Everything Everywhere Daily: History, Science, Geography & More - Vitamin D

Starting point is 00:00:00 Of all of the vitamins and nutrients which are required by the human body, there are 13 of which which are considered essential nutrients. And that means they can't be produced within our bodies. One of those essential vitamins can be produced in our bodies, but it requires a little bit of help to make it. It's a vital component of human health, yet an enormous percentage of the world's population is deficient in it. Learn more about vitamin D, aka the sunshine vitamin, on this episode of Everything Everywhere Daily. What if your perceptions about the past were wrong? ThruLine is a podcast that takes you back in time to uncover the parts of the story that may have gone unnoticed.

Starting point is 00:00:52 It effectively turned day into night. And how it shaped the world now. Time travel with us every week on the ThruLine podcast from NPR. Before I get into the weeds about what vitamin D is and how it works, I should start with the history of vitamin D. The history of the vitamin begins in the ancient world with the diagnosis of the disease that we know as rickets. Ricketts is a disease that affects the bones of children when they're growing. It can result in deformities, soft bones, bow-leggedness, exaggerated foreheads, and in severe cases death. Ricketts was first recorded in the second century by Sonoros of Ephesus, who was a doctor who practiced medicine in Alexandria and Rome. He noted the deformity of bones in certain infants. In 1645, the English doctor Daniel, Daniel,

Starting point is 00:01:42 Whistler identified Ricketts as a specific disease, not just as a collection of symptoms that afflicted children. Rickets would appear in children throughout history, and nobody was sure what caused it. John Snow, the man who famously figured out how to stop cholera outbreaks, thought that it came from bread treated with a substance known as alum. But it wasn't until the 20th century that researchers began to discover treatments for Ricketts that actually worked. The first came from the German doctor Kurt Holschinsky, who immediately after the First World War, discovered that rickets could be treated with exposure to ultraviolet lamps. Around the same time, a British doctor by the name of Edward Mellonby found that he could treat

Starting point is 00:02:21 rickets in dogs by feeding them cod liver oil. Melanby assumed that the substance which cured the dogs was the newly discovered vitamin A, which is found in cod liver oil. However, in 1922, one of the co-discoverers of vitamin A, American Elmer McCollum, repeated the experiment with dogs but removed the vitamin A from the cod liver oil. The dogs still recovered, indicating that it wasn't the vitamin A that was treating the rickets. McCollum named the new substance vitamin D, as it was the fourth vitamin to be identified. Technically, vitamin D is not a vitamin, although it's always treated as one. It is technically a fat, soluble, steroidal hormone. If you remember back to my episode on vitamins, many vitamins are

Starting point is 00:03:04 really Vitamers, which have several different forms, and this is the case with vitamin D. The first type, which was dubbed vitamin D1 and was later found to actually be a collection of different molecules, so vitamin D1 is no longer used. The two main types of vitamin D2 are vitamin D2 and vitamin D3. D2 is known as ergocalciferal, and D3 is known as a chloe calciferal. There are technically vitamins D4 and D5, but they're of minor and relatively little importance. When vitamin D is referred to generically, it is referring to both D2 and D3. So, what does vitamin D do? The reason why cod liver oil was a treatment for rickets is that it's a powerful source of

Starting point is 00:03:47 vitamin D, and vitamin D deficiency was the primary cause of rickets. Of the many things that vitamin D does in the human body, it facilitates the absorption of minerals such as calcium, magnesium, and phosphate. When a child is developing, they're constantly growing new bone mass, so without sufficient vitamin D, their bodies can't develop bones properly. This is the main reason why a generation of children, children was given cod liver oil by their mothers. If vitamin D deficiency could explain why rickets developed in children, then how was it that Kurt Holschinsky was able to treat rickets

Starting point is 00:04:20 with exposure to ultraviolet lamps? In the 1920s, German researcher Adolf Vindhaus and American Alfred Hess found that when a substance found in our skins known as 7D hydrocholesterol is irradiated with ultraviolet light, in particular wavelengths of UVB light, it produced vitamin D3. As Hest succinctly put it, light equals vitamin D. In addition to sunlight, the other sources of vitamin D are dietary. The only major natural sources of vitamin D come from animal-based foods. Seafood is particularly high in vitamin D, including salmon, sardines, and oysters. Eggs and beef liver also contain vitamin D. And there are also some species of mushroom that can produce small amounts of vitamin D as well. Consumption of fatty fish is one of the reasons why people such

Starting point is 00:05:07 as the Inuit who live in polar regions are able to get enough vitamin D, even though they go through much of the year without sunlight. Once vitamin D was discovered, and its importance, especially for children, was known, many foods began to be fortified with vitamin D. Milk, breakfast cereals, and orange juice are the foods that are most commonly fortified with vitamin D today. While Ricketts was the historical disease that brought vitamin D to the forefront, it turned out that vitamin D is involved with far more metabolic functions than just bone growth. Vitamin D deficiency has been linked to a whole host of ailments, including increased risks of certain types of cancer, including skin melanomas, breast cancer, and liver cancer.

Starting point is 00:05:48 A study out of Michigan State University found a 13% increased survival rate among cancer patients who took a vitamin D supplement versus those who took a placebo. Vitamin D deficiency has been linked to reduced cognitive function, which includes everything from brain fog and reduced memory to recall and increased rates of schizophrenia. While vitamin D deficiency can cause rickinson children, it can also cause bone problems in adults. Osteoporosis, brittle bones, and reduced bone mineral content have all been linked with low vitamin D levels. One of the biggest areas of current vitamin D research has to do with vitamin D's role in the immune

Starting point is 00:06:22 system. In addition to a bone growth, it appears vitamin D plays a role in the activation of T cells, T cells being the cells that hunt down foreign pathogens in your body. There are many other ailments, such as multiple skull rube, which have been linked to vitamin D as well. This isn't a health podcast, and I'm not a doctor, so for any individual ailments, I suggest you consult a doctor and do research on your own. However, in the course of doing research for this episode, I was shocked at the number of

Starting point is 00:06:50 ailments of all types, which were correlated with low vitamin D levels. What is undeniable is that vitamin D is really important for the functioning of the human body, and it's involved in multiple metabolic functions within our bodies, some of which we probably still don't even know about. While vitamin D is important, so are many other vitamins. I could have done episodes on any of them, all of which can result in problems if you are deficient. So why vitamin D? It's because vitamin D deficiency has become one of the biggest health problems in the world. According to the World Health Organization, the number of people globally who suffer from some degree of vitamin D deficiency may be as high as a billion people. And other estimates put the number

Starting point is 00:07:33 at double that. Almost everything in the modern world, it seems, is designed to reduce our levels of vitamin D. The biggest culprit, by far, is the fact that people spend more time indoors and not enough time outdoors. Vitamin D deficiency is starting to appear in places with lots of sunlight. Doctors in Kuwait recently warned that vitamin D deficiency was becoming a problem. Cyprus, Greece, and Australia, all sunny countries have seen increased rates of vitamin D deficiency. Air conditioning and white-collar jobs keep people indoors during the day when our ancestors would have been outside working. Video games and computers keep kids inside when they would otherwise be outdoors playing. However, there are other contributing factors as well.

Starting point is 00:08:16 Some pharmaceutical products can block the effectiveness of vitamin D. Obesity can result in an increased need in the amount of vitamin D. People are eating foods with less vitamin D, and many of the foods we do eat, such as factory-produced eggs, chicken, and salmon have less vitamin D than more natural variants. When people go outside, they will often cover themselves in sunscreen which blocks UVB rays, which are responsible for the production of vitamin D. Some researchers have suggested that increasing levels of vitamin D might be the single easiest thing we can do to improve health across the board for the entire human population. So what can you do?

Starting point is 00:08:53 The simple answer is to get outside more often. That's it. So how much sun exposure do you need to create adequate levels of vitamin D? and there is no single answer to that question because there are a host of variables involved. The time of day you're outside, the time of year, the latitude you live at, the amount of skin exposed, and how dark your skin is, all factor in to how much exposure you need. For most people, in most latitudes, the amount of exposure you need each day probably doesn't have to be more than 10 to 20 minutes. This is a level of exposure that was trivial for our recent ancestors, but is actually a problem for many people today. Personally, I was talking to a friend of mine a few years ago who lived in New York City.

Starting point is 00:09:34 She said she went to a doctor and was diagnosed with vitamin D deficiency. As she described her symptoms of feeling sluggish, tired, and sore, I realized that I suffered from many of those things. I set myself on a course of consuming more foods rich in vitamin D and making it a point to take a walk outside every day. The treatment was incredibly simple, but the results were dramatic. Vitamin D deficiency affects a large number of people around the world, and statistically speaking, many of you listening to this podcast right now probably suffer from it.

Starting point is 00:10:03 Thankfully, the solution to the problem is really easy and requires no prescriptions. Just go outside and get yourself some sun. The executive producer of Everything Everywhere Daily is Charles Daniel. The associate producers are Thor Thompson and Peter Bennett. I just want to thank everyone, including the show's producers, who support the show over on Patreon. If you'd like to support the show, just head over to patreon.com, which is currently the only place where you can get show merchandise.

Starting point is 00:10:31 Also, if you want to talk to other listeners about the show, head over to our Facebook group or Discord server, both of which have links in the show notes.

Everything Everywhere Daily: History, Science, Geography & More - Vitamin D

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