The Study was conducted by the Sloan Center on Aging & Work at Boston College between November 2007 and September 2008 (Time 1: November 2007 to March 2008; Time 2: May 2008 to September 2008). The Center collaborated with 9 U.S. workplaces (12 departments) on this study.
Heart muscle cells can take approximately 20 years to completely renew themselves. Never Cells that cannot repair â Itâs unfortunate for many, but old age can take itâs toll on the eyes and brain.
1 So you could say that on average, human beings replace all their fat cells about every ten years.  Cardiomyocyte heart cells are replaced at a reducing rate as we age. At age 25, about 1% of cells are replaced every year. Replacement slows gradually to about 0.5% at age 70.