Eminent biologist Leonard Hayflick died on August 1, 2024. He was best known for his pioneering research on telomers that determined a limit on human lifespan of approximately 120 years called The Hayflick Limit. Yet, in a recorded interview he told me that he never proposed such a limit and had never uttered the phrase The Hayflick Limit.

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Eminent biomedical researcher Leonard Hayflick died on August 1, 2024, at age 96. He was best known for his pioneering research on telomers, the piece of DNA that diminishes when normal cells replicate. He determined that the telomere disappears after about 50 replications of normal human embryonic cells, resulting in cell senescence and death. Fifty replications occur over a maximum of about 120 years This phenomenon came to be known as the Hayflick Limit for the human lifespan.

Hayflick was an outlier who relentlessly criticized aging research for emphasizing treating and curing diseases while investing little in basic molecular and cellular research. He insisted that common factors at the molecular and cellular levels underlying diseases associated with aging could provide answers leading to the cure of all age-related diseases including Alzheimer's.

In 2016 I interviewed Hayflick for an article titled On the Verge of Immortality or Are We Stuck with Death? He passionately exclaimed "Why in the hell aren't we studying the fundamental biology of aging if that is the major risk factor for age-associated diseases? Why are we ignoring it almost 100 percent?"

When I praised him for his discovery of the Hayflick limit he fired back, "I never said that." I was stunned. By then the Hayflick Limit was well-known in scientific circles. Was its creator denying it now?

After gathering my thoughts, I asked him why there isn't a Hayflick Limit since the telomere vanishes after 50 replications. Doesn't that imply a limit to the human lifespan? Almost every researcher proposing to extend the human lifespan begins with the question: Is it possible to exceed The Hayflick Limit? Microsoft Edge currently lists nearly 300,000 references for The Hayflick Limit.

Here is the transcript of my recorded interview with Leonard Hayflick on his denial of a Hayflick Limit:

Starr: There are hundreds as you well know maybe more articles about you that talk about the Hayflick Limit setting longevity at about 120 years.

Hayflick: No, That's absolutely spurious. I've never seen that in print before. If it has occurred it has occurred maybe once or twice but it's absolutely wrong.

Starr: Oh no, it's in hundreds of articles.

Hayflick: Hundreds of articles are wrong which is not unusual. In the past fifty years, I have never seen an article about my work that was accurate. If this is included in hundreds of articles it's dead wrong.

Starr: OK. If it's wrong it's wrong. You have the last word in this.

Hayflick: It has to be corrected. It did not set human longevity at approximately 120 years. I would like to see the data that supports that phrase. Give me one example.

Starr: When I submit this [article] to an editor and it says the Hayflick Limit based on the 50 replications of cells the question the editor will ask, "Then what's the limit?"

Hayflick: That editor needs to be educated in biology That's my response. It's a stupid editor who wants to hype the article and I'm unwilling to hype my work.

Starr: The editor would say if we are going to talk about life span, life expectancy, and there's a limit, what limit are we talking about"what are the parameters?

Hayflick: This is what I wrote in my article [original article]. The Hayflick-- I didn't use the word Hayflick Limit. It didn't exist at the time. I said the limit suggests the cellular basis for aging. That's what I wrote. Now I will say something to explain that. For a hundred years at least, prior to my discovery, it was believed that aging was caused by extra, in other words outside of the cell-- events like radiation, stress, and other agents that are outside the cell. My discovery changed the focus of research from those extracellular alleged causes of aging to intracellular causes. And that's what that work did. It did not set a limit on the human lifespan. In fact, I didn't even mention human longevity in that article.

Starr: An editor asks what is the limit? What does limit mean?

Hayflick: I just explained it. The limit means that the new explanation for aging can be found intracellularly and not extracellularly. And that was a humongous change in direction.

Starr: Indeed then, you have been misquoted in untold numbers of articles.

Hayflick: A million times

Starr: I'm looking at one article right now titled Can a Human Being Live Longer than 120 Years? It's called the Hayflick Limit and it goes on to sa"y

Hayflick: Did I write it?

Starr: No

Hayflick: These are people who want to hype their articles. It's not unusual for a misquotation or a misunderstanding to be made by someone let's say a week or two or a month after a publication and then have that repeated for the next fifty years. It's not unusual because people don't go back to the original work. Go back to my original paper and read it. You'll get it all.

Starr: The only thing that can be said then [about The Hayflick Limit] is that based on the 50 replications of cells or fetal cells, many researchers have interpreted this to mean [120-year lifespan]-so that they are saying it, not you

Hayflick: You can do that if you want because it's true but it's wrong.

After the interview, I wondered: Where does this leave us with the question of the human lifespan? Perhaps Leonard Hayflick has the last word. He told me earlier that "we know zero" about why cells age. When we unravel that mystery, he said, we will know the limit or potential for the human lifespan.

Authors Bio:

Bernard Starr has written about climate change since 2007 often calling for a program modeled after the Manhattan Project. He is a psychologist and Professor Emeritus at CUNY, Brooklyn College where he taught developmental psychology to prospective teachers and research methods and statistics in a graduate program that he directed. He is also the lead author of a lifespan textbook-- Human Development and Behavior: Psychology in Nursing. Starr is the founder and for twenty-five years the managing editor of the cutting edge Annual Review of Gerontology and Geriatrics published by Springer; also was editor of the Springer Publishing Co. series Adulthood and Aging and Lifestyle and Issues in Aging. For several years he wrote for the Scripps Howard News Service on healthcare, the boomers, and issues of an aging society. And for seven years he was writer, producer, and host of an award-winning radio commentary, The Longevity Report, on WEVD-AM Radio in NYC. His book, The Starr-Weiner Report On Sex and Sexuality in the Mature years (co-authored with Dr. Marcella Bakur Weiner) provided the first comprehensive data on sexual activity after age 60. He is a past president of the Brooklyn Psychological Association and a past president of the Association for Spirituality and Psychotherapy. He is also the main United Nations representative for the Institute of Global Education (IGE), an NGO with ECOSOC status. His latest book, The Crucifixion of Truth, is a drama about historical antisemitism set in 16th- century Italy and Spain. He also authored Jesus, Jews, and Anti-Semitism in Art. and Jesus Uncensored: Restoring the Authentic Jew. His earlier book, Escape Your Own Prison: Why We Need Spirituality and Psychology to be Truly Free, published by Rowman and Littlefield, explores spirituality as a psychology of consciousness. Currently, his articles are published at OpEdNews. Previously, he published on the Huffington Post contributor platform. Starr has also published in Salon, Barons Financial Magazine, the Algemeiner, and the New York Daily News.