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Getting more sleep doesn’t just help you wake up refreshed in the morning.
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It can also literally keep you young.
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New studies show that those who are under stress and don’t get enough shuteye could
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age up to six times faster than they would otherwise, giving a whole new meaning to the
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term beauty rest.
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It all comes down to a part of our genetic toolkit called our telomeres.
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See, we’re made up of approximately 30-40 trillion cells of human tissue, and the DNA
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for each of those cells is tightly coiled up into chromosomes, which are housed in the
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nucleus of each cell.
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While we’re just living our lives, going about our business, our cells are replicating
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all the time.
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Every time a cell divides, the chromosomes have to be copied as one cell splits into
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two during mitosis.
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And during that cell replication process, telomeres act as protective caps on the ends
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of our chromosomes.
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Like, if our chromosomes are shoelaces, then telomeres are the little plastic tips on the
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ends of those shoelaces that keep them from fraying away.
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In most living things, including us, telomeres are made of hundreds to thousands of repetitions
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of the simple nucleic acid sequence TTAGGG.
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This cap does a lot of things, including telling our cellular machinery where one chromosome
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ends and another begins.
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They also serve as a buffer during the copying process, because cell replication isn’t
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perfect.
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The little tool that does the DNA copying isn’t as precise as you might hope, and
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can’t properly replicate the very ends of the chromosomes—this can cause a lot of
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issues, and is called the end replication problem.
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To avoid that chop-chop happening to your actual DNA—y’know the important stuff
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that tells your cells what to do—your telomeres take the hit instead and every time a cell
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divides, a little chunk of the telomere is lost in the process.
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So telomeres shorten with each cell division, but they also get shorter as you age.
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Like, even when you’re producing new cells, your telomeres are now shorter than they once
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were when you were younger, a trend called ‘telomere attrition’.
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This means that your chromosomes are less protected from damage during cell replication.
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Which is what scientists believe could be behind the decreased function and wellness
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of our bodies as we age, and could lead to degenerative diseases like Alzheimer’s.
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This info may now have you wondering, ‘well jeez, Louise, what do I have to do to keep
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my telomeres from shortening as I age?'
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On a certain level, there may not be much you can do about it.
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Your telomeres’ length and how fast they shorten throughout your lifetime is highly
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variable.
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Estimates say anywhere from 30-80% of your telomere’s characteristics could be due
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to genetic factors and other things out of your control like your father’s age at the
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time you were conceived.
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But, there’s good news: there are some things under our control.
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While telomeres are the protectors of our DNA, they are also very susceptible to damage
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themselves by—most notably—stress.
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Stress is an ambiguous word, but can come in a multitude of forms: smoking, obesity,
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exposure to trauma, a psychological disorder like major depression, and so much more, all
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of which can lead to physical effects like higher levels of stress hormones and the presence
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of inflammation.
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Which are associated with acceleration of telomere shortening.
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And as we’ve already established, telomere shortening is not good for your health.
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Just thinking about telomere shortening is stressing me out and probably shortening my
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telomeres!
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Man, I really need to get more sleep.
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Exercising, staying away from cigarettes, doing what you can to destress might actually
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add years to your life in the form of telomere length preservation.
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But saving your telomeres from excess shortening won’t necessarily save you from the things
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you’re genetically predisposed for.
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It just means they may happen to you later, rather than sooner.
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And aside from making good lifestyle choices, there may be something we can take advantage
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of to lengthen our telomeres built right into our cellular machinery.
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Telomerase is an enzyme that lengthens telomeres.
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In our adult stem cells, which is where new cells in our body come from, and our germ
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cells, which make sperm and eggs, telomerase is busy building those telomeres back up.
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If we could somehow get telomerase to build back the telomeres in our somatic cells, our
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regular body cells, that would be great!
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But the problem is that turning telomerase on is actually associated with cancer because,
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again, cells aren’t meant to just replicate forever and if they do, it can be a problem.
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These complex questions about telomere length and what we can do about it is a huge research
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field and we are just skimming the surface here, so let us know if there’s something
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in particular you’d like us to cover.
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All this telomere business has really important implications for our future in medicine and
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other kinds of innovation.
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Dolly the cloned sheep, for example, was born with shortened telomeres and actually died
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prematurely, telling us we’ll need to take telomere science into consideration when working
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on extremely ambitious synthetic organisms.
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Scott Kelly, the astronaut who spent a year aboard the International Space Station, experienced
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significant telomere shortening due to the stress his body was exposed to in space.
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And now you have some serious scientific backing when saying that taking some chill time is
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good for your health.
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Fun Fact: Telomeres are made of the same amino acid sequence in almost every prokaryote,
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meaning they are HIGHLY conserved.
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Your telomeres are the same as a protists, as a sloths, as a ladybugs.
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That’s pretty cool.
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Wanna know more about what happened to Scott Kelly’s DNA during his year in space?
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Check out this video here and make sure to subscribe for more genetic deep-dives.
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Thanks for watching.
