The Hayflick limit is a concept in biogerontology that a human cell culture in vitro will only divide 48-50 times, on average. It is named after Dr. Leonard Hayflick. The Hayflick limit (or Hayflick phenomenon) is the number of times a normal human cell population will divide until cell division stops. Empirical evidence shows that the telomeres associated with each cell's DNA will get slightly shorter with each new cell division until they shorten to a critical length.