I think I need
to go over the basics of sugars. There seems to be a lot of misconceptions about how the
different nutritive sweeteners relate to each other.
"Sugars" usually refers to a simple carbohydrate. Carbohydrates are, like the name suggests,
made of carbon plus some amount of hydrogen and oxygen in the same ratio as in water,
2 to 1. For example, C6H12O6 is the chemical formula for glucose, and also for fructose
and galactose. They only differ in the arrangments or bonds inside the molecule. Each of these
is called a monomer sugar or reducing sugar. When we join these monomer sugars together
with a chemical bond, we get a polymer sugar, or polysaccharide, like starch or glycogen
or cellulose, which are made up a long chain of simple sugars. For example, cellulose,
the plant material that makes up most of paper or wood, trees and leaves, is a very long
chain of glucose molecules.
The sugar that we are mostly familiar with, sucrose or table sugar, usually made from
sugar cane or sugar beets, is actually a DIsaccharide, meaning made from two monomer sugars. It is
composed of one glucose and one fructose joined by a bond called a glycoside linkage. So we
could say that sucrose is 50% fructose and 50% glucose, joined together by a chemical
bond.
High fructose corn syrup comes in many forms, but the one most often used is called HFCS55,
which indicates that it's composed of 55% fructose, and 43% glucose. The missing 2%
are actually longer polysaccharides similar to starch, and they're a byproduct of the
manufacturing process. So, table sugar is 50% fructose, and HFCS55 is 55% fructose.
The only difference is that in the HFCS, the sugars are not joined by a chemical bond.
They exist as monomers in solution.
Does that matter? Not really. Your body is exceptionally good at breaking that single
glycoside bond. You have enzymes that break sucrose into fructose and glucose as fast
as it can reach it. Within milliseconds, your body has a hard time distinguishing between
sucrose and HFCS, except one has about 5% more fructose and 9% less glucose. We shouldn't
ignore that small difference, either.
Why am I emphasizing the fructose here, but not the glucose. Simple: fructose is the Adolf
Hitler of monosaccharides. It's evil incarnate. Okay, no not quite that bad, but it is the
sugar that is most strongly linked to all the health problems we now associate with
excess sugar consumption. It's a very long list: heart disease, non-alcoholic liver disease,
lipid dysfunctions, Type 2 diabetes, obesity, metabolic syndrome, accelerated aging, gout,
memory loss, dental cavities, and many more.
Why are we even using it then? Yet another plot by the Illuminati to destroy people's
health? Nothing so glamorous. We use fructose-containing sweeteners because fructose is the sweetest
sugar. Fructose is well over twice as sweet as glucose, the other monomer in sucrose.
The fructose monomer alone is about 70% sweeter than sucrose, which as I said is partially
made from fructose. That means that we should be able to use a little less of it to get
the same sweetness, reducing calories and total consumption of fructose.
Glucose is easy for our body to metabolize. It can go straight from the intestinal wall
to your blood sugar. Fructose, on the other hand, usually has to travel to your liver
to be converted to glucose before it can be used. That changes the way your body reacts
to it. Blood glucose following a meal usually goes steadily up, but in the case of fructose
containing sweeteners like sucrose or HFCS, the process acts in two stages. There's the
initial spike as the glucose is metabolized, and remember here that HFCS is only 41% glucose,
so the size of the spike should be smaller. That may reduce the sensation of fullness
by a small amount vs. sucrose. The fructose take a few hours to be converted in the liver
to glucose. Because the body is no longer anticipating a rise in glucose, that excess
glucose is more often converted to storage glycogen, which feeds into fat metabolism.
We've decoupled eating and the sugar spike with fructose-containing sweeteners, and that's
a big part of why these make us fatter.
A recent research study suggests that this little difference of 5% more fructose and
9% less glucose may have a larger effect on obesity and metabolic disease. I'd like to
go through this specific paper in a separate video, because it will provide an excellent
example of how to read a research paper, so keep an eye out for it a little later.
Here's a quiz question, folks. Anyone remember why it's called fructose? Because it's found
in a lot of fruits! Basically any fruit grown on a tree or vine is going to be quite high
in free fructose. Dried figs are especially high, apples, peaches, nectarines, pears,
etc. Also grapes, cherries, yams, carrots and beets. So when you see that something
is labeled "no sugar added" look more carefully at the label. They often add something like
apple or grape juice instead, which can actually be higher in fructose than high-fructose corn
syrup.
Does that mean you shouldn't eat fruit? Not really. The fiber found in most of these slows
down the absorbtion of the sugar, so you won't see as much of a spike in blood sugar. I'd
advise watching very carefully how much fruit juice and certain low-fiber fruits you're
eating or serving your kids if you have concerns.
A sugary 12 oz Coke (355 mL to my European viewers) contains about 39 grams of carbohydrate.
I assume that about 20 grams of that is pure fructose. The same amount of apple juice may
contain 42 grams of sugar, but may actually contain MORE than 20 grams of fructose. If
you want the sweet taste of apple, I suggest you eat the skin and pulp.
Other foods that are very high in fructose are applesauce, honey, pears, agave nectar,
grape juice, pomegranate juice, and dates and watermelon. Some of these have more fructose,
per weight, than a sugary soda.
Here's why HFCS is so evil. It's being over-used. We're drowning in it, as the critics say.
The politics of corn production in the US are complicated. It's one of our top exports,
and keeping it in excess production is politically popular, and may be the result of foreign
trade policies. We export a lot of ag products, and corn is one of the most fungible of those
exports. It can sit in a silo for a long time, and we've found a billion and one uses for
it. From the perspective of the environment, it's not a great crop, but from the perspective
of yield it is. Farmers can make a lot of money from it, and politicians seem to love
subsidizing corn to keep it cheap, which feeds industrial growth, which supports economic
growth and stable prices. It also supports the obesity epidemic and healthcare crisis.
Industry loves HFCS because it ships and stores very easily, unlike granular sugar which is
very moisture sensitive. It's already in solution, so all you have to do is add it to the manufacturing
batch, as opposed to granular sugar which must be dissolved into a simple syrup before
addition.
The reason HFCS is evil is because we like it so much. I'm not convinced that sucrose
is any better, but it's ever so slightly more expensive and harder to add to a liquid product,
and that may make a beverage company hesitate for half a second before doubling the sugar
content in a soda to cover the fact that they are also adding salt to make you more thirsty.
Consumers are driven by their biology, adapted to desire the sweetness of ripe fruit, loaded
with fructose. Companies are driven by profit to give customers what they're willing to
buy. The collision of those two motivations is an obese, diabetic country.
HFCS is a problem because kids are drinking sugary sodas at a young age, and as a group
we're drinking too much of them. Our fructose consumption is too high. That's not because
HFCS is chemically very different than sucrose, it's because manufacturers like to use a lot
of it. We could be killing ourselves just as easily with cane sugar, but it would cost
us a few extra bucks a year. HFCS is just putting up hand rails and lighted paths on
the road to our self-destruction. We're the ones walking along it.
So how much added sugar is too much? Don't forget c0nc0rdance's first law, Never take
medical advice from the Internet. A doctor is always your best bet for health advice.
However, the Mayo Clinic and American Heart Association both gave the same figure. No
more than 100 calories for women, no more than 150 calories for men, and less is always
better. One can of coke or similar soda is about 100 calories of added sugar, so limit
yourself to about that much per day or less.
You want a little personal advice from me to you? Pick up the water habit. Add a little
twist of lime or lemon and some ice. You'll be a lot more refreshed and a lot healthier
as a result.
I'm anticipating at least one person in comments is going to promote Stevia, a non-caloric
sweetener extracted from the stevia plant. This is a very popular sweetener with health
concious people, but I actually have some concerns about stevia. It's going to have
to wait for a later video on the non-nutritive sweeteners like Aspartame and Splenda but
let's just say we don't know much about it, but what we do know is a bit troubling. Stick
to natural sweetness of foods if you can. If you can't, focus on moderation.
Honestly, I think we all understand that cotton candy is not health food. Neither is a sugary
soda. Neither is a giant steak, dripping with bourbon butter. Our evolution is working against
us here. We crave the things that our distant ancestors were least able to obtain. Ripe
fruit, seared meat, salty snacks. Unlike those ancient peoples, we are able to obtain these
things at little expense. Now we must learn to master our animal instincts, to behave
like civilized people. We must demonstrate discipline, restraint, and wisdom in what
we eat and what we do.
I'll quote something I heard the other day that summarized, in exactly seven words, how
to eat well. "Eat food. Not too much. Mostly vegetables." I think that's the kind of wisdom
I can just about handle.
Thanks for watching.