Dr. William Clark, in his office at LHSC's Victoria Hospital.
Too much of a good thing?
Walkerton study yields unexpected finding
You can never have too much of a good thing, or so the saying goes. In the case of fluids, such as drinking water, researchers have discovered that sometimes the opposite is true.
In a study published in January in the Canadian Medical Association Journal, Dr. William Clark, a scientist at Lawson Health Research Institute, a nephrologist at London Health Sciences Centre and Professor at the Schulich School of Medicine & Dentistry at The University of Western Ontario, found that excessive fluid intake can lead to proteinuria, or protein in the urine. Proteinuria is known for causing kidney failure and has also been associated with cardiovascular diseaseódamaging blood vessels, which can lead to heart failure or stroke.
Proteinuria is often a side effect for individuals suffering from kidney disease, diabetes mellitus, or hemolytic uremic syndrome, a blood-clotting disease. As part of a screening study to assess the long-term health outcomes in residents of Walkerton, Ontario following the water contamination outbreak in 2000, Dr. Clark and his team of Walkerton E.coli Long-Term (WEL) investigators came across some significant findings. One hundred adults were identified as having proteinuria and polyuria (frequent urination), but had no medical history or medication use to explain their condition. Of the 100 individuals, 56 were then instructed to reduce their daily fluid intake to less than eight large glasses (two litres) per day for one week. Results showed that the proteinuria and polyuria were largely reversed. "These individuals were causing their condition from excessive water drinking," says Dr. Clark. "The treatment was simple. When the patients drank less water, we saw the condition go away."
"It is unknown at this time whether the reversible proteinuria associated with large fluid intake in these otherwise healthy people could affect their kidney function in the long term," said Dr. Clark. "Until such data is available from our longitudinal study, it may be advisable to discourage otherwise healthy people from consuming large volumes of fluid."