Hydration 101

Hydration: Why it’s so important, what counts as fluid, how much we need

Our society is in a perpetual search for the latest and greatest food, drink or supplement to boost energy, brain power and metabolism, but we often forget that one giant piece of the feel-good puzzle is all around us. And it’s cheap: water.

I was beyond happy to see a recent report from Beverage Marketing that we’re consuming more water, and fewer sugary soft drinks:  Our bottled water consumption has more than doubled since 2000, while our consumption of soft drinks has dropped each year for the past 11 years, with beverage industry analysts predicting that sales of bottled water could surpass soda by 2017.

We’ve been hearing the “drink more water” message for years, and now we’re actually doing it.

Athletes and people with active lifestyles aren’t the only ones who need to be concerned about optimizing their hydration.

In addition to regulating body temperature and reducing our risk of muscle cramping, heat exhaustion and heat stroke, staying hydrated is key for optimal brain function. Even subtle, low-level dehydration can negatively impact our energy, mood and alertness.  Water is essential for our bodies to transport nutrients and oxygen, and can be thought of as a “shock absorber” for our brain and spinal cords.

Thirst isn’t always a reliable indicator of how much we need to drink. Older people can have a reduced sensation of thirst, and, quite frankly, many of us are often too distracted and not tuned in to our body’s thirst cues, and we can easily miss the signs that we need to drink up.

How much fluid do we really need?

Many of us need more than the popular recommendation of “eight 8-ounce” cups of water.

The recommended “adequate intake” of fluid:

  • 3.7 liters (approximately 15 cups) per day for men
  • 2.7 liters (approximately 11 cups) per day for women

As a registered dietitian, I generally base my fluid recommendations on body weight, advising clients to aim for at least half of their body weight in ounces of fluid – plus another 16 ounces for every pound of sweat lost during exercise or work in the heat.

A 160-pound person, for example, would aim for 80 ounces of fluid daily as his minimum baseline fluid intake. Then, to determine amount of sweat lost, simply step on the scale before and after exercise or work in the heat – and add another 16 ounces for every pound lost, in addition to the baseline fluid needs.

What “counts” as fluid

Before panic sets in as you’re doing the math, note that the above recommendations are for total fluid intake – not just pure water.

Any fluid that doesn’t not contain alcohol can “count” toward our fluid intake – even coffee and tea can be included in our tally of hydrating beverages. The water in food also adds up:  Yogurt and cottage cheese are about 80 percent to 85 percent water, while some fruits are as much as 92 percent water, all inching us closer to our daily fluid goals.

Glass of water with lemon
Waters is the most inexpensive, easiest and purest way to stay hydrated, but all non-alcoholic liquids serve to hydrate us. (DevMarya, istock)

Best fluid sources

For most of us, the goal is to hydrate optimally, without adding a lot of calories, carbs, or sugars. So that means steering clear of drinks like sugar-sweetened soft drinks, lemonade, sweet tea, fruit juices and sports drinks.

Water is purest option, of course. And for those who prefer a little flavor and carbonation, there’s the option of all-natural, calorie-free sparkling waters like La Croix, Dasani Sparkling, or Target’s Simply Balanced sparkling waters.

Unsweetened tea (green, black, herbal, etc) and coffee are antioxidant-rich beverages that are essentially calorie-free.  And unsweetened almond milk (chocolate, vanilla, or plain) is very low in calories, with minimal carbs and almost no sugar.

For flavor on the go, Crystal Light makes a Crystal Light “Pure” stick pack for water bottles, with 15 calories per half-packet serving, and naturally sweetened with Truvia and a bit of sugar, with no artificial colors. I also like True Lemon andTrue Lime packets, which are made with crystalized lemon or lime juice and stevia, with just 10 calories per packet.

What about sports drinks?

I generally encourage clients to steer clear of sports drink, such as Gatorade and Powerade, even hard-training athletes, because these drinks are essentially sugary water with artificial dyes – and they’re not even that rich in electrolytes, compared to other sports drinks on the market.

G2 is a little better in the sugar department, but it’s still artificially colored, and artificially sweetened with sucralose and acesulfame potassium. And Propel at least doesn’t have artificial dyes, but it’s still artificially sweetened.

The sodium and potassium content of these traditional sports drinks is fine, but not phenomenal. A 12-ounce bottle of Gatorade or Powerade, for example, has 150-160 mg sodium and 35-45 mg potassium, for 80 calories and 21 grams of sugar (Gatorade is sweetened with pure sugar and dextrose; Powerade is made with high fructose corn syrup. And they both have those red, yellow, and blue dyes).

My top recommendation for an all-natural, low-sugar electrolyte-rich fluid replacer is nuun active. Each tablet (just add to water bottle) has 10 calories, one gram of sugar, 360 mg sodium, and 100 mg potassium – more than twice the electrolyte content of regular sports drinks.  I also like Vega Clean Energy as a sports drink alternative – one scoop has 100 calories and 20 grams sugar (from lower-glycemic coconut palm nectar), with 125 mg sodium and 115 mg potassium, with the added boost of 80 mg of caffeine, from black and green tea.

The bottom line:

Optimal hydration doesn’t have to be complicated. Most of us need at least 11 to 15 cups of fluid daily, but this can come from a wide range of drinks and even food. Set a schedule for how much to drink and when, if needed. It may feel like a hassle at first, but if the reward is more energy, fewer headaches, and less muscle cramping, it just might be enough incentive to drink up.


Editor’s note: Registered dietitian Molly Kimball offers brand-name products as a consumer guide; she does not solicit product samples nor is paid to recommend items.

Molly Kimball is a registered dietitian in New Orleans. She can be reached at eatingright@nola.com. Comment and read more atNOLA.com/eat-drink. Follow her on Facebook: facebook.com/mollykimballrd and Twitter:twitter.com/mollykimballrd.

DISCLAIMER: The information on this site is not intended or implied to be a substitute for professional medical advice, diagnosis or treatment. All content, including text, graphics, images and information, contained on or available through this web site is for general information purposes only.