TORONTO - More than a century ago, Canadian physician William Osler prescribed diets low in sugar and fruits to prevent gout, an excruciatingly painful swelling of the joints that was known to mostly afflict middle-aged men overly fond of the drink and meat-rich meals.
Now research suggests Osler may have been prescient in thinking a sweet tooth also contributed to what's been dubbed "the disease of kings and the king of diseases." (Women also get gout, but far more rarely.)
A 12-year study of more than 46,000 midlife men has found that men who frequently consume sugar-loaded soft drinks, fruit juices or whole fruits are vastly more likely to develop gout than those who ingest far more modest amounts.
Gout, thought to have afflicted Henry VIII and diagnosed in Charles Darwin and Benjamin Franklin, is caused by an excess of the waste product uric acid.
Too much uric acid in the blood causes crystals to be deposited in the joints, which can lead to severe inflammation and often intense pain. Gout most often affects the big toe but can also occur in the ankle, knee, foot, hand, wrist or elbow.
Principal investigator Dr. Hyon Choi, a rheumatologist at the University of British Columbia, said study participants who consumed on average five servings of sweetened soft drinks per week had an 85 per cent higher risk of gout than those who drank less than one serving a month - or "less than a Coke per month."
"The reason that sugar-sweetened soda drinks increased the risk is because of the sugar part of that drink, which is fructose ... from high-concentrated corn syrup," Choi said from Vancouver.
However, consuming diet soft drinks containing no fructose did not raise gout risk, concluded the study published in Friday's issue of the British Medical Journal.
Choi and his fellow researcher, Dr. Gary Curhan of Harvard Medical School in Boston, also looked to see whether it was just fructose from corn syrup - or also fructose in fruit juices and whole fruits that bumped up the chance of gout.
"Actually the latter is what we found to be true," he said, noting that drinking large amounts of fruit juice or eating lots of "oranges, apples" cranked up the likelihood of getting the ailment by 80 per cent compared to those with low intake.
"The main determinant is the sugaryness, the sweetness of the fruit," he said.
More than 750 men in the study - all U.S. health professionals aged 40 or older when the research began - developed a red, swollen joint at some point during 12 years of followup.
The link to sweet drinks and fruits was independent of other risk factors for gout, such as body mass index, age, use of diuretics (water pills), high blood pressure, alcohol intake and a diet rich in red meat and seafood.
Dr. Gregory Choy, a rheumatologist at Sunnybrook Health Sciences Centre in Toronto, called the research "one of the best-done lifestyles studies on gout that has come out for a long time."
Choy, who is no relation to the B.C. researcher and was not involved in the study, said the fact the risk of gout rose as the amount of fructose ingested increased "lends strength that this is indeed a real finding rather than a fluke of statistics."
Steven McNair, president and CEO of the Arthritis Society, said such studies are important for developing a deeper understanding of prevention and treatment for gout, which affects up to 500,000 Canadians, four times more men than women.
"It is important that people diagnosed with gout follow the treatment advice surrounding diet, exercise and medications as prescribed by their physicians," McNair said by e-mail.
Choi of UBC advises that anyone with a family history of gout or who has previously had it or is currently being treated for the condition should cut out fructose-laden soft drinks from their diet or switch to sugar-free pops.
"But in terms of fruit, that's difficult to just make one single recommendation like we can do with sugar-sweetened soda because of those known benefits for other major disorders such as lowering blood pressure, heart disease, stroke and certain types of cancer."
"If you have a bad, terrible gout, maybe you have to limit sweet fruits," he said.
As for the effects of desserts and other toothsome treats, Choy of Sunnybrook said previous small studies suggest that patients with gout who adopt a low-caloric, diabetic diet "do much better" than those who stick to their usual fare.
Eating a low-cal diet - including one that avoids too much sugar in whatever its form - also helps prevent obesity, Type 2 diabetes and cardiovascular disease that can lead to heart attack or stroke, he said.
"This should be looked at as a bigger picture," Choy said. "So less simple sugary drinks, be it in soft drinks or otherwise, would help."
