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Travel can be tough, the sun sets at the wrong time, rises too early or too late and no matter
how much mental power you put toward the solution -- it always seems like a fight against yourself.
What if a simple DNA tweak made jet lag a memory forever...
I fly a lot for this job. In the first few weeks of 2015, I was in five different time
zones, two countries and who knows how many hours of sleep were lost… Zipping from timezone
to timezone makes us feel awful but why?! Desynchronosis.
Desynchronosis is when your internal circadian rhythm -- your biological clock -- gets out
of sync with the clock out here in the world. Every day, your body has controlled and regular
releases of proteins, sugars, hormones -- all based on your internal circadian rhythm. When
that cycle gets out of sync, the cyclical upheaval affects hunger cycles, eating habits,
bowel habits, and (of course) sleep patterns. Symptoms include headaches, drowsiness, lethargy,
irritability, mild depression, attention deficit, disorientation and even diarrhea or constipation!
Researchers have found the dry airplane environment, changes in pressure and the time-difference
on arrival may all affect the condition, but the biggest problem is sunlight. As you know
if you've watched DNews regularly, the hormone melatonin keeps your sleep-wake cycle in sync
which drives your circadian rhythm. The suprachiasmatic nucleus -- in the hypothalamus -- cuts melatonin
production when there's more light and amps it up when there is less. The further afield
you go, the more out-of-sync your body is with the regular day-night cycle; so when
sunlight hits your retina at the wrong time, your body gets all messed up and you experience
desynchronosis; this is especially true when going East, as the day gets longer.
But, a study in mice from a 2013 issue of Cell, looked at the connections from the retina
to the SCN and how a chemical called Sik1 acted as a chemical snooze button, telling
the SCN to stop preparing the body to change the sleep-wake cycle! Unfortunately, they
didn't know quite how to use it, just that it was involved.
And now, a new study in eLife found jet lag might be cured by tweaking the single gene
that controls that sleep-wake cycle. While doing research on dementia, researchers at
the Salk Institute for Biological Studies found there were 213 genes which controlled
the suprachiasmatic nucleus, one of those, LHX1, is coded just for light sensing! Those
mice without LHX1 recovered from an 8 hour jet lag much more quickly than those without
it! There were side effects, though. The mice they tested couldn't live like that forever,
their neurons weren't as in-sync as the normal mice. Plus, there was a decrease of an intestinal
peptide called Vip, which no one knew was related to the SCN. Vip affects cell communication…
so from there scientists think we should go on to research Vip -- because perhaps by breaking
it down more quickly, we could rapidly get over jet lag.
The best way to get over it, without messing with our genes, is a matter of debate. Intriguingly,
a small double-blind study by the British Medical Journal, found taking melatonin had
pretty much no more effect than a placebo; but another study found it was quote "remarkably
effective!" So, it might be something you should try. A study in Cell Reports found
insulin may help regulate the circadian rhythm! So, maybe, eating carbs could synchronize
the stomach clock more quickly than other foods, possibly pulling the rest of the body
clock with it.
For myself, I try to stay awake until a "normal" bed time -- say 10pm, and then wake up at
a "normal" wake up time -- 8 or 9. By doing so, the clock internally is forced into the
new time. It also helps to keeping lights dim before sleep and bright in the morning
-- both at home AND on the go… even NASA recommends doing this; as it helps continually
train your SCN to respond. Daylight is the best thing, according to The National Sleep
Foundation, because it quickly resets your SCN; while being indoors is the worrrst. They
also recommend waking up with an alarm, not oversleeping; and to avoid alcohol and caffeine,
because they'll further complicate your sleep-wake cycle.
In the end, desynchronosis is a brand new human condition; it's only existed for about
100 years, and it's about as first-world as problems can get. Most humans simply can't
travel far enough, fast enough, to experience it, but if you do; good night, and good luck.
Of course, jet lag only REALLY happens if you get into an airplane and fly somewhere.
Which has it's own set of problems. Ever wondered why airplane meals are always terrible? You
lose some sensing abilities in flight… but I won't spoil it. My buddy Julian explains
for you, (right here) What's the worst
jet lag you've ever experienced? Tell us how you dealt with it.
