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Mechanism

Telomeres

Also: telomere
Last scientific update: jun 2026

Telomeres are the protective ends of your chromosomes, like caps on your DNA. They shorten with aging, but the link with health is more complicated than often thought.

Telomeres at a glance

WhatProtective caps on your DNA
Worth measuringLimited useModerate
LengtheningNot proven safeModerate
What countsBroad lifestyle

Telomeres are real, but having them measured or deliberately lengthened delivers little in practice.

29 studies4 answersupdated jun 2026
Evidence per claim
Measuring telomeres has limited use
View evidence →
Moderate
You cannot reliably and safely lengthen them
View evidence →
Moderate
Lifestyle influences your biological age more broadly
View evidence →
Moderate
Overweight speeds up aging
View evidence →
Moderate
Practical use

For whom

People curious about the biology of aging.

Not for whom

An expensive telomere test is wasted money for most.

Usual dose

Invest in proven lifestyle (exercise, not smoking, healthy weight) rather than telomere tests.

Key caveats

Telomere length fluctuates and is hard to measure reliably; single results say little.

What we know, and don't

Known

Telomeres shorten with age
Lifestyle influences aging more broadly
Not smoking and a healthy weight help

Not yet

Whether you can deliberately lengthen them
What a measurement means for you personally
Whether longer telomeres are always better
Common misconceptions
"Longer telomeres always mean healthier."
Incomplete. The link is complex; very long telomeres also carry risk.Moderate evidence
"A telomere test tells your biological age."
Not shown. Its usefulness for individuals is limited.Moderate evidence
How Telomeres connects
Data sources

· MeSH D016615

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