

Pre-water challenge, whenever the clock would strike 2 pm, I’d have a headache. The afternoon slump and caffeine withdrawals were certainly real for me. Drinking more water throughout my day helped make my afternoons much more pleasant and headache-free, which made me more productive.

I didn't realize that I wasn't drinking enough water until this challenge. Being able to track how much water I'm drinking and assess how I'm feeling based on that has helped me realize that my body needs more water than I expected and that my afternoon headaches aren't from stress or a coffee (or three) too many, but were actually from being dehydrated.

After two weeks of this challenge, I’m still using H2O Pal. Despite how much I liked this water bottle, it is pricey at $99 and doesn’t keep my water cold for the entire day, like my beloved S'well bottle. The bottom of the bottle, where the tracker is, wasn’t the most secure, either — it fell off numerous times.

Still, Geraldine liked the effects of water so much — and disliked the alarms so intensely — that she's thinking of getting one, too.

Being an avid Apple Watch fan, I do love the connectivity of health trackers and found that using a smart water bottle was easy. Having a goal to reach, whether it be steps or glasses of water, has become part of my day and I like monitoring my progress.

MORE STAY HYDRATED STRATEGIES

• I Stayed Hydrated for Two Weeks and It Changed My Life https://www.nbcnews.com/better/diet-fitness/i-stayed-hydrated-two-weeks-it-changed-my-life-n731131

• What You Should Know About Drinking Water, but Probably Don't https://www.nbcnews.com/better/diet-fitness/down-low-h20-n760721