6 Tuesday May 24 2022 | the timeshealth
R
ussell Foster, the
University of Oxford
professor of circadian
neuroscience, is at a
double disadvantage
when we meet on
Zoom. First, he’s just
getting over Covid;
second, he’s one of nature’s night owls.
Our interview is first thing in the
morning — a time when he admits
to feeling sluggish.
That’s ironic for a man whose
mission is to get us all sleeping, eating,
exercising and taking our meds in
sync with our natural daily cycles.
If we get all this right, Foster promises,
we can enjoy longer, happier and more
fulfilling lives. Conversely, he warns, if
we persist in modern habits that clash
with our body clocks, our risks soar for
cancer, obesity, type 2 diabetes, serious
infections and mental illness.
This makes Foster sound like
a harbinger of doom, but he’s the
opposite: the man whose Ted Talk,
Why do we sleep?, has amassed
8.5 million views and is ranked
among the most popular science
lectures on the platform is jovial,
friendly, even boisterous, despite
his Covid cough and the early
hour. Nevertheless he’s passionate
about society’s flagrant disregard
for our bodies’ and brains’
chronological needs.
“The arrogance of being human
means that we feel we are free from
the constraints of billions of years
of evolution,” he says. “We try to
squeeze more and more into the
day and things fall apart.”
Britain’s sleep crisis made headlines
last week with the news that nearly
one million patients with insomnia
will be prescribed a £45 self-help app
instead of sleeping pills on the NHS.
GPs have been told to offer Sleepio,
a six-week digital therapy programme,
as the first-line treatment.
Foster is clearly a fan. He’s quick to
announce a professional interest — he
recruited Sleepio’s principal developer,
professor Colin Espie, as an Oxford
colleague. Nevertheless, he says that
behaviour-modification, rather than
sleeping pills, is the way forward for
insomnia treatment.
“The app is a ‘best of’ the available
therapy techniques for insomnia,” he
explains. “One of its advantages is that
it’s been properly scientifically tested,
with studies that cover thousands
of people and were published inHow to reset
your body clock
for better health
Your midlife sleep won’t be the same as it was in your
twenties — but you can still improve it, Russell Foster,
an Oxford professor of neuroscience, tells John Naish
Professor Russell Fosterreputable peer-reviewed journals. You
see other claims made for insomnia
approaches that only involved testing
it on 12 undergraduates for a few days,
which is jaw-droppingly inadequate.”
There will still be a place for
sleeping pills, however. Foster says:
“They can be useful as a short-term
corrective. Over time the effects
become less satisfactory and they
can cause dependency.”
While an app may prove a boon
for individuals, we are still left with
the problem of our insomnia-inducing
modern culture. We live at the sharp
edge of the 21st century, plugged into
a global culture that never sleeps. But
nevertheless, we remain cave-born
creatures who are slaves to the
circadian rhythm. As Foster explains
in his new book Life Time, we have
biological clocks within the cells of
our liver, muscles, pancreas, fat tissues
and probably every organ and tissue
of the body, all kept in sync by a
master clock in the brain.
Our most obvious circadian
rhythm is the sleep-wake cycle,
itself regulated by a genetic make-
up that determines whether we
are morning larks or night owls.
Larks seem to have faster body
clocks due to changes in one or
more of their clock genes, Foster
explains. Owls’ clocks run more
slowly. But, he adds, these basic
predispositions often change as we
get into midlife. “I have de-owled
over the years, though I’m still not a
morning type,” he says. “At 62 I’m no
longer an up-till-2am type. Bedtime is
more like 11pm to midnight.”
But anyway, why feel guilty about
being a first-thing slug-a-bed? “There’s
a strange machismo about being busy
early in the morning,” Foster argues.
“Basically the attitude is about the
marginalisation of sleep. We rob
sleep at our peril.”
Margaret Thatcher, who declared
that “sleep is for wimps” and boasted
of sleeping only four hours a night,
may be a tragic example of the perils
of fighting our body clocks in the
name of industriousness. She died
aged 87 in 2013 with dementia,
although Ken Clarke, her cabinet
colleague, says she already showed
serious signs of the brain disease in
her last year in office, aged 64, in 1990.
Newly emerging research shows
how lack of sleep lets toxic brain
cell-killing substances build up in our
brains, Foster says. During healthysleep our cerebral spinal fluid clears
away proteins called amyloid beta
and tau, which are Alzheimer’s toxins,
as scientists at Pennsylvania State
University reported in the journal
PLOS Biology last year.
“That’s just one of the reasons
why I always defend my sleep quite
seriously,” Foster says. “I’m making
sure that I am getting the sleep that
I need. I finish in the evenings at 7pm
and wind down with the family —
wife, son and daughter — and have
a reasonable amount of sleep. For meseven to eight hours is good.” Our
bodies’ need for chronological
correctness does not stop at sleep.
Hour by hour our bodies’ health needs
change, Foster says.
“What we do when really matters.
Numerous studies have shown that in
midlife you have a 50 per cent greater
chance of a stroke between the hours
of 6am and noon. In the morning
there is a circadian-driven sharp rise
in blood pressure in anticipation of
getting up and starting the day, getting
your metabolism moving beforehand.
There is also an increase in
blood-platelet stickiness as a result ofyour immune defences firing up to
protect you during the day.”
This can make a huge difference in
when we take common medications,
he explains. “If you are on anti-
hypertensive drugs, you should take
them last thing at night because their
effects are long-lasting and will protect
you when waking. If you’re taking
aspirin to stop your blood getting
sticky, however, take it first thing in
the morning rather than at night [as]
aspirin doesn’t last long in the body.”
Different drugs can have their
best effects at different times of day,
he adds. “Some cancer drugs, for
example, work best when given in
the late afternoon or early evening.
But in busy hospitals drugs are often
given only when staff find the time.
Furthermore, many trials don’t
actually test what time of day
medications are most effective. This
may be a serious problem because
better timing could markedly improve
patient survival rates.”
So much for meds. With sleep
we are all different and no single
prescription will ever work, Foster
says. “I get sick of seeing the sergeant-
majors of sleep shouting that we all
must do this or must do that. Your
sleep biology can be likened to your
shoe size: one size does not fit all.
Making us all wear the same shoe size
would be not only foolish but
potentially harmful.
“There are lots of ways to get good
sleep — not just the one pattern of
eight hours’ uninterrupted slumber. In
midlife there’s no point harking back
to the sleep you had in your twenties
and thirties as some kind of ideal. It’smof the b
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Life Time: The New
Science of the Body
Clock, and How It Can
Revolutionize Your
Sleep and Health
by Russell Foster is
published by Penguin
Life on May 19, £16.9920
The maximum number of
minutes a nap should be.
Any longer and you’re
probably not getting
enough sleep at night