All normal human somatic cells have a finite number of times. Cells are described as cellular senescent when the limit is reached during their division. Telomere shortening has been associated with cellular aging, which leads to body aging because of the lack of cellular functions. In activated T cells unlike most somatic cells, telomerase activity is up regulated, resulting in increased telomere length. Cycloastragenol and Astragaloside IV both claim to be telomerase activators and sold as nutritional supplements.