Ten Myths About Staying Hydrated

What do you think about your drink? Is what you have heard about hydration more hype than fact? Here are ten common myths about the human body's water needs and the facts that correct them.

Myth 1. Everybody needs the eight glasses (4 liters) of water every day.

There is no scientific basis of any kind for the often-quoted recommendation that everyone needs eight glasses of water every day. A study of stomach cancer in Asia found that the benefits of additional hydration are statistically significant at 5 cups (1200 ml) of water per day, that is, if you get at least that much water (and, in the Asian study, if you are male), then you are less likely to get stomach cancer. No claims for the health benefits of drinking more than that are to be found in the scientific literature. The Dietary Reference Intakes from the National Academies of Sciences, Engineering and Medicine’s Health and Medicine Division recommend 13 cups (a little over 3 liters) of total beverages for men and nine cups (a little over 2 liters) of total beverages for women as the average adequate daily intake for proper hydration in temperate climate. But heat, physical activity, infection, and salt intake can necessitate greater intake, just not as much as 4 liters of just water every day.

Myth 2. You need to drink before you get thirsty.

If you have ready access to water and other beverages, there is no need to play camel to make sure you don't get dehydrated. Your sense of thirst will let you know when you need to drink something. There are a couple of exceptions to this rule. If you working outdoors, or doing heavy exercise outdoors, in hot weather, then, yes, you do need to stay a little ahead of your thirst. Some older people may have a compromised sense of thirst and may need to make double sure they get enough to drink every day to avoid dehydration. Most of us, however, can wait until we feel thirsty.

Myth 3. The best way to rehydrate is with a sports drink.

It's absolutely true that muscles that have been worked out to the max need a combination of amino acids, glucose, electrolytes, and water to rebuild themselves and grow stronger. It's also true that a sports drink provides those nutritional needs very efficiently for people who have been physically active for at least an hour at a time. However, it's not true that you need a sugary sports drink every time you get sweaty from activity in the heat. Water and just a little fruit or fruit juice (10 grams/ one-half ounce of fruit or 30 ml/ one-eighth cup is enough) is all you to prevent dehydration in adults unless you have been working out very hard. Distilled water is never an optimal choice for rehydration.

READ Abnormal Urine Color: What It Tells (And Doesn't Tell) About Your Health

Myth 4. Dark urine is always the most important of all dehydration symptoms.

This myth is wrong on two counts. Many other issues can cause dark urine, including liver and kidney diseases. Also, in heat stroke, there can be a phase in which large amounts of clear urine are passed, followed by dark urine, followed by no urination at all. Sometimes what is needed is more fluid, sooner, especially when small children become dehyrated. Sometimes drinking a lot of water only obscures a liver or kidney problem.

More Myths About Hydration Busted

One of the most troubling myths about hydration and dehydration is the following:

Myth 5. People who are dehydrated always look "dry."

Dry skin, particularly dry skin that you can "pull," is a sign of dehydration. However, sometimes the body's water is "compartmentalized." The problem is that your cells, including your skin cells, can't pump water back into the bloodstream. This usually occurs as a result of diabetes, and is most common in people who consume too much of both sugar and salt.

Myth 6. Drinking water will hydrate your skin.

Your skin will look grayish and vaguely dusty if you don't get enough water, but you can be well hydrated and still have dry skin if you have circulatory problems. Splashing a little water on your skin, or applying a moisturizer that restores your skin's ability to retain water, of using mineral waters on your skin before you apply makeup, are better ways to achieve a dewy, soft complexion.

Myth 7. Coconut water is "super-hydrating."

There are many virtues of coconut water, the less it has been processed, the better. Coconut water is a good, fast source of a small amount of sugar. Coconut water provides electrolytes. Coconut contains chemicals that fight infection. However, there is nothing about coconut water that makes it better for hydration than ordinary water. An American marketer of coconut water, Vita Coco, had to pay heavy fines for making an unsustantiated claim that coconut water is super-hydrating.

Myth 8. Coffee and tea are dehydrating.

Caffeine is in fact a diuretic. It forces your kidneys to expel water. However, the diuretic effect of caffeine is less than the hydrating effect of coffee or tea, so you can drink either of them without worry of dehydration.

READ The Good And Bad Of Coffee

Myth 9. All foods are equally hydrating.

There is water in all foods, even the dryest zwieback or the saltiest salted cod. (Salted fish that hasn't been soaked, however, is definitely dehydrating.) Some foods, however, are far more hydrating that others. There is more water in a piece of fruit or a salad than in meat or cheese. You'll get more hydration by eating mimimally processed, lightly salted plant foods than by eating heavily salted animal foods. "Moist" foods, however, can do something for you that simply drinking water cannot. Your stomach quickly sends water on to the large intestine for absorption. A moist food like a stalk of celery, however, takes more time to digest than a well-chewed cracker. The longer your stomach takes to digest food, the less you want to eat, and the less weight you gain.

Myth 10. Drinking water won't really help you lose weight.

Health experts spent so many years pushing the idea that drinking water helps people lose weight that there has been a kind of backlash at the idea. The fact is, well-hydrated cells burn fats more efficiently. You can't have well-hydrated, fat-burning cells if you don't drink enough water. However, consuming lots of sugar can limit the benefits of drinking water, because the transportation of glucose into a cell is accompanied by an influx of sodium. Water-logged cells don't burn fats well, either. The effect of getting a few cups more water a day while limiting your sugar consumption is limited, but it helps dieters lose and additional 2 pounds (a kilogram) every two months, and it encourages the loss of fat, not muscle.