We humans look pretty solid. But more than half of our body weight is actually liquid—a briny fluid, much like the seawater that first nourished all primordial life. That fluid keeps us in good working order, cushioning and hydrating our cells, tissues, and organs, transporting nutrients, and eliminating waste from the body. So it’s really only half true that you are what you eat: You’re also what you drink.
In order to maintain a constant temperature and to dispose of waste, your body loses about half a gallon of liquid every day through sweat, exhaled air, and urine. On a hot day, you lose even more. Exercise vigorously, and you sweat off up to an additional quart of liquid an hour. And it all needs to be replaced.
When your body fluids are depleted, you become dehydrated. Extreme dehydration is not a concern if your diet is reasonably balanced, your activity level is not excessive, and you’re not stranded in a desert. But minor dehydration is sneakier, because it’s not always easy to spot. It can make you feel grumpy and tired and make it hard to concentrate. And if it becomes chronic, it can cause constipation and may even lead to kidney stones and bladder cancer.
Minor dehydration can be avoided easily by drinking enough fluids throughout the day. But if you tend to drink liquids only when you’re thirsty, you may not be drinking enough of them. Thirst does help you gauge your level of hydration, but it’s not quite as reliable a guide as you might assume. By the time you actually feel thirsty, your fluid level can often already be too low, and as you age, your sense of thirst tends to become an even less dependable indicator of dehydration.
It’s also important to recognize that thirst and hunger are both physiologically and psychologically driven. When you feel hungry between meals, what you may be experiencing is dehydration. In other words, when you think you’re hungry what you may be—even though you don’t realize it—is thirsty. But you reach for food without much thought and wind up overeating. Much of what the Eat, Drink, and Weigh Less program is about is being conscious of how you respond to cues of hunger and thirst throughout the day. The next time you feel a little hungry, try reaching for a glass of water. You may be surprised that the refreshment it brings you turns off that hunger switch until your next meal.
In general, your best bet is to just stay hydrated, regardless of how thirsty or hungry you feel, instead of waiting for cues from your body. How hydrated? Well, you need about a milliliter of fluid for every calorie you burn. That works out to about 64 ounces (8 cups) of liquid a day for a 2,000-calorie-a-day diet. Some of that liquid can come from food and the rest can come from pretty much any beverage at all. Drink a glass of something liquid between meals and a glass with each meal, and, if you follow the basic guidelines of the Eat, Drink, and Weigh Less program, you’ll have no problem staying hydrated.
But, that said, just as with fats, carbohydrates, and proteins, with liquids some choices are smarter than others. The good news is that the beverage at the top of the smart list is ubiquitous, inexpensive, thirst-quenching, and easy to love. You guessed it: water.
When it comes to hydration, water has 100 percent of what you need, with no calories or additives. And at less than a penny a glass (or, if you buy it bottled, still often less than you’d pay for lemonade or soda), it’s a bargain that’s hard to beat—especially when you compare it to the alternatives.
Remember our bottom-line truth: A calorie is a calorie. Drink water and you hydrate without adding calories. Drink regular soda or juice and you’re increasing your caloric intake. But, if you’re like most people, chances are you see “liquid calories” as somehow different from “food calories,” if you make note of them at all—and that’s a big if. So you may not be compensating for the calories you drink by eating less. Let’s look at a few of the most common beverage options in this light.
Sodas. Just how popular is pop? Sodas make up a staggering 25 percent of the liquids Americans drink. If you asked people how many teaspoons of sugar they wanted in their tea and they said, “Oh… seven, maybe eight,” you’d assume they were either crazy or six years old. But that’s how much sugar you’ll find in a typical 12-ounce can of soda. And who drinks just 12 ounces anymore, when that’s a “small” at most fast-food places?
The problem, of course, is that sodas deliver pure calories with no nutritional value. A soda a day may not sound like much, but if you didn’t eat less to compensate for its 150 calories, you could gain 15 pounds in a year!
And even if you do eat less or exercise more to make room for that daily soda, there’s the sugar issue. Taking in a megadose of rapidly digestible simple sugars in the relatively short time it takes to guzzle a soda triggers rapid, intense spikes in blood sugar and insulin, which, over time, may lead to diabetes and may also reduce blood levels of HDL (good) cholesterol and raise blood levels of triglycerides, increasing the risk of heart disease.
So, what about calorie-free sodas? They’re a better choice than the sugared kind, but still an expensive way to get water. The sugar substitutes they use (such as saccharin, aspartame, and sucralose) probably don’t present much of a health hazard, but the jury is still out about their effect on children who may consume large amounts of them over a lifetime. Diet sodas are artificially sweetened water. You’re better off drinking the natural version—flavored, if you like, with a twist of lemon or maybe a splash of juice, or brewed as an herbal iced tea.
So long, soda. If you’re a habitual soda drinker—at the level of one can a day or more—try this one-month experiment: Buy a case or two of single-serve bottles of sparkling water. Use them to replace the sodas in your home and office fridges. Choose waters flavored with citrus, if you like, as long as they don’t contain sugar. Reach for a sparkling water when the craving for soda hits. Opening the cap and holding a cool beverage in your hand will help, in a modest way, to satisfy your beverage urge. After a month, you’re likely to experience fewer soda cravings, and, if nothing else, to be much more conscious of them. If you can replace your soda habit with a water habit, you’ll stay hydrated and take in fewer empty calories every day.
Juice. Juice is water plus some vitamins, minerals, and maybe some fiber. It’s fine to start your day with a glass of juice, but remember that it adds a hefty dose of calories. Twelve ounces of orange juice, for example, gives you 168 calories—about what you’d get from three chocolate chip cookies. That’s a high caloric price to pay for quenching your thirst. And again, the problem with drinking fruit juice instead of water is that many people don’t compensate for the added calories by eating less. Most vegetable juices, by the way, have fewer calories than fruit juices, but check the label for both calories and salt before buying.
Dilution solution. Try cutting your juice with a little water, gradually increasing the dilution over time till you’re drinking one part juice to three parts water.
Much of what is sold as juice is really little more than fruit-flavored sugar water. Some “juice drinks” are obvious impostors, but others are harder to spot if you’re only looking at the name and the package. Check the ingredient statement, though, and you’ll see the difference immediately. Juice drinks—even those marketed as “juice” (often with fine-print qualifiers such as “drink” or “cocktail” in their names)—list water as the first ingredient, usually followed by high-fructose corn syrup and/or juice. Manufacturers put these drinks in splashy packaging with cues that say “fresh” and “light,” hoping you’ll reach for them as a healthy soft-drink alternative. But what you’re getting is lots of empty calories—and a beverage that’s nutritionally about the same as a soda.
Milk. An eight-ounce glass of whole milk contains 5 grams of saturated fat. Drinking three glasses of it a day would be the saturated fat equivalent of eating twelve strips of bacon or a Big Mac with fries. Those three glasses would also add 450 calories to your diet, and the same amount of low-fat milk would still add 330 calories. We don’t recommend milk as a daily beverage for adults. If you’re concerned about calcium, getting it from a calcium/vitamin D supplement is a better bet (see Chapter 7).
Coffee. Good news, java-lovers. Despite centuries of suspicion and misinformation about the evils of coffee, it turns out to be a remarkably safe beverage. Yes, caffeine is a drug, and like any drug, if abused, it can become addictive. Yes, people who become dependent on it may get nasty headaches if they miss their morning cup. But in moderation, coffee is low on the list of foods that pose health risks, and may even have some beneficial effects. Moderate coffee drinkers tend to see a lower risk of developing kidney stones, gallstones, and type 2 diabetes. And coffee’s antidepressant qualities are real and not insignificant. Suicide rates have been shown to be as much as 70 percent lower among coffee-drinkers as compared to non–coffee drinkers. The bottom line: Drinking a few cups of coffee a day in the context of a healthy diet and activity level doesn’t pose any health risks you need to worry about. (Keep in mind that we mean regular cups of coffee with modest amounts of low-fat milk and/or sweetener—and not serial lattés or highly sweetened variations on milky themes.)
In fact, drinking up to six cups per day of filtered coffee seems to have little adverse effect, except for the jitters and insomnia experienced by some people (who don’t often make the link between their coffee and these symptoms). A few studies have suggested a possible increase in fracture risk with four or more cups per day, but the findings are not consistent.
Tea. Black tea and green tea come from the same plant. The difference is in how they’re treated. Black tea is made by fermenting and drying the leaves of the tea plant. Green tea is made by steaming and drying tea leaves, without fermenting them. Both green and black tea contain caffeine—though in lower amounts than coffee—and the benefits that have been ascribed to coffee also apply to tea, including its mild antidepressant effect and its ability to help lower the risk of kidney stones and gallstones. There’s been a lot of speculation about green tea helping to prevent cancer. It has been suggested that flavonoids (a kind of phytonutrient also found in berries, apples, tomatoes, broccoli, carrots, and onions) in green tea may lower rates of some forms of cancer, but there’s been little clear scientific evidence to support this. Tea in moderation is fine. If you’re concerned about caffeine, decaffeinated and herbal teas are a good option—another way to get the water you need, with a bit of added flavor, warmth, and satisfaction. Note that yerba maté, an ingredient in some teas, contains caffeine.
Alcohol. In moderation, alcohol is probably good for most people, but not everyone. (See Chapter 6.)
Sports drinks. For strenuous exercise that lasts longer than an hour, sports drinks can be a good way to stay hydrated and fueled without stopping to eat. Sports drinks give you a quick hit of energy from glucose, and they restore electrolytes that can be lost with sustained vigorous activity. The glucose helps in the absorption of those electrolytes and also helps prevent hypoglycemia, which can occur after several hours of sustained hard exercise (the phenomenon athletes call “hitting the wall”). Drinks such as Gatorade don’t actually hydrate better than water, but because they’re flavored and sweet, you’re likely to drink them more often than you would water. If that works for you, fine. But for typical exercise activities such as cycling or walking for 20 to 30 minutes, your carbohydrate stores will be adequate if you eat slowly digested carbohydrates with meals (see Chapter 3) before exercising, and then just make a conscious choice to drink more water. Another solution, if you’re going to be exerting a lot of energy over a sustained period of time, is to drink diluted orange juice and munch on a few salty snacks. If your activity brings about continuous sweating, this is one of those rare times when taking some extra salt is a good idea.
When it comes to hydration, the best advice we can offer you is this: Stay hydrated, and make water your liquid of choice. If you like, include coffee or tea in the mix. A bit of juice is okay, but generally speaking, make the shift toward more water. The hydr-in “hydration” comes from the Greek word for water. Take that as a hint. It’s simply the best hydrator you can drink.
Six glasses a day. Drink a glass of water between each meal and one with each meal. Six glasses of water a day, plus a diet like Eat, Drink, and Weigh Less that includes plenty of vegetables and fruits, will keep you where you need to be.
Drink before you eat. Take the edge off your appetite by drinking a glass or two of water—or a cup of hot vegetable broth (here) a few minutes before you eat. You’ll feel fuller and you’ll be likely to eat less.
Water with meals, but… The one drawback to “washing your food down” with any liquid is that it can cause you to chew less, and chewing is an important part of breaking down your food for optimal digestion and absorption of nutrients—especially when you’re eating a lot of whole grains, legumes, vegetables, fruits, and other fibrous foods. So be conscious of how and when you sip and chew.
Move beyond aquatic apathy. Sure, tap water can be boring (and even revolting, if it’s highly chlorinated). If you have trouble motivating yourself—or even remembering—to drink more of it, you’re not alone. But make just about any conscious change in the way to think about, buy, serve, and drink water, and you’ll be prompted to drink more of it. Here are some suggestions:
• Treat yourself to bottled water. Of course, it’s more expensive than the “free” stuff that comes out of the tap, and in many communities, tap water tastes just as good. But manufacturers have created a whole industry around the psychological power of the bottle, and you can tap into that power, too. Keep small bottles of water in the fridge and “treat yourself” to them when you get the urge for a more caloric drink.
• Buy a water filter pitcher. Again, the effect is as much psychological as physiological. Regardless of what impurities that filter may be removing, the act of consciously filling the pitcher and putting it in the refrigerator keeps “water on the brain,” reminding you to drink it more often.
• Add sparkle. Sparkling water—whether it’s expensive imported mineral water or supermarket-brand club soda—is water. But it’s got that extra something that many people find gratifying. If that’s you, give yourself permission to buy it by the case and keep a few bottles in your refrigerator at all times. Try it a few times and it will become a habit—one that’s worth every penny it costs if it means you get the water you need. And sparkling water has the added benefit that it makes some people feel a bit more full than still water, thus helping them to eat less.
• Put it on ice. Simple, yet effective. Take a few extra seconds to scare up some ice cubes. They’ll make that glass of water more refreshing and pleasant to drink—and thus, less likely to languish on your desk or dinner table.
• Flavor your water. If even bottled water still feels boring and easy to forget, add a little flavor. Add a few slices of lemon, lime, or orange, or a splash of fruit juice to still or sparkling water to give it a little lift.
• Tea up. Keep a pitcher of iced herbal tea in the refrigerator to drink throughout the day. Get in the habit of brewing a cup of herbal tea to go along with between-meal snacks.
The principle here is straightforward: Drink plenty of liquids and avoid drinking empty calories. And for most of us, the easiest way to put that principle into practice is simply to make the shift from soda, juice, and other soft drinks to the clear, refreshing benefits of water.