WASHINGTON (Reuters) - Heart conditions became worse in male mice carrying a genetic mutation for heart disease when they were fed a soy diet, a study published on Wednesday showed.

Male mice carrying the mutation for hypertrophic cardiomyopathy or HCM, were severely affected by the soy diet, showing enlarged heart muscles and eventual heart failure, according to the University of Colorado at Boulder study published in the Journal of Clinical Investigation.

HCM is the leading cause of death in young athletes and affects about one in 500 people. Eighteen genes associated with the disease have been identified, according to University of Colorado professor Leslie Leinwand.

Soy foods and diet supplements are perceived to be a huge health benefit to humans. Consumers spent an estimated $4.7 billion on them in 2005.