A shortage of zinc, an essential mineral, could be connected to the risk of heart disease. Recent study results have shown that zinc deficiency can cause oxidative stress, and the heart muscle is particularly vulnerable to oxidative stress, also a factor increasing the risk of heart disease.
Zinc is naturally in some foods - oysters, red meat, poultry, beans, nuts, whole grains, dairy. The mineral plays a central role in multiple mechanisms of cellular metabolism, including catalytic activity of multiple enzymes, immune function, protein synthesis, wound healing, DNA synthesis, and cell division. Depending on age and a person’s sex, the Food and Nutrition Board at the Institute of the National Academies recommends a daily zinc intake between 2 and 8 milligrams.
A lack of zinc, in addition to causing the above mentioned problems with cellular metabolism, can cause oxidative stress, where the ratio of free radicals to antioxidants is tipped in the favor of the free radicals, which can cause damage to the cell. The heart muscle often experiences oxidative stress because it has a lower antioxidative capacity than other tissues.
Antioxidants of all types, as their name suggests, can disable free radicals, restoring the cell’s balance back to a healthy level. Scientists from the Technical University of Munich explored the potential of two antioxidants, glutathione and vitamin E, to relieve oxidative stress in the heart muscle to lower a person’s risk of heart disease, with vitamin E performing especially well at boosting the integrity of the cell membrane.
The study began with nutritional zinc-deprived piglets, and negative effects appeared almost immediately. "The body was no longer able to compensate for the resulting shortage of zinc, even though our tests only ran for a few days," said lead author Daniel Brugger.
Along with a decline in cellular zinc, the concentration of both glutathione and vitamin E in the heart muscle dwindled. Additionally, researchers saw enhanced activation of genes responsible for apoptosis, a process involving programmed cell death.
"After the first phase, during which a reduction in tissue zinc concentration was observed, the heart muscle intervened and increased the amount of zinc back to the basal (control) level,” Brugger explained. “However, this increase took place at the expense of the zinc content of other organs -- above all the liver, kidneys, and the pancreas."
Further studies must be done to confirm the connection between zinc deficiency and maladies of the heart muscle, but for now the impact of declining nutritional zinc levels speaks for itself. The present study was published in The Journal of Nutrition.