The mineral zinc is important for the heart and for survival in heart failure patients
The mineral zinc is essential for transferring energy for use by the heart and the heart is a very high energy muscle pumping one-million times every ten days. Zinc also reduces inflammation in the heart and functions as a powerful antioxidant. When the heart pumps out oxygen rich blood from its left lower chamber it is called the ejection fraction. The hearts ejection fraction is normally above 55% meaning the heart minimally pumps out at least 55% of the oxygen rich blood that fills this chamber every time it beats. In people with heart failure, the heart often has a reduced capacity to pump and the ejection fraction is below 40%. Because the heart is pumping less oxygen rich blood, people with heart failure have trouble exercising. They have shortness of breath and are fatigued and have trouble concentrating and this can occur even sitting still in people with advanced heart failure.
The capacity to exercise is a key factor linked to quality of life and even survival in these patients. In this study from the Department of Cardiovascular Medicine, Fukushima Medical University in Japan, 968 consecutively hospitalized patients with heart failure had their zinc levels measured and were split into three groups according to their level of the mineral. Heart function and exercise capacity was measured in each patient and then their health was followed by the doctors. The ability to exercise was similar between the groups but subjects in the group with the lowest zinc levels had a lowered capacity for using oxygen and peak oxygen consumption was significantly lower. Importantly survival was strongly connected to the level of zinc in the blood. The group with the lower zinc levels had a higher incidence of dying related to heart issues and even due to all cause mortality (any cause). The association between lowered zinc levels and predicting mortality was consistent in all subgroups. The study is published in the Journal of Cardiac Failure.