Diets heavy on foods that are high in protein and low in carbohydrates can increase the risk of kidney stones and reduce the body's ability to absorb calcium after just six weeks.

These findings from a new study come at a time when an increasing number of Americans, seduced by anecdotal accounts of fast weight loss, are turning to low carbohydrate, high protein diets. Popularised by Dr Robert Atkins, these diets are having a revival after a recent cover story in the New …