Sun, heat, dehydration and kidney stones

Kidney stones occur more commonly in the summer, so stay hydrated to avoid one of the most painful conditions there is.

Well, with the heat wave we’ve been enjoying over the past week, I’ve found myself pondering how to stay comfortably cool, keep the apartment cool enough to be able to sleep, get my vitamin D dosage without burning to a crisp, and focusing on staying hydrated enough.

Dehydration creates a number of problems in the body, including increasing blood pressure, accelerating osteoarthritis (the wearing down of joints), and increasing the risk of kidney stones.

Kidney stones tend to develop more frequently in the summer months, and as anyone that has had one will tell you they are something you don't want to get as they are excruciatingly painful.

The south-eastern States, hot for most of the year, are referred to as the “kidney stone belt”, and the Middle East has about double the rate of kidney stones than North America, mostly due to inadequate water intake which is especially needed in hot weather.

Staying well hydrated is fundamentally important to health, and most tend not to drink enough water even when the weather is cool. Because we sweat more when we are hot, we need even more water to replace what we are losing.

If you’ve suffered from kidney stones in the past you are at risk of getting them again, so staying well hydrated is a very important preventative measure, as water reduces the concentration of the minerals that might crystallize into stones.

One often hears the saying “drink plenty of fluids” when it is hot, but some fluids will make the body’s internal environment worse, making one more prone to kidney stones. Soda pop is a fluid that not only dehydrates making one more prone to kidney stones, but also contains phosphates, which is linked to higher kidney stone recurrence.

Dark soft drinks like coke, tend to contain oxalates, which further increase one's susceptibility to kidney stones. Any caffeinated beverage is dehydrating, so for every cup of a caffeinated beverage you drink, do drink another glass of filtered water.

Sugary drinks tend to mess with calcium and magnesium absorption, once again increasing one's risk for kidney stones. With kids drinking so much in the way of sugary drinks and soda pop now, children as young as 5 are being afflicted with kidney stones.

The healthy fluid of choice is water – add a twist of lemon or lime if that will help you drink enough of it.

How much water should one drink? According to Dr. Batmanghelidj who wrote the book Your Body's Many Cries For Water, take one's bodyweight in pounds, divide by two, and that is the number of ounces one should drink each day.

When it is hot, probably not a bad idea to drink a little more to make up for sweat losses. If you are exercising in the heat (not the best idea – exercise in the early morning or evening rather than during peak heat times) you may want to weigh yourself before your exercise and again afterwards, and replace the water weight lost during the exercise.

One can tell if one is well hydrated if the colour of the urine is clear to very light yellow. If your urine is bright yellow, drink up! (Some vitamin supplements will turn the urine an almost fluorescent yellow colour, which would make it impossible to judge hydration levels.)

There have been media reports about people dying from drinking too much water, usually during or after an athletic event. The problem is caused by diluting the electrolytes to the point they can't do their job.

So the water we drink needs to be adequately mineralized – add a pinch of Pascalite Clay or unrefined, air dried Celtic Sea Salt, to any water that has been distilled or filtered by reverse osmosis as all the minerals have been removed by these processes.

Drinking mineral-rich water will ensure that our electrolytes won't become too diluted.

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Related Tips:
How much water should we drink?
Osteoarthritis – is dehydration implicated?
Remineralize your water
Choosing a water filtration system

Batmanghelidj F. MD Your Body’s Many Cries for Water Global Health Solutions, Falls Church, VA, 2006.

University of Michigan Health System. Kidney Stones In Children On The Rise, Expert Says ScienceDaily 5 May 2009. 1 August 2009.

University of Michigan Health System. Stay Hydrated This Summer To Prevent Painful Kidney Stones. ScienceDaily 5 June 2007. 1 August 2009

Guerra A et al. Concentrated urine and diluted urine: the effects of citrate and magnesium on the crystallization of calcium oxalate induced in vitro by an oxalate load. Urol Res. 2006 Dec;34(6):359-64.

Guerra A et al. Effects of urine dilution on quantity, size and aggregation of calcium oxalate crystals induced in vitro by an oxalate load. Clin Chem Lab Med. 2005;43(6):585-9.

Rodgers A. Effect of cola consumption on urinary biochemical and physicochemical risk factors associated with calcium oxalate urolithiasis. Urol Res. 1999;27(1):77-81

Rodgers AL. Effect of mineral water containing calcium and magnesium on calcium oxalate urolithiasis risk factors. Urol Int.

Copyright 2009 Vreni Gurd

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  1. Harold Smage said,

    July 18, 2010 @ 9:18 am

    I am glad to see “mineral rich” water mentioned!

    Many of us that live in rural areas have the benefits of water containing natural ground minerals available to us from small town wells or private wells.

    How stupid of so many to not use this source of water and instead buy bottled water that is not in any way superior to what our tap provides!

    People are wasting money on bottled water.

    Resources are being squandered in the process of providing bottled water. The product is hauled across the country- placed on the shelves of stores to be sold and hauled home for consumption- using up resources on the way.

    Often times the product purchased is lower in desirable minerals than their own tap water!

    Some even buy and drink distilled water which can actually deplete the body’s mineral supply!

    it it is discouraging to see peoples carts in the food stores stacked with many packs of water. No doubt they grumble about the high cost of food!


  2. Robert said,

    July 19, 2010 @ 7:57 pm

    A very informative article. Kidney stones sound painful but I got a more painful experience from dehydration five years ago. I played in a game with minimal fluid intake hours before. After the game I found blood in my urine. Increasingly got worse and my kidney function fell to 30%. Dehydration caused an auto-immune reaction which made my immune system attack my kidneys. Doctor prescribed prednisone, the steroid that was prescribed heavily to SARS patients in Asia in 2003. Steroids almost drove me mad as I couldn’t sleep, overate, caused weak and stiff joints and massive bloating. After 4 months on the drug, my kidney function rose back up to 70% but that’s the most I’ll get from my kidneys for rest of my life. All because I failed to drink enough fluids before vigorous activity.

    Robert -Hong Kong

  3. Vreni said,

    July 20, 2010 @ 11:08 am

    WOW, that is quite a story. I’m so glad you shared it. Drink up, everyone!

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