When we think about Nutritional Science, we don't always stop to think about how
we got here or who helped us gain the knowledge we have today.
Diseasees associated with nutritional deficiency were actually documented as
far back as 2600 BC. Influxes of nutritional disease have
occurred throughout history often in relation to the economic status of a
region. To put it simply, if we could eat well
nutritional deficiencies were less prevalent.
Conflicting theories and limited models help to slow the progress of nutritional
discovery, but in the end science did find out what you do not eat may kill
you. To begin the discussion of vitamin
deficiency discovery, we must first consider the theories that helped medical
science but may have hindered nutritional discovery.
Early researchers believes that one could design a perfect diet based on chemical
content alone. And Dr.
Louis Pasteur's work in bacteriology helped actually promote medical advances,
but limited the idea that it wasn't something that was infecting you causing
disease, but it was something that was missing.
The word vitamin didn't even enter our vocabulary until the early 1900s.
Before the chance before researchers got the chance to duke it out over their
theory. Epidemiological evidence did exist that
diet may be related to disease. You eat something, you get better,
that's a really easy research study to do.
And people were dying from nutritional deficiencies, but nutrition science did
not really advance until the early 1900's.
Thiamin is recognized as the oldest vitamin.
And it was the first to be discovered Beriberi a disease that results from
thiamine deficiency was documented as far back as 2600 B C in China.
The disease was noted to be prevalent in barracks and prison and increased when
brown rice was replaced with polished or white rice.
Early researchers in the 1880s thought that perhaps there was something wrong
with the foods, a toxin. And they observed that navy sailors were
spared death by Beriberi. When their primarily white rice ration
was bolstered by other foods. Initial hypotheses from those are, were
that it was some protein, so they're adding more foods.
It must have been some protein that were curing Beriberi.
A Dutch researcher, Christian Eijkman, observed that symptoms of Beriberi looked
similar to a condition in chickens called polyneuritis.
And in some early research with these chickens, as you can see here, he fed
different chickens different diets. He found that sick chickens got better
when they ate brown rice. And healthy chickens didn't get sick when
they ate brown rice. But sick chickens and healthy chickens
alike, died from Polyneuritis, when they were fed the white rice.
So his first hypothesis that was, first his, his first thoughts was that in that
white rice must have been some toxin. Again, we're thinking about bacteria,
we're thinking it might be an infection, it must be something that's in it, not
something that's missing. Later, a series of researchers, including
Dr. Grijns, Captain Vedder, Mr.
Chamberlain, and Dr. Casimir Funk, helped advance science and
learn a little bit more about thiamin. They deduced that it was actually a
missing component, not this idea that there was an infectious agent leading to
Beriberi and discovered that something about rice polishings, the holes of rice,
what we take away when we make white rice, was preventing the condition.
And people are actually treated this way. We feed them rice polishings, and they
get better. They don't get Beriberi.
And it was Casimir Funk that actually isolated this vital amine, found
thiamine, and vitamins were born. Another B vitamin, the compound Niacin,
was actually recognized by chemists since 1867.
And Mr. Funk, he actually did isolate it back in
1911, but he was looking for the cure for Beriberi and Niacin didn't do the trick.
Niacin, like thiamine is associated with another disease called Pellagra.
Pellagra was actually first considered to be a disease of a corn consuming
population. As corn consumption spread across the
U.S., and even when it came to the U.S. pellagra followed.
It was prevalent in the late 1700s and entire hospitals were actually
established just to treat pellagra. Here in the U.S.
we had a pellagra hospital. It was mostly associated with lower
income populations, particularly with prisons and orphanages.
As we look through history at economy and actually cotton, we can see changes in
pellagra. Towards the end of the war, as cotton
prices went up. Cotton farmers made more money, they got
to eat better, pellegra disappeared and hospitals actually shut down.
But once cotton prices fell, when the farmers where less able to buy healthy
foods, pellagra reappeared. Over time, as cotton was no longer a
valuable crop and farmer's started growing food crops, and therefore they
also ate better, pellagra also disappeared.
But still, people thought there must be some infectious agent.
But a researcher named Goldberger was the first to question this theory, just like
his predecessors with thiamine. Dr Goldberger was charged with
identifying the germ that was causing pellagra, even though he didn't think it
was a germ. He recognized that yes, in prisons and in
dirty conditions Pellagra was rampant, but the guards did not have pellagra.
Yes, in orphanages even, he was seen pellagra.
But the children in the middle age group were the ones most affected.
Those children, couldn't go out and work and earn more money eat a little bit
better. They were also not given milk because
they were old enough to eat other things. So if this was infectious why wasn't
everybody getting it? So if you've ever not liked an assignment you've given,
been given by a professor or your mentor gave you a project you weren't too
thrilled with, think about Goldbergers' graduates students.
Goldberger actually proved that this wasn't an infectious agent by generating
his filth squad. And he and his filth squad went into
prisons and ingested and injected the biological samples and excretions from
individuals with pellagra, think about that.
And yes, they probably got sick in other ways but nobody developed pellagra.
And Goldberger even predicted as poverty continued, pellagra would too,
and he was correct. Despite others still saying there was an
infection, he continued to work In finding a way to prevent pellagra until
he'd actually died. And it was in the early 1930s, after an
animal model was discovered, that we figured out what was really going on.
In the early 1930s, Dr. Elvehjem was able to determine what this
compound was. He found an animal model,
it was the dog. And a condition called the black tongue,
kind of like the chickens back with thiamine.
Black tongue was related to pellagra in humans.
By curing, by curing black tongue in dogs, he was able to do research isolate
the compound, and determined that it was Nicotinamide, or Niacin, that was the
missing component, and the cure for Pellagra.
The final key in this whole poverty puzzle, what people were sort of confused
by, was why was protein alone helping prevent Pellagra.
The key there was the discovery that the amino acid Tryptophan actually makes
Niacin. So either eat niacin or eat tryptophan,
and you won't get pellagra. The last vitamin I'm going to talk about,
vitamin C's claim to fame, is scurvy. You might have actually heard some jokes
about scurvy dogs or those limey sailors. Incidences of scurvy actually date back
to ancient Egypt, Greece, and Rome. It was a disease that was associated with
winter and early spring when vegetables and fruits weren't available.
And it was highly precedent, it was highly prevalent in the seagoing voyages.
Early explorers, the Vikings, naval troops were all worried about this
disease. I mean, you can't find a new land or go
on a mission if everybody's dying of scurvy.
And it was the ships that thought to bring limes and lemons aboard that were
not coming down with scurvy. Early explorers also learned from
American Indians that they had a cure for scurvy, was an infusion of pine and
spruce needles and so they also helped these explorers with the condition.
In 1747 James Lind helped us out by discovering the anti-scurvy nutrient.
He realized that it was actually the lemons that were going aboard these
ships. And from then on British fleets were
charged with carrying always, lemons and lime juice on their trips.
And that's where the limey nickname came from.
During the 19th century Scurvy continued to spread including in children creating
infantile scurvy. And this actually stemmed from
individuals sterilizing milk, so killing off nutrients.
And it wasn't until the mid 1900's that we recognized that it was a Vitamin C or
ascorbic acid that was the missing link to preventing scurvy.
So now it's your turn. What nutrients have I missed? Look up
some history about the vit, other vitamins.
How was vitamin B12 discovered? What did iron deficiency anemia have to do with
falling in love? And why might vitamin D be for the hard headed? Find out, look it
up and share it with me in the class.