Study: Heart cells develop into adulthood

U.S. government scientists say they’ve determined cells in the human heart continue to develop into adulthood, but then decrease rapidly.

Researchers at the Lawrence Livermore National Laboratory said they discovered that as humans age, the percentage of new heart cells decreases markedly. By age 25, renewal of heart cells gradually decrease from 1 percent, turning over annually at .45 percent by the age of 75. About 50 percent of the heart cells a human is born with will regenerate during a lifetime.

The study that included researchers from the Karolinska Institute and Lund University in Sweden and Claude Bernard University in France determined human heart cells, on average, are six years younger than the individual adult.

The research is detailed in the journal Science.