As if global warming weren't bad enough as it is, researchers now say that the extra amount of carbon dioxide in Earth's atmosphere will strike us in one of the most painful ways possible: kidney stones. And this time it's not selective and it's most certain that some of the leaders of the G8 states will feel head on at least one of the effects of global warming. Luckily, they agreed last week to cut even more of the carbon dioxide emissions in the coming years.

According to predictions, in the US alone, more than 2.3 million people will contract kidney stones every year in the next four decades, as a result of climate change.

"We're certain that climate change will continue and increase, and we're equally certain that increased temperatures will lead to increased kidney stone formation," says hydrologist Tom Brikowski of the University of Texas. Temperature increases cause dehydration and low urine volume, which inherently leads to calcium deposits forming in the kidneys.

Currently, about 20 percent of the population of the US has kidney stones, and the number is expected to double in a southern strip of the country dubbed by researchers the 'kidney stone belt'. Aside from this particular region, the number of patients suffering from this painful condition is very likely to increase in California, Texas, Florida and the north-eastern coast, although the South will still be the most affected.

This in turn translates into an additional 1.3 billion dollars a year spent on treating new patients. The study was restricted to the US, albeit similar effects could be observed all over the world.

"This may be an underestimate based on what we know. The predictions are based on mean annual temperature, and we know that the extremes, like heat waves, could play an even more severe role. Rather than everybody parking their Hummers - although they should - you can address this directly with fluid management," says Paul Epstein of the Harvard Medical School while pointing out that drinking more water would slow the kidney stones growth, although this should not divert the attention from the real problem of the world, global warming.