"The Benefits of Early Time-Restricted Eating"
Time-restricted feeding, where you try to squeeze the same amount of eating
into a narrow evening window, has benefits compared to eating
in the evening and earlier in the day,but also has adverse effects
because you’re eating so much so late.
The best of both worlds was demonstrated in 2018—
time-restricted feeding into a narrow window earlier in the day.
Individuals randomized to eat the same food, but just in an 8 a.m. to 3 p.m.
eating window, experienced a drop in blood pressures, oxidative stress,
and insulin resistance even when all the study subjects
were maintained at the same weight.
Same food, same weight, but with different results.
The drops in blood pressures were extraordinary,
from 123/82 down to 112/72
in five weeks, comparable to the effectiveness
of potent blood pressure drugs.
The longest study to date on time- restricted feeding only lasted 16 weeks,
a pilot study with no control group that only involved eight people,
but the results are still worth noting.
Overweight individuals who, like most of us,
were eating more than 14 hours a day were instructed to stick to
a consistent 10 to 12 hour feeding window of their own choosing.
On average they were able to successfully reduce their daily eating duration
by about 4.5 hours, and within 16 weeks they had lost seven pounds.
They also reported feeling more energetic and sleeping better.
This may help explain why all participants voluntarily expressed their interest
in continuing the time- restricted feeding on their own
even after the study ended.
You don’t often see that after weight loss studies.
Even more remarkably, eight months later they retained their weight loss
and improved energy and sleep.
At the one-year point, maintained their boosted energy and sleep
and kept the weight off, all from one of the simplest of interventions:
Just telling people to stick to a consistent 10 to 12 hour
feeding window of their own choosing.
How did it work?
Even though they weren’t told to change nutrition quality or quantity,
they appeared to unintentionally eat hundreds of fewer calories a day.
With self-selected time frames you wouldn’t necessarily think
to expect circadian benefits, but because subjects were asked
to keep the eating window consistent throughout the week
“metabolic jetlag could be minimized.”
The thinking is that because people tend to start their days later
on weekends that’s disrupting their circadian rhythm,
and indeed it is like they flew a few time zones west
on Friday evening and flew back east on Monday morning;
so, some of the metabolic advantage may have been
due to maintaining a more regular eating schedule.
Early or mid-day time-restricted feeding may have other benefits as well.
Prolonged nightly fasting with reduced evening food intake
has been associated with lower levels of inflammation
and better blood sugar control, both of which might be expected
to lower the risk of diseases such as breast cancer.
So, data was collected on thousands of breast cancer survivors
to see if nightly fasting duration made a difference.
Those who couldn’t go more than 13 hours every night without eating
had a 36 percent higher risk of cancer recurrence.
These findings have led to the suggestion that efforts
to “avoid eating after 8 pm and fast for 13 hours or more overnight
may be a beneficial consideration for those patients
looking to decrease cancer risk and recurrence,”
though we’d need a randomized controlled trial to know for sure.
Early time-restricted feeding may even play a role in the health
of perhaps the longest living population in the world,
the Seventh-Day Adventist Blue Zone in California.
Slim, vegetarian, nut-eating, exercising, non-smoking Adventists
live about a decade longer than the general population.
Their greater life expectancy has been ascribed
to these healthy lifestyle behaviors, but there’s one lesser known
component that also may be playing a role.
Historically, eating two large meals a day, breakfast and lunch,
with a prolonged overnight fast was a part of Adventist teachings.
Today, only about 1 in 10 Adventists surveyed
were eating just two meals a day,
but most, over 60 percent, reported breakfast or lunch
was their largest meal of the day.
Though this has yet to be studied with respect to longevity,
frontloading one’s calories earlier in the day with a prolonged
nightly fast has been associated with significant weight loss over time,
leading the researchers to conclude that eating breakfast and lunch
five to six hours apart and making the overnight fast last 18 to 19 hours
may be a useful practical strategy for weight control.
The weight may be worth the wait.