Posts Tagged ‘dehydration’

Water, Water Everywhere-How Much Do We Need To Drink?

August 30, 2015

I graduated from medical school in 1968 with the advice to my patients to drink 8 glasses of water a day. If there is one health myth that will not die, it is this: You should drink eight glasses of water a day. It’s just not true. There is no science behind it. Yet the number of people who carry around expensive bottled water seems to be growing each day. A recent White House policy declared that 40 percent of Americans drink less than half of the recommended amount of water daily

There has been a fear that otherwise healthy adults and children are walking around dehydrated, even that dehydration has reached epidemic proportions.

Let’s put these claims under scrutiny.

There was a myth that people should drink at least eight 8-ounce glasses of water a day. The source of this myth was a 1945 Food and Nutrition Board recommendation that said people need about 2.5 liters or about two quarts of water a day. This report also pointed out that most of this quantity is contained in prepared foods. Water is present in fruits and vegetables. It’s in juice, it’s in beer, it’s even in tea and coffee. Before anyone writes me to tell me that coffee is going to dehydrate you, research shows that’s not true either.

Although I recommended water as the best beverage to consume, it’s certainly not your only source of hydration. You don’t have to consume all the water you need through drinks. You also don’t need to worry so much about never feeling thirsty. The human body is finely tuned to signal you to drink long before you are actually dehydrated.

Contrary to many stories you may hear, there’s no real scientific proof that, for otherwise healthy people, drinking extra water has any health benefits. For instance, reviews have failed to find that there’s any evidence that drinking more water keeps skin hydrated and makes it look healthier or wrinkle free.

Other studies fail to find benefits in kidney function or all-cause mortality when healthy people increase their fluid intake.

One possible exception is that drinking water may lead to the prevention of the recurrence of some kinds of kidney stones.

Bottom Line: There is no formal recommendation for a daily amount of water people need. That amount obviously differs by what people eat, where they live, how big they are and what they are doing. In New Orleans with high temperatures and high humidity, consuming more water especially when working or playing outside in the summer is probably a good idea.

Water-How Much is Enuf?

August 26, 2015

I graduated from medical school in 1968 with the advice to my patients to drink 8 glasses of water a day. If there is one health myth that will not die, it is this: You should drink eight glasses of water a day. It’s just not true. There is no science behind it.

These reports work up a fear that otherwise healthy adults and children are walking around dehydrated, even that dehydration has reached epidemic proportions.

Let’s put these claims under scrutiny.

There was ta myth that people should drink at least eight 8-ounce glasses of water a day. It made no difference. Many people believe that the source of this myth was a 1945 Food and Nutrition Board recommendation that said people need about 2.5 liters of water a day. But they ignored the sentence that followed closely behind. It read, “Most of this quantity is contained in prepared foods. Water is present in fruits and vegetables. It’s in juice, it’s in beer, it’s even in tea and coffee. Before anyone writes me to tell me that coffee is going to dehydrate you, research shows that’s not true either.

Although I recommended water as the best beverage to consume, it’s certainly not your only source of hydration. You don’t have to consume all the water you need through drinks. You also don’t need to worry so much about never feeling thirsty. The human body is finely tuned to signal you to drink long before you are actually dehydrated.

Contrary to many stories you may hear, there’s no real scientific proof that, for otherwise healthy people, drinking extra water has any health benefits. For instance, reviews have failed to find that there’s any evidence that drinking more water keeps skin hydrated and makes it look healthier or wrinkle free. It is true that some retrospective cohort studies have found increased water to be associated with better outcomes, but these are subject to the usual epidemiologic problems, such as an inability to prove causation. Moreover, they defined “high” water consumption at far fewer than eight glasses.

Prospective studies fail to find benefits in kidney function or all-cause mortality when healthy people increase their fluid intake. Randomized controlled trials fail to find benefits as well, with the exception of specific cases — for example, preventing the recurrence of some kinds of kidney stones. Real dehydration, when your body has lost a significant amount of water because of illness, excessive exercise or sweating, or an inability to drink, is a serious issue. But people with clinical dehydration almost always have symptoms of some sort.

A significant number of advertisers and news media reports are trying to convince you otherwise. The number of people who carry around water each day seems to be larger every year

This summer’s rash of stories was inspired by a recent study in the American Journal of Public Health. Researchers used data from the National Health and Nutrition Examination Survey from 2009 to 2012 to examine 4,134 children ages 6 to 19. Specifically, they calculated their mean urine osmolality, which is a measure of urine concentration. The higher the value, the more concentrated the urine.

They found that more than half of children had a urine osmolality of 800 mOsm/kg or higher. They also found that children who drank eight ounces or more of water a day had, on average, a urine osmolality about 8 mOsm less than those who didn’t.

So if you define “dehydration” as a urine osmolality of 800 mOsm/kg or higher, the findings of this study are really concerning. This article did. The problem is that most clinicians don’t.

A doctor can tell you that I have rarely, if ever, used urine osmolality as the means by which they decide if a child is dehydrated.

In other words, there’s very little reason to believe that children who have a spot urine measurement of 800 mOsm/kg should be worried. In fact, back in 2002, a study was published in the Journal of Pediatrics, one that was more exploratory in nature than a look for dehydration, and it found that boys in Germany had an average urine osmolality of 844 mOsm/kg. The third-to-last paragraph in the paper recounted a huge number of studies from all over the world finding average urine mOsm/kg in children ranging from 392 mOsm/kg in Kenya to 964 in Sweden.

That hasn’t stopped more recent studies from continuing to use the 800 mOsm/kg standard to declare huge numbers of children to be dehydrated. A 2012 study in the Annals of Nutrition and Metabolism used it to declare that almost two-thirds of French children weren’t getting enough water. Another in the journal Public Health Nutrition used it to declare that almost two-thirds of children in Los Angeles and New York City weren’t getting enough water. The first study was funded by Nestlé Waters; the second by Nestec, a Nestlé subsidiary.

It’s possible that there are children who need to be better hydrated. But at some point, we are at risk of calling an ordinary healthy condition a disease. When two-thirds of healthy children, year after year, are found to have a laboratory value that you are labeling “abnormal,” it may be the definition, and not their health, that is off.

None of this has slowed the tidal push for more water. It has even been part of Michelle Obama’s “Drink Up” campaign. In 2013, Sam Kass, then a White House nutritional policy adviser, declared “40 percent of Americans drink less than half of the recommended amount of water daily.”

There is no formal recommendation for a daily amount of water people need. That amount obviously differs by what people eat, where they live, how big they are and what they are doing. But as people in this country live longer than ever before, and have arguably freer access to beverages than at almost any time in human history, it’s just not true that we’re all dehydrated.

Water, Water Everywhere-Be Sure You Drink It

December 7, 2012

When exercising the general rule is to drink 24 ounces of fluid, especially water, two hours before exercising, followed by 8 ounces of water or sports drink (Gatorade) for every 20 minutes during your exercise.

Be on the look out for signs of heat-related dehydration, which include muscle cramps, fatigue, dizziness, nausea, and a sudden cessation of sweating. If you experience any of these findings, stop exercising and immediately drink some cold water.

Water, Water Everywhere-How To Figure What To Drink?

August 27, 2012

Example of Flavored Water


You go to the grocery store and instead of turning on the tap, you want to buy flavored water. There are several dozen choices including VitaminWater, Fruit20, Fruitopia, and Ozarka just to name a few. Many drinks labeled as water are loaded with sugar and empty calories. Even though these drinks have ‘water’ in their name, drinking them regularly may increase your calories and lead to obesity. What does one do with so many choices?

Here’s what to look for — and what to avoid.
1. Check the calories
Real water has zero calories. Always check the packaging label to see if a so-called water beverage has calories.
2. Watch out for sugar
Some so-called water drinks include sugar, fruit juice or other sweeteners. So, be sure to check the total carbohydrates and sugars on the nutrition label.
Your drink is only real water if the total carbohydrates and sugars are listed as 0.0 grams.
Over time, drinks with a lot of sugar and/or caffeine can lead to dehydration as large amounts of sugar and caffeine act like diuretics.
3. Don’t be fooled by added vitamins, minerals or fiber
It’s okay to occasionally drink a beverage with added vitamins, minerals or fiber. But beware: beverage companies often market these nutrients to trick you into thinking you’re getting something healthy — and to make you overlook the unhealthy parts of the drink, such as sugar.
Keep in mind that you should get your nutrients from fruits, vegetables, whole grains, healthy fats, and lean protein whenever possible — not from drinks.
4. Electrolytes aren’t usually necessary
Many drinks promise electrolytes and improved athletic performance. But in most cases, your body doesn’t need to replenish electrolytes unless you’re doing aerobic or outdoor activity for longer than 60 minutes. Regular water should provide the hydration you need.
My advice
Whenever possible, opt for filtered tap water. Not only will you save money; you’ll also reduce your exposure to toxins like Bisphenol-A (BPA), which may get into water that’s sold or stored in plastic bottles. Play it safe by keeping your filtered tap water in a glass container.
Try to drink at least 64 ounces — or 8 glasses — of real water each day. Your body needs this much water to stay hydrated and work efficiently. And, it helps you feel full longer so that you eat less and maintain a healthy weight. Research suggests that replacing sugary drinks with water may help you shed a few pounds.
Don’t like water? Cut up berries or an orange, lime or lemon and put them into your water for extra flavor. Added bonus: you’ll get some disease-fighting vitamins and antioxidants.
Bottom Line: Water is the elixir of life. Drink lots of it, especially filtered tap water and avoid the marketing hype of flavored waters. Drink up.

This blog was modified from an article by Mary Ellen Herndon, a dietitian at The University of Texas MD Anderson Cancer Center. The article appeared in Dr. Kevin Pho’s blog, http://www.kevinmd.com

What You Need To Know About Water

November 19, 2011

Did you know that water makes up about 65% of a person’s total body weight. After oxygen, there’s nothing more important to our survival than water.

Dehydration
The primary mechanism that we maintain our proper hydration is through thirst. Thirst serves two functions: 1) to regulate the volume of water within our bodies and 2) to control the concentration of various salts like sodium and potassium within the body. Fluid is lost through urination, skin loss by sweating, respiration, and a small amount in the feces, unless someone has diarrhea and then a significant water loss may occur. If there is a loss of water by any of the above routes or if the concentration of the salts in the blood stream increases, then the thirst mechanism kicks in, which is a strong drive to consume more fluids.

How much water to drink every day?
You have heard from early childhood that you need to drink eight, eight ounce glasses a day. This is probably a myth that is perpetuated many years ago from the Food and Nutrition Board, which estimated that the average total fluid loss each day was 64-80 ounces. The Board did not mention that 20% of our intake of fluid comes from food. Therefore, you don’t have to consume all of your total intake as water.

In addition to thirst, the color of your urine will serve as an indicator of your state of hydration. If you are dehydrated, your urine will be dark and yellow. This is a sign to increase your water consumption and the urine will turn to white or light yellow, which is sign of adequate hydration. If you are in a hot environment or participating in sports and are sweating, you will want to check the color of urine when you complete the workout or sports event. If the color of your urine is dark, you know you are dehydrated and you need to consume more fluids. Athletes can lose up to two quarts of fluid through sweat each hour. So whenever you are in warm or hot environment and you are losing lots of fluids by sweating, you must make an effort to consume more fluids.

What about sports drinks
A sports drink beverage is designed to help athletes rehydrate when fluids are depleted after training or competition. Ideally the sports drinks are intended to replace the electrolytes that is lost in sweat during exercise and sporting events. Sports drinks usually contain a lower electrolyte concentration than found in sweat and can actually worsen the dilution of electrolytes. It is far easier to drink water and a salty snack.

Caffeine-Culprit or Cure ?
There is a myth that drinks with caffeine are dehydrating. The truth is that caffeine serves as a weak diuretic and promotes an increase in urine output and the fluid intake will more than compensate for the diuretic effect of the caffeine. Like most things in life, anything in moderation is acceptable and this includes caffeine.

What about bottled water?
Millions of Americans are drinking bottled water. $22 billion is spent each year throughout the world on bottled water. Bottled water, although up to 1,000 times the price of tap water, may be no safer, or healthier than tap water. A gallon of bottled water is $3.84\gallon making it as expensive as gasoline. In addition to the expense, 1.5 million tons of plastic are used to bottle water and toxic chemicals can be released during the manufacture and disposal of the bottles. Studies have confirmed that microbes, pesticides, and solvents have been detected throughout groundwater supplies, and have subsequently found their way into bottles.

The Environmental Protection Agency checks the water that is consumed by the public. In the United States the quality of the water is very safe. If you live in an area and drink well water, you will want to have the water checked for contamination on a regular basis. A number of private water wells sampled in Louisiana showed potentially unsafe levels of arsenic, volatile organic compounds (VOCs) and pesticides, as well as secondary contaminants in standard system tests for pH, hardness, alkalinity, dissolved solids and manganese.

Bottom Line: Water is truly the elixir of life. Avoid dehydration by checking out the color of your pee. For the most part, tap water tastes just as good as bottled water and is a whole lot cheaper. Drink up!

Water-Nature’s Pefect Medication

June 14, 2011

For those of us living in southeastern Louisiana with very high humidity and high temperatures, we need increased consumption of water especially during the summer months. The tap water in our community is perfectly safe and it is not necessary to consume inexpensive bottled water. Tap water is far better than sodas, flavored waters, coffee and tea. In most situations you can rely on your thirst to determine how much water you need to drink. However with increased sweating and increase outdoor temperatures, consider increasing your fluid consumption. Other exceptions are patients who have a history of kidney stones need to increase their fluid consumption especially during the summer months.  Two rules of thumb: #1- you need to drink 1 cc of water for every calorie you’ve consume. For example, if you have a 2000-calorie per day diet, you will need two thousand cc of water per day or approximately 66 ounces of water.   #2-If you want to know how much water you need, consider looking at the color of your urine.  During the summer months the urine should be clear and white. If your urine is dark and yellow, that is an indication that you need to consume more fluids. So drink up and enjoy the summer and every now and then take a look at the color of your urine-your body and your health will thank you!