Based on an analysis of toenails, a team of Dutch researchers said they believe people with low levels of selenium in their bodies may be at greater risk of sudden heart attack. Writing in the Journal of the American Medical Assn., the seven researchers said they compared 84 healthy "controls"--people who had never had heart attacks--with 84 patients brought to the Zuiderziekenhuis Hospital in Rotterdam after having sudden first attacks.
The heart attack patients had significantly lower levels of selenium in their red blood cells and toenails than did the control group. Overall, people whose toenail selenium levels were in the bottom 25% were 4 1/2 times more likely to suffer a sudden heart attack as people whose selenium was in the top 25%.
Toenail measurements of selenium are especially useful because they reflect patients' longer-term selenium status--how much selenium was in their bodies as much as a year before they had their heart attacks, the scientists wrote.
Led by Frans J. Kok of Erasmus University Medical School in Rotterdam, the researchers speculated that selenium may boost an enzyme in the body that protects it from free radicals--rogue oxygen and other molecules that may harden of the arteries and damage heart cells.