In recent years, celebrities and environmentalists have been giving up bottled water in favor of filtered tap water. It’s all part of the “green” movement.

And it’s past due. Just imagine how much fuel is burned transporting a billion bottles of water into and around the country every week. And that doesn’t include the petroleum products used to make all those plastic bottles or the environmental effects of tossing 38 billion of them into landfills every year.

Filtering your own tap water makes sense on many levels. Most of the billions of dollars worth of bottled water sold annually in the U.S. is simply filtered tap water. Furthermore, it costs about six bucks a gallon, and imported water can cost two or three times as much. And you thought gasoline was expensive!

But I digress. My real point is to show you how you can prevent or even reverse disease just by increasing your water intake.

Water, water everywhere

Water is the largest constituent of the human body and the medium in which most biochemical reactions occur. It’s required for digestion and absorption of food, delivery of oxygen and nutrients to cells and removal of waste products. It also cushions the joints, plumps up the skin and regulates body temperature.

Your body contains 40 to 50 quarts of water, and you lose an average of two quarts per day through respiration, perspiration and urination. If you don’t replace these losses, your health will suffer.

Severe dehydration is a well-recognized medical crisis. Brought on most often by prolonged bouts of diarrhea, vomiting or intense heat-related exercise, it can cause electrolyte imbalances, kidney failure, seizures and even death.

Mild dehydration, or hypohydration, however, has symptoms that are much more subtle, and it’s the last thing most physicians would consider as an underlying cause of ill health. But any degree of dehydration throws your body into rationing mode. To ensure survival, water is doled out sparingly, leaving organs and tissues to deal with the consequences.

Dehydration increases risk of urinary tract woes

When you don’t drink enough water, your urine becomes concentrated, making it easier for calcium and other minerals to precipitate out and create crystals. Over time, these crystals may form into small hard masses (kidney stones) that are excruciatingly painful when passed out of the body.

Urinary tract infections (UTIs) can also be staved off with adequate hydration. Most of these infections are caused when Escherichia coli (E. coli) make their way into the urinary tract. Drinking lots of water increases urination and flushes these bacteria out of the bladder and urethra. Upping your water intake to eight ounces per hour is actually a recommended treatment for UTIs.

Drench digestive disorders

Constipation responds well to increased water intake. As food moves through the digestive tract, water is absorbed by the colon. When too much water is removed, stools become dry and hard.

Fiber is helpful for constipation because it hangs onto water and keeps the stool soft and bulky. You can eat bran by the bucketful, however, and you’re still going to have problems if you’re dehydrated.

Water also induces gallbladder emptying, which helps prevent the formation of gallstones. Some people swear a glass of water also relieves heartburn, and it can decrease acid levels in the stomach. Be aware, however, that water on an empty stomach increases symptoms of heartburn in some people. If you’re one of them, you’re better off drinking it with meals.

The cardiovascular connection

Mild dehydration increases the risk of numerous cardiovascular disorders, including stroke and venous thrombosis. Water’s effects on hypertension (high blood pressure), however, are the best studied. When the brain senses that water supplies are low, it prompts the release of vasopressin, the antidiuretic hormone. Vasopressin signals the kidneys to conserve, or reabsorb, more water and the arteries to constrict – a classic recipe for high blood pressure.

Taking drugs to lower blood pressure may make matters worse. The first-line therapy for hypertension is diuretics, so-called “water pills.” Diuretics lower blood pressure by prompting the kidneys to get rid of sodium and water.

In other words, these drugs make you urinate more. But this can lead to dehydration as well as losses of water-soluble nutrients. To compensate, drink more water and take a good multivitamin and mineral supplement.

Dementia or dehydration?

Chronic mild dehydration increases as we get older, thanks to changes in water-regulating hormones and declines in kidney function. In addition, our sense of thirst becomes less acute – we just don’t notice that we’re thirsty.

Short periods of water restriction have been shown to impair alertness and ability to concentrate in people of all ages. I’m not saying that drinking more water is going to make anyone mentally sharper. Mild to moderate dehydration, however, appears to exacerbate cognitive dysfunction in older people, and some experts believe it may be a risk factor for more serious dementia and Alzheimer’s disease. Residents of assisted care facilities and individuals with cognitive impairment or poor mobility are at greatest risk.

From asthma to weight loss

Beefing up your water intake has also been shown to:

  • Reduce exercise-induced asthma
  • Improve joint and back pain by hydrating the cartilage
  • Prevent dental problems by ensuring adequate saliva production
  • Reduce post-exercise muscle soreness by flushing out toxins
  • Keep the skin firm by toning up collagen.

Drinking more water even appears to help with weight loss by suppressing appetite, burning a few calories and preventing water retention.

For optimal health, drink 10 to 12 glasses of filtered water per day and more if you’re exercising heavily or live in a hot or humid climate. I also recommend taking a good multivitamin and mineral supplement to replace the water-soluble nutrients you’ll lose in the urine as you drink more water.

Caution: If you have heart failure, end-stage kidney failure or other serious conditions, talk to your doctor before increasing your water intake.

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