Kidney stone warning on high-protein diet

CONVERTS to the Atkins diet have a higher risk of developing kidney stones, doctors have claimed.

They say the fashionable high-protein, low-carbohydrate regime has led to a sharp rise in the condition, with the soaring number of young women patients a particular concern.

Dr Bill Robertson, a clinical biochemist at the University College Medical School of London, claims the diet could double the risk of kidney stones.

He says research shows that a diet rich in animal proteins and calcium oxalate constitutes a "double whammy as far as the threat of developing kidney stones goes".

Kidney stones - hard deposits in the kidney - are extremely painful. An operation or laser treatment is often needed to remove them.

Dr Robertson added: "It is the worst possible combination. The absence of fruit and other vegetables means the body is deprived of a means of counteracting the negative effect. The high-protein diets have contributed to an increase in the number of kidney stones that we are seeing. There is no doubt the diet is good for losing weight, but you have to think about the secondary effects."

One woman in every 2.5 men is affected by kidney stones, but this ratio has risen recently to one woman in every 1.3 men.

The increase mirrors the changes in sexual behaviour among young women. Because women are having sex younger and more frequently than in the past, they are more susceptible to urinary tract infections, such as cystitis, which can be brought on by sexual contact.

The antibiotics that are commonly prescribed to treat those infections deplete the body of the organism that normally insulates them against the development of kidney stones. As women are more likely than men to try to lose weight by dieting, their chances of developing kidney stones have soared.

The phenomenal success of the Atkins diet was revealed last week with news that books written by the late doctor are outselling everything but Harry Potter by three to one.

Since it was published in 1999, Dr Atkins’ New Diet Revolution has sold 1.1 million copies in Britain and Ireland, with the updated paperback edition selling a current average of just over 150,000 a month.

Dr Atkins first published his diet more than 30 years ago but it has only recently become a phenomenon, endorsed by converts as diverse as Senator Al Gore, the actresses Renee Zellweger and Catherine Zeta Jones, and Geri Halliwell, the former Spice Girl. When Dr Atkins died from head injuries in April after slipping on ice, his book had sold more than ten million copies.

Until now, any evidence of the negative health effects of the Atkins diet has been negligible. One unconfirmed theory suggests an Atkins-style diet might worsen osteoporosis. Otherwise, the diet’s known side-effects are more socially problematic than health-threatening - but constipation and bad breath caused by the process of ketosis (when fat is broken down by the body) is a small price to pay to drop a dress size, say Atkins disciples.