Although bottled water has become increasingly popular worldwide, few of these products have an optimal mineral profile. More than half (59%) of the commercial bottled water consumed worldwide is purified water, and the remaining 41% is primarily spring or natural mineral water [  ]. Meanwhile, there has been a rapid increase in the installation of seawater desalination facilities in water-stressed countries; post-treated desalinated water has a very low content of bicarbonate, calcium, and magnesium [  ]. Epidemiologic studies have documented an inverse relationship between the mineral content, or hardness, of water and cardiovascular disease (CVD) [ 3 , 4 ]; however, no experimental studies have assessed this issue to date. Therefore, we conducted an experimental investigation of the relationship between water hardness and CVD risk among both rabbits and young men.