A review of research on the effect reducing salt consumption has on heart disease produced inconclusive results, the authors of a U.S. journal article said. The study published in the American Journal of Hypertension said there was no strong evidence that cutting back on salt prevented death from cardiovascular disease. The Cochrane Collaboration review of published literature, in fact, found only seven randomized controlled studies. Together, the data did not show any significant influence from sodium on mortality rates, said author Rod Taylor of the University of Exeter in Britain. Since cutting down on salt has become routine medical advice, Taylor and his colleagues recommended further large-scale, long-term studies of the effect sodium has on the cardiovascular system.