famous study in 2000 compared the impact
of soda versus jelly beans that people
add 28 extra spoonfuls of sugar to their
daily diet in the form of jelly beans or
soda pop
then they measured how many calories
they ate over the rest of the day to see
if their bodies would compensate for all
that extra sugar
this is how many calories the jelly
beans group was eating before the study
started
but when eating handfuls of jelly beans
their bodies registered all those extra
calories so they ended up eating less of
everything else throughout the day so
even adding the jelly bean calories
they're eating pretty much the same
number of calories before and after
adding jelly beans to their diet
but in the soda group
this is how much they started eating
and despite all the added calories from
the cans of soda they were drinking
every day they
kept eating about the same amount
so with the soda calories added in
no wonder they gained weight after a
month of drinking soda their bodies
didn't seem to recognize the extra
calories when they were in liquid form
so didn't compensate for them by
reducing their appetite so they'd eat
less the rest of the day
this lack of regulation may be used to
advantage the researchers suggests
if you want to get fat
but what if you don't
if we drink a smoothie for breakfast
instead of a solid meal will our body
think we skipped breakfast and make us
so ravenous at lunch we eat more than we
normally would and end up gaining weight
okay well first is this solid versus
liquid calorie effect real
soda and jelly beans don't just differ
by physical form they have different
ingredients
that's a problem with a lot of these
kinds of studies they use dissimilar
foods
like this study comparing liquid to
solid breakfast
they either got
fruit juices and skim milk for breakfast
or oatmeal with blueberries and apples
in it and lo and behold study subjects
were less hungry after the oatmeal
duh
that may not be a solid versus liquid
effect those are completely different
foods
to test for a solid versus liquid effect
you'd have to use the exact same food in
just two different forms even this study
was flawed it purported to show that
eating apples before a meal is so good
at filling you up you eat fewer calories
overall but that pureed apples weren't
as effective but they didn't just blend
the apples they bake them for 45 minutes
first which may change how the body
handles it
so i've seen all these studies was just
not convinced there was a solid versus
liquid effect and then
this study was published
a solid fruit salad raw apples apricots
and bananas with three cups of water to
drink or
take two cups of that water add to the
fruit make a fruit smoothie and then
just drink that third cup of water ah so
the identical meal one in solid form
one in smoothie form what happened
people felt significantly less full
after the smoothie same amount of foods
same amount of fiber but in smoothie
form it just didn't fill people up as
much as eating fruit on natural
originally we thought it was the lack of
chewing the act of chewing itself may be
a satiety signal and i've eaten enough
signal and indeed comparing 35 chews per
mouthful to 10 chews per mouthful if you
ask people to eat pasta until they're
comfortably full
those forced to chew 35 times per bite
ended up eating about a third of a cup
less pasta
so there we have it we have the proof of
solid versus liquid effect we have the
mechanism here and
as so often happens in science just when
we have everything neatly wrapped up in
a bow
a paradox arises in this case the great
soup paradox
soup
pureed blended soup essentially a hot
green smoothie of blended vegetables is
more satiating than the same veggies in
solid form the same meal in liquid form
was more filling than in solid form
so it can't be the chewing in fact there
doesn't appear to be a solid versus
liquid effect at all since cold
smoothies appear to be less filling but
hot smoothies appear to be more filling
so filling that when people have soup as
a first course they eat so much less of
the main course that even when you add
in the calories of the soup they eat
fewer calories overall
so how can we explain this paradox
maybe
pureed fruit is less filling than solid
but pureed vegetables or more filling i
guess you could try making apple soup or
something but who's gonna do that
purdue university to prepare apple soup
they mixed about a cup of apple juice
with two cups of apple sauce liquefied
in the blender and heated it up
if you have people eat three actual
apples instead
they start out pretty hungry but within
15 minutes of apple eating they were
hardly hungry at all
drinking three cups of apple juice
didn't cut hunger much at all but what
about the soup which was pretty much
just hot apple juice with applesauce
mixed in it cut hunger
almost as much as the whole apples even
more than an hour later
and even beat out whole apples for
decreasing overall calorie intake for
the day
what's so special about soup what does
eating soup have in common with
prolonged chewing that differentiates
them from smoothie
drinking
thyme
it took about twice as long to chew that
many times
and think how long it takes to eat a
bowl of soup compared to drinking a
smoothie
eating slower reduces calorie intake
or
maybe we just imagine the soup to be
filling and it's like a placebo effect
feelings like hunger and fullness are
subjective people tend to report hunger
more in accordance with how many
calories they think something has rather
than the actual caloric content if you
study people with no short-term memory
like in that movie memento where they
don't remember what happened more than a
minute ago
they can overdose on food because they
forgot they just ate which shows what
poor judges we are of our own hunger
it's not just subjective effects in this
famous study mined over milkshakes if
you offer people two milkshakes one
described as indulgent decadence you
deserve
the other sensible guilt-free
satisfaction
people have different hormonal responses
to them even though they were being
fooled and given the exact same
milkshake
and finally maybe it was just
that the soup was hot and warmer foods
may be more satiating
so how do we figure out if the solution
to the soup mystery was time
thought or temperature
if only this study had a third group
they had a solid eating group and a
liquid drinking group if only they had a
liquid eating group too
and they did
they also offered the fruit smoothie in
a bowl cold to be eaten with a spoon
very unsoup-like so if it was thought or
temperature the fullness rating would be
down by the liquid drinking the smoothie
but it was just a slowed eating rate
that made soup as filling as solid food
then the number would be up closer to
the solid eating group and it was
exactly
as high
meaning the only real reason smoothies
aren't as filling is because we gulp
them down but if we slip them slowly
over time they can be just as filling as
if we ate the fruits and veggies solid
wow this this study thought of
everything
you don't know the half of it they also
wanted to see if it would work with high
fat smoothies so uh
what almond butter or walnuts no the lf
drink was a liquefied fat smoothie of
steamed pork belly
i guess sometimes smoothies
can suppress your appetite
you