On average people with longer telomeres live longer than people with shorter telomeres, even controlling for smoking, blood pressure, cholesterol level, BMI, age, and gender (Rode, 2015).  Short telomeres correlate with early death, hypertension, cardiovascular disease, cancer, chronic infection, diabetes (reviewed in Weischer, 2014), Alzheimer’s disease (Thomas, 2008), and risk of post-stroke dementia (Martin-Ruiz, 2006). In human twin pairs, the twin with the shorter telomeres is more likely to die first (Kimura, 2008). 

Telomere extension in old normal mice improves multiple aspects of aging, including neurological function, strength, insulin levels, and IGF-1 levels, and extends lifespan by 24% (Jaskelioff, 2011; Bernardes de Jesus, 2012).  Telomere extension rescues animal models of disease including liver disease and pulmonary fibrosis (Rudolph, 2000; Povedano, 2018). 

Because of the abundant evidence that short telomeres are unhealthy or fatal, and that telomere extension improves health and reverses symptoms of aging, therapeutic telomere extension has been advocated since the last century.  

It has been known for over 35 years that the enzyme telomerase extends telomeres.  But it was only in 2013 and 2019 that inventions at Stanford University enabled safe, rapid telomere extension by delivery of mRNA (Ramunas, 2015).