*Intro tune plays* Humans love sweet things. We've evolved to value sweet foods when we come across them. But in a relatively short amount of time we've learned how to make things sweeter artificially. In some ways this is obviously amazing because it's delicious, but in terms of health and the science of food it's been confusing. Our brains think we are still getting sugar even when we're not. and we can be a little bit judge-y about what we think sugar does to people's behaviour, especially kids. So to give some more context to what we know about what we know about humans and sweetness, we wanted to put our videos about sugars and sweeteners here in one place. First from one of our earliest SciShow videos: Why do we love sugar? This, my friends, is your run-of-the-mill table sugar, It's made from either sugar beets, or, uh, from sugar cane, but there's no way to tell which. But henceforth we're going to be, uh, calling it by it's proper name, which is Sucrose. There's a bunch of different kinds of sugar but they're all sweet-tasting edible carbohydrates. Ah! Carbohydrates, probably the tastiest word in the English language! And beside from filling up yo' snack hole and making yo' kids all spazzy sugar is one of the most important chemicals on the planet. They're pretty much the primary source of energy for everything on Earth. Not this stuff exactly. This stuff is more of the, uh, primary source of all cavities on Earth. At the cellular level pretty much every living thing on Earth, when it needs an energy fix, whether it's a plant, an animal, a bacteria, the first thing they turn to is sugar. Now where does sugar come from? Or at least the energy to make sugar come from? That, of course, is our friend, the Sun. These lovely, sweet, compounds are found in every single plant, though in vastly varying quantities of course because it is the primary product of photosynthesis. But for now let's just say that the importance of plants turning carbon-dioxide, and water, and sunlight, into sugar cannot be over-stated. Basically, plants use energy from the sun to split molecules of water and the hydrogen from that water is combined with the carbon-dioxide to create glucose. So in effect this process catches the energy of the sun, and stores it as chemical energy in sugar. I'm eating the sun! I'm eating the sun. Right now. It's under my tongue. Problem! That was a lot of sugar. I'm worried I'm gonna have a stomach ache. In addition to glucose, another common plant sugar is fructose, which has the same chemical formula, It's just... rearranged a little bit. And even though they're very similar and contain the same amount of energy, fructose actually tastes significantly sweeter. Which is why we like to put high fructose corn syrup into beverages. That's why we get a wide range of tastiness in plants from super sweet potatoes to not sweet at all potatoes... complex carbohydrate actually bunch of
sugar molecules all linked together all the way to the sugar and sugar cane with
her old friends sucrose which is actually just a molecule of glucose in a
molecule of fructose linked together . is that all these sugars are important
the reason why we think they're so delicious is because we need energy to
survive and sugar is a really great place to get energy from and if it seems
to you like I've been eating a lot of sugar in this video keep in mind that I maybe add about 2 to
3 TSP so far the average American has about twenty
two per day so I got a long way to go 22 teaspoons day people that cannot be
healthy i did a little bit of research and I discovered last night that just
from drinking soda the average American drinks about 50
pounds of sugar a year we Americans generally have a heck of a lot more
sugar than we need to have was probably having more like six to nine teaspoons a
day you might want to rethink that all Cap'n Crunch diet you're currently on
her not really designed for a world where sugar is infinitely available it's
generally pretty hard to come by something really sweet in nature and
even if you find something like a bunch of apples hard to eat a lot of apples
without making yourself pretty sick nowadays we've got around that by
producing this wonderful white powder as well as the high fructose corn syrup
that they put an absolutely everything these days so if you want my health
advice try and maybe eat the way that your
caveman ancestors did fruits and vegetables maybe some complex
carbohydrates here in there and i would suggest overall to not consume sugar in
this manner now 2012 Hank just mentioned in that
episode that fructose is much sweeter than glucose but they are both plant
sugars so why all the hate for high fructose corn syrup well here's a video about that very
thing people just seem to love to hate stuff that tastes good these days
sometimes there's a good reason for of cars but sometimes I feel like we're
just we're just giving ourselves a hard time when I was a kid for example every
kitchen I ever went into was full of fat-free stuff because everybody's mom
had heard on some morning show that if you eat anything with fat in it you're
going to turn into an overstuffed walrus shaped couch cushion so we always did
things like bagels slathered in margarine and and sometimes that come
home from school you a whole box of fat-free cookies because they're fat
free it doesn't matter how many you eat what
why don't you even do this so now people are eating fatty things
again and I mean thank God not what I'm going at the moment though instead of
that the new Dark Lord of nutrition is high fructose corn syrup and I checked
there is no high fructose corn syrup in this corn dog people despise it we've
gotten so up in arms that food companies are now taking it out of their products
and replacing it with all natural sugar to hear a lot of people tell it hfcs as people have started calling it
to make it sound more chemical e is the enemy love it all things good and pure and the
sole cause of the obesity epidemic speaking of the obesity epidemic i did a whole show on that you should
watch it anyway you know as they say on the internet haters gonna hate let's say
that on the internet is that an urban slang thing but do the haters have a
valid point and we've been doing research on this and we're not quite
sure actually high fructose corn syrup is kind of a
wonderful creation really it's extremely inexpensive it easy to transport easy to mix into things that it's made
food a lot cheaper and certainly made every calorie that we eat in America
cheaper oh this is of course all with the help
of 40 billion dollars of subsidies to corn farmers for all these reasons and
more the use of high fructose corn syrup has been skyrocketing since the nineteen
seventies and now if you're eating something sweet is about a fifty percent
chance that that sweetness is coming from high fructose corn syrup that said
on the surface of things sucrose which we know as cane sugar or all natural
sugar or table sugar and high-fructose corn syrup are basically the same thing they're both plant-based sweeteners and
on a molecular level they're pretty similar. Both sugar
and high-fructose corn syrup are made out of glucose and fructose chemically
sucrose is just a glucose molecule and fructose molecule bonded together while
high fructose corn syrup is just a mixture of glucose and fructose
molecules without them being bound together the molecule for molecule
fructose actually tastes a lot sweeter to us and I should point out that
fructose is called fructose because it's the kind of sugar that we generally find
in fruits so if i have heard those corn service basically just glucose which is
the most common sugar in the universe and fructose which is the kind of stuff
that you find an apple juice how could it be that bad for you what makes us so
suspicious well we have this graph right here yeah that's the obesity rate in
America going through the roof right about the same time that every single
product in the grocery store started getting enhanced with high fructose corn
syrup and that is a correlation not causation but it is a correlation worth
investigating for example some recent studies on rats are beginning to show
that high fructose corn syrup makes the rats way fatter than if they just a
table sugar and it's also raising levels of fat content in their blood but there
have been a lot of other studies that have shown no significant change
depending on whether you're eating table sugar or high-fructose corn syrup one
thing however is certain that high fructose corn syrup is in a lot of what
we're eating these days it's making sweet foods much less expensive and so
the barrier to consuming them is lower and it is very rewarding to have an
ice-cold coca-cola so there's a combination of economics
biochemistry brain chemistry and in general people eating sugar of all kinds
which probably isn't very good for us but it's not just about table sugar
versus high fructose corn syrup nowadays there are tons of different
ways to sweeten things artificially and each way binds with our taste receptors
differently here's more on the science of sweetness so you've got your tongue at least I
hope you do and it's covered with tons of lingual pillai commonly known as
taste buds which are what make eating so enjoyable taste buds are chemoreceptors
which means that they translate the bio chemical makeup of food into electrical
signals to the brain knows what it's tasting each day spot is made up of
clumps of 50 to 100 taste cells proteins that bind with food molecules to allow
us to detect specific flavors in general humans tend to go for salty and sweet
stuff and avoid overly bitter and sour taste probably because of nature those
tastes often indicate that a potential food is poisonous. Physiologically
the body associate sweet taste with high calorie and therefore high energy foods - it's
desirable! Most animals in the world can enjoy sweetness is well with the
exception of those in the cat family. Cats can't taste sugar because they lack
the genes that generate the sweet receptors. Perhaps because they evolved
the only meat. Makes me feel kind of sorry for them. But of course we humans can't
get enough of sweet and we've got the dental, diabetes, and obesity issues to
prove its not only can we taste sweetness but we are connoisseurs of its
delicate range of flavors from honey agave and maple syrup to fructose and
glucose and plants and fruits and good old sugar bowl sucrose as well as more
reason to adaptations like high fructose corn syrup and the host of artificial
sweeteners on the market. We can taste them all and we can tell them apart.
Natural sugars trigger our taste buds immediately filling our senses with all
kinds of goodness before gently fading away without leaving any aftertaste.
Chemically it's a beautifully simple process but it is maddeningly elusive to
duplicate which is why synthesizing the taste of real sugar has become a sort of
Holy Grail quest for food chemists. So far no one in my opinion anyway has
even come close. That's because when you lick that
beautiful powdered sugar off your fingers the sucrose molecules act like a
key that unlocked a sweet sensation on your tongue and in your brain. Meanwhile
your digestive enzyme start metabolising that sucrose giving you energy to move
around and do your happy dance of course if you don't use all that
energy it sticks around as fats artificial compounds affect our taste
buds in a similar way to natural sweeteners but because they're molecules
are structured differently they bind to are receptors much more aggressively and
so their sweetness comes across not as a gentle flavor fairy kiss so much as a
slap in the tongue which is why saccharine tastes about 300 times
sweeter than playing sucrose and can leave a metallic like aftertaste interestingly most other animals are
unable to taste these artificial sweeteners because their taste buds are
set up differently. Each artificial sweetener has a different molecular
shape so each binds to our taste receptors in a distinct way giving a
signature flavor to their on natural sweetness. That's why a typical
diner will have a colorful display of different packets ready to sweeten your
coffee. And one thing that almost all of these lab created sweeteners have in
common is that they don't contain any calories or energy because our bodies
cannot metabolize them. So they just slide through guts without being absorbed. Some
kinds are low calorie but they're so bonkers sweet that just a dab'll do ya so
even if they are metabolized it's caloric payoff is negligible. So now
let's take a quick look at what's going on in that table ramekin rainbow. First we got your average joe packing a
white sugar bowl of sugar or sucrose. This white stuff is either refined from
sugar cane or sugar beets and there is no way to tell which was by the time it
reaches the packet face but it is chemically the same thing. If you're in
like a newfangled hippy cafe there may be a green packet in the mix - that's stevia, the new guy. Stevia is derived from the sweetleaf
stevia plant, a perennial shrub native to Paraguay and Brazil. The Stevioside
compounds that make its leave sweet can be isolated and refined into an intense
powder. Stevia is calorie free because our bodies can't metabolize it just like the
synthetics this makes it very low on the glycemic
index meaning it doesn't raise your blood sugar even though it's 300 times
sweeter than sugar so they have to actually cut it with other stuff.While
South Americans have been using stevia for ages it's pretty new to the US
market and only recently did the FDA approved it as a food additive. Now, if you're
sitting at the table drinking coffee with your grandpa you might see him reach for a pink
packet of saccharin, the first and oldest of all the artificial sweeteners, saccharin
was accidentally discovered in the late 1870s by a chemist working with coal-tar
derivatives. One day he forgot to wash his hands and noticed that night at
dinner that his fingers tasted sweet. This is going to be a repeated story
throughout this episode. Teddy Roosevelt was a big fan of saccharin and it gained
popularity during World War one when sugar was scarce. In 1957 it was branded as sweet and low. If
you're old enough to remember your mom drinking cans of Tab soda you may
remember anything containing saccharin used to come with a warning label
declaring that it may cause cancer. A bunch of lab tests in the nineteen
seventies links saccharin to bladder and other cancers in rats and the FDA tried
to ban the stuff in 1977 but Congress intervened and suggested that it carry a
warning label instead. Which hardly kept people from drinking it after extensive lobbying from the diet
food industry and sufficient claims that earlier studies were flawed the label
was removed in 2000. It's still the same compound though so it's more or
less up to you to decide what you make of all that. Next to the pink come the blue
sachets of aspartame. It was discovered in the 1960s when - yes another chemist
absent mindedly licked his finger to grab a piece of paper while testing a
new ulcer medication. Thank you sloppy chemical technique. Aspartame
popped up in products in the early 1980s as an alternative to saccharine. It's
about 200 times sweeter than sugar and unlike other synthetics our bodies can
metabolize it so it does have a few calories. Once digested aspartame breaks
down into three components the amino acid phenylalanine and aspartic acid as
well as methodal which is better known as wood alcohol. And finally you have
that sunny yellow sucralose. Sucralose was originally marketed as tasting like
sugar because it's made from sugar and it is! It's made by reacting sucralose
with chlorine, a toxic chemical. It too was accidentally created in the
mid-nineteen seventies. In London a student and his advisor were working on a new DDT-like insecticide. By slowly adding the toxic chemical sulfuryl chloride to
a sugar solution the resulting reaction formed a new
compound tetradeoxygalactosucrose. Then as
legend has it the student was told to test the product but misheard and tasted
it instead. It was crazy sweet it was sucralose. To make sucralose you have to replace some of the oxygen and hydrogen groups in a sucrose molecule
with chlorine atoms at which point it isn't sugar anymore but it is 600 times
sweeter. Those chlorine particles prevent us from metabolising sucralose making it calorie free and it also makes the molecules heat-resistant enough to be
used in baking - something other artificial sweeteners can't handle.
Maybe
by now you're wondering about the potential risks you've heard associated
with artificial sweeteners. So are they safe, or what? Well first remember that
anything you buy at the grocery store to sprinkle on your cereal has been tested
and approved and is regulated by the FDA as being safe enough. Even if it uses
toxic chemicals in the processing it's not a toxic chemical itself. However a
lot of people are still wary of these lab creations including some of the
researchers that make them. Critics argue that these
products haven't been around long enough to truly measure the cumulative effects
of a lifetime of consumption. Some new studies are suggesting that certain
products may not be as benign as we once thought. A European Union funded study
published in 2010 for instance found that pregnant women who drink diet sodas
appeared to be at greater risk of premature birth. While other research on
aspartame linked to several types of cancer in rats and yet other studies
have found that daily diet soda intake substantially increased the risk of type
2 diabetes. And that's one of the potential health effects that's getting a
lot of attention these days specifically researchers are looking at how
artificial sweeteners can interfere with the brains natural ability to count
calories which can actually lead to weight gain. I mentioned before that the tongue and
brain associate sweet things with calories, which are straight up energy. The brain knows how many calories the body needs to get by so it understands
that A) a banana taste sweet and B) it gives a certain amount of energy to keep
me satiated for a certain period of time, so I can stop eating now. But the
theory is that artificial sweeteners are basically dirty rotten Liars when it
comes to your brain. Guzzling a gallon of diet soda only retrains your body to
stop associating sweetness with calories. Pretty soon you're eating that banana
again and the brain underestimates the true calorie count of said banana and
wants to keep eating. One study found that rats fed artificially sweetened
yogurt with their normal rat shall gained more weight than those eating
sugar sweetened yogurt. It was like the artificial sweeteners were deprogramming
the animals natural ability to keep tabs of its calorie intake. Your brain is used
to associating sweetness with calories and calories with satiation. Sweetness
without calories can confound the brain and potentially lead to more craving and overeating. We may fool our tongues but we can't fool our brain. So in the end
it's up to you what you want to put in your body but anyway you swing it,
moderation seems to be the key. Now in that episode I kinda lied to you. I said that
saccharin is the oldest of the artificial sweeteners but in truth there
is an artificial sweetener that is even older. Lead: also more deadly. As elements
on the periodic table go lead is pretty handy. Not exactly oxygen
or nitrogen but it has some admirable qualities. Like, it's heavy but soft and
malleable. In the form of lead dioxide it's highly conductive, which makes it
useful in batteries. And it's so incredibly dense that it's great at
blocking out things like ionizing radiation. Lead is good for all
sorts of things but it is also poisonous really very poisonous. And for the last
5,000 years or so humanity has been so enamored of all of its wonderful traits
that we've been killing ourselves with it. When inhaled or ingested let is
readily absorbed into the blood where it can slow down the transport of oxygen
and eventually build up in your kidneys, brain, liver, heart, and especially bones
and teeth. Once it's in the body lead not only displaces metals you actually need like calcium, iron, and zinc but it's excellent at blocking receptors
for glutamate - the most important neurotransmitter for normal brain
function and learning. Lead poisoning can affect nerve transmission to the brain
and cause abdominal pain, anemia, and the loss of developmental skills in
children. So what makes this naturally-occurring heavy metal so
valuable that we overlooked it's terrible side effects for so long?
Well because of it's nice combination of softness, durability, and availability the ancient Romans and Greeks used lead in practically everything - from their plumbing and eating utensils to their
writing tablets. But the Romans in particular really liked to eat it. Don't test this out but lead actually has a naturally sweet taste and Romans sprinkled lead acetate into their wine to sweeten it. They called it sapa and it was consumed in massive quantities by
the aristocracy It was also found to be an effective
preserve it is because you know it kills stuff. According to some historians the
common use of this led additive caused widespread infertility and dementia in
ancient Rome - especially among the ruling class so think about that next time you're
wondering whether aspartame is bad for you. The Romans wanted sweeter wine so
bad they put LEAD in it. Lead has been used in paint for thousands of years as
well and it's so useful that we kept using it through the late 20th century well after we understood its dangers. In
particular lead carbonate, otherwise known as white lead was widely used because it
made paint so opaque that a small amount of lead-based paint can cover a large
area. It's also highly insoluble meaning that
it doesn't dissolve in water making it great at resisting the moisture and mildew that can cause other paints to crack over time. lead carbonate can prevent
decomposition in the oils that makeup paints allowing them to look fresh
longer. And lead-based paints dry faster than their counterparts. There was so
much to like about lead paint except for the part where it killed a
bunch of people because people did get poisoned from lead paint - especially
children either from inhaling dust with flakes of the paint in it or just
because as previously mentioned lead makes things sweet and kids like sweet
things even if the sweet things are paint chips. The federal government
finally banned the use of lead in paint in the u.s. in 1978 but lead was still
all over the place particularly in the air because of cars. In addition to its
use as a wine sweetener and a paint improver lead offered even more
benefits as a gasoline additive in the form of a compound known as tetraethyl
lead. In the early nineteen twenties car makers were looking for a solution to engine knock. See the engines work best
when the fuel than the cylinder burns all at once and at the exact moment the
spark plug fires. But sometimes especially in older cars or with cheaper
fuel the fuel would actually ignite before the spark plug fired, damaging the
pistons and cylinders in the engine and making an audible pinging noise. But tetraethyl lead to increased the
ignition temperature the gasoline eliminating pre-ignition. But of course
the lead was released in the car's exhaust which was then inhaled by people
and absorbed into their bloodstream as As with paint it took a while for the
problems associated with leaded gas to show up. But some clues came early like
the fact that workers who handled tetraethyl lead often experience
hallucinations and many of them died at a young age. So in 1974 the Environmental
Protection Agency developed guidelines for eventually eliminating leaded
gasoline. It wasn't easy other additives had to be developed for cars that had
been designed to run on leaded gasoline many of which have their own problems. But in 1996 the last leaded gasoline was sold in the united states and most gas
stations still use labels to assure everyone that even their cheapest fuel
is unleaded So quick review - if you're using lead to
shield yourself from x-rays or make batteries or something like that you're probably doing it right. But if
you're using lead in any way that winds up in your mouth or up your nose or in
any of your face holes then you're using it wrong So yeah, lead is sweet but there is
nothing about it that is good for you. Now if you remember back in the
beginning of this video 2012 Hank made a crack about sugar making kids hyper. Well it turns out kids can just be that
way no matter. What the real interesting thing is how we as adults perceived kids
when we think they've had sugar This last video gives us the sweet and
low down on kids and sugar. If you heard it once you heard it a
thousand times - parents blaming their kids' unfortunate behavior on sugar. And if you've been around kids long enough you could probably see why people make
that connection. I mean a healthy and happy five-year-old
wakes up perfectly fine, has a good morning and then goes to a birthday
party becomes a shrieking moody ball of pure energy and of course it's all from
the cake and sugary drinks and ice cream right? Right?? What else could it be? As it turns out, it's probably just from
hanging out with a bunch of other five year olds and then being pulled away to
go home and be bored the rest of the day. The kid would probably act the same even
if they had no sugar at all. As far as science is concerned there is no
evidence that sugar intake makes healthy people more active not even children. On
the contrary lots of studies have shown that what looks like sugar-based
excitability is really just normal psychological response to a stimulus IE
getting a delicious snack several groups of researchers have found
that the sugar rush we have often come to associate with candied up kids
actually exists just in the perceptions of observers especially parents and
other caregivers. In one double blind study young boys and their mothers were
divided into two groups. One group was told that the boys will be given a
sugary drink and the other was told that they would be given a drink sweetened
with aspartame - the sweetener in Equal But it was a lie! In reality both groups got the
artificial sweetener. After enjoying their little drink the boys and their
mothers were told to just play around for a while and then the mothers were
asked how they thought playtime went Almost invariably the mothers who
thought their sons were given sugar described their behavior more critically than those who thought their sons had been given an artificial sweetener. And
maybe even more importantly, neutral observers in the study described the
mothers in the sugar group as hovering more closely around their boys and being
more critical of what they were doing But really, both groups of kids were just
playing - just being kids. Because of studies like this the National
Institutes of Health has said that there is no link between sugar intake and hyperactivity
in children. But that's not to say that eating loads of sugar can't affect a
person's activity level at least for a little while Sugar enters the bloodstream almost
immediately after its eaten and it can be used if we are currently active. But
our bodies are really really good at regulating the amount of sugar in our
blood so almost as soon as it's absorbed it's metabolized or stored. Otherwise our blood sugar would be
totally nuts which it is only if we have diabetes. The sugar intake doesn't cause you to be
more active, it only allows for a bit of extra energy if you're burning up a bunch of energy
already. So long story short, sugar is delicious and I'm glad it
exists. Like almost anything it can be misused and overused and when that
happens it can cause lots of problems. But in the end, one thing we can't blame
on sugar is our behavior, that of our kids with or without sugar sometimes you
just got to go wild man. thanks for watching this extra sweet
scishow compilation video. If you want to see a compilation of a certain subject
or have questions for us about sugar that we didn't cover let us know in the comments and don't
forget to go to youtube.com/SciShow and subscribe flowers are blooming and very
importantly bees are buzzing we talked a lot about be 0
