Vitamin B12, or cobalamin for those who want to sound fancy, is basically a water-soluble vitamin that’s pretty crucial for your body’s metabolism. It’s part of the B vitamin gang, and animals, including us humans, need it to keep our DNA synthesis on track and to manage both fatty acid and amino acid metabolism. Without it, our nervous system would be a mess thanks to its role in making myelin, and our blood would probably be doing some pretty weird stuff since it’s vital for pumping out mature red blood cells. Plants, on the other hand, couldn’t care less about cobalamin; they do their thing without it just fine.
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Let’s get one thing straight: Vitamin B12 is the most complicated of all the vitamins, and you’re not going to get it from your kale smoothie. It comes from animals, period. Some microorganisms can whip it up, but unless you’re planning on dining on bacteria and archaea, you’re stuck with animal sources or popping supplements. If you’re not eating enough meat, liver, fish, eggs, or dairy, and you’re not into fortified cereals, you’re probably going to end up B12 deficient, especially if you’re vegan, broke, or just trying to live ethically. For those falling short, there are pills and shots to help you out.
Not to scare you, but B12 deficiency isn’t a joke, especially for pregnant women, kids, and the elderly. It’s a bigger issue in places where people aren’t getting enough to eat. In the so-called developed world, the main problem is that some folks’ bodies just can’t absorb B12 properly because they’re missing a crucial stomach component or their stomach acid is MIA, often thanks to age or antacids. Vegans and vegetarians, take note: your diet might not cut it unless you’re supplementing. Lack of B12 can mess you up in numerous ways, from making you tired and dumb to messing with your vision and even causing permanent nerve damage. Pregnant women need to be extra careful since a deficiency can harm their babies big time.
Oh, and the reason we know about Vitamin B12 at all is thanks to a nasty condition called pernicious anemia, which is basically your body’s own immune system wrecking your ability to make enough healthy red blood cells because you’re running low on B12. And guess what? The older you get, particularly past 60, the harder it is for your body to grab onto that B12 and put it to good use.
B12 – A Powerhouse
Vitamin B12 is essentially a cobalt-packed compound sitting pretty in a corrin ring, hitched to a benzimidazole and an adenosyl group. A bunch of its cousins show up to the party, all claiming vitamin status under the family name “cobalamins.” These molecules are pretty much clones in terms of structure and all strut around flaunting their vitamin prowess in systems starved of vitamins, dubbing themselves vitamers. What makes them special? They’re essential for certain enzyme reactions to happen – no B12, no action.
- adenosylcobalamin
- cyanocobalamin, swaps out the adenosyl plus-one for a cyanide.
- hydroxocobalamin, ditches adenosyl for a hydroxide tag-along.
- methylcobalamin, trades in adenosyl for a methyl group.
Cyanocobalamin is basically B12 on steroids, cooked up in a lab. Some bacteria get busy fermenting to crank out AdoB12 and MeB12, which then get a cyanide makeover in a concoction of potassium cyanide, sodium nitrite, and heat to transform into cyanocobalamin. Eat this, and your body flips it back into the AdoB12 and MeB12 forms it actually uses. The two MVP forms of B12 in your body are methylcobalamin doing its thing in the cytosol and adenosylcobalamin in the mitochondria.
Why is cyanocobalamin everywhere in supplements and food fortification? Because cyanide, of all things, keeps it from falling apart. Methylcobalamin is also up for grabs as a supplement, but don’t be fooled – popping adenosylcobalamin or methylcobalamin isn’t going to give you an edge in beating B12 deficiency.
Got a B12 shortfall? Hydroxocobalamin shots straight into the muscle can sort you out. Or, if you’ve gone and poisoned yourself with cyanide, a quick IV can switch the hydroxyl for cyanide, turning it into a harmless version of cyanocobalamin your body can just pee out.
And here’s a kicker: “Pseudovitamin B12” is the poser of the vitamin world, found in truckloads in spirulina. It looks the part but has zero vitamin game, making those claims about its B12 benefits a load of hot air.
Lack of vitamin B12
If you’re running low on Vitamin B12, brace yourself. It’s not just about feeling a bit off; we’re talking serious, possibly permanent screw-ups to your brain and nerves. Even slightly low levels can mess you up: fatigue, dizziness, gasping for air, headaches that won’t quit, mouth sores, a rebellious stomach, not wanting to eat, clumsy walking, weak muscles, feeling downright depressed, memory like a sieve, sluggish reflexes, confusion, skin so pale you’d scare a ghost, and a bunch of other bizarre feelings. People over 60, listen up, because you’re in the danger zone. Oh, and it can also throw you into mania or psychosis. As if that wasn’t enough, expect your immune system to bail, fertility to drop, and your blood circulation to get weird if you’re a woman.
Ever heard of pernicious anemia? It’s the poster child for B12 deficiency anemia, with a nasty trio of symptoms:
- Blood-making gone haywire (thanks to messed up DNA synthesis).
- Gut problems like you wouldn’t believe: from mild toilet dramas to losing control over your bladder or bowels, all because your DNA synthesis is in the toilet, affecting cell turnover. And if your stomach’s getting attacked from within, say hello to ‘watermelon stomach’ alongside pernicious anemia.
- Neurological nightmares: missing reflexes, can’t feel vibrations or a soft touch properly, and your spinal cord starting to degenerate. Kids suffer too – delays, regression, getting easily annoyed, random movements, and muscle tone taking a vacation.
What’s behind this horror show? Mostly your body failing to absorb B12, but also not eating enough of it, your immune system attacking your stomach, not having enough binding proteins, or certain meds. Vegans, pay attention: you’re at risk because plants don’t cut it for B12. Vegetarians, you’re not off the hook either. A shocking 40% to 80% of you aren’t getting enough B12, and don’t get me started on Hong Kong and India’s vegans – about 80% are deficient. Aging doesn’t help, as your stomach acid decides to retire early, messing up absorption even more.
Going overboard with nitrous oxide? Congrats, you’re turning the active B12 in your body into a do-nothing version.
Expecting, Breastfeeding, and the Little Ones
The U.S. thinks you need 2.6 μg/d when you’re pregnant and 2.8 μg/d when breastfeeding, but Europe’s like, “Nope, you need more” – 4.5 μg/d and 5.0 μg/d, respectively. Skimp on B12, and you’re flirting with miscarriage, early birth, and your newborn not weighing enough. Moms-to-be need B12 more than ever because that’s what gets to the baby and breast milk, not what’s stored in your liver. Veggie moms or those not big on animal products, you’re in the danger zone of running low on B12, risking anemia and a B12-deprived infant. Poor diets mean poor B12 levels in breast milk, which is a disaster for breastfeeding beyond six months without introducing B12-rich foods to the baby. Signs your kid is running low include anemia, stunted growth, and developmental delays. Caught early, shots and then oral supplements can turn things around.
After Gastric Bypass: A B12 Nightmare
Getting gastric bypass, specifically the Roux-en-Y type? Welcome to a high-risk group for B12 deficiency. You’ll need shots or massive oral doses to keep from becoming deficient.
Diagnosing This Mess
Good luck finding a definitive test for B12 deficiency. It’s a guessing game involving your symptoms and some blood work that’s as reliable as a weather forecast. Anemia with oversized red blood cells is a red flag. Your B12 blood level is a clue, but it’s not foolproof since your serum can lie, pretending everything’s fine while your tissues are in trouble. Elevated homocysteine and methylmalonic acid levels in your blood might point towards a deficiency, but don’t bet the farm on it, as they can be off for other reasons too. If your nervous system’s taking a hit and blood tests are as clear as mud, they might poke into your spine to check B12 levels there.
B12 Shots and Cyanide – Yes, really!
Kicking B12 Deficiency to the Curb
Got a nasty B12 deficiency gnawing at your health? Brace yourself for a barrage of needle jabs. We’re talking about getting shot up with hefty doses of vitamin B12 right into your muscles, and not just once, but repeatedly, until you’re not teetering on the edge of collapse. Over in the UK, they don’t mess around – you’re getting a 1000 μg hydroxocobalamin injection straight into your muscle thrice a week for two weeks straight, or until your brain fog and other nerve-wracking symptoms decide to take a hike. And after they’ve beaten your deficiency into submission? You’re on a maintenance drip of jabs or pills, though less frequently. But hey, it’s not a walk in the park. Expect to possibly deal with annoying skin rashes, the urge to scratch your skin off, feeling either too cold or too hot, sudden fevers, embarrassing hot flushes, the urge to hurl, and your head spinning like you’re drunk – but without any of the fun.
When You’ve Been Poisoned with Cyanide
So you’ve had a close encounter with cyanide, the stuff of spy novels and murder mysteries? The antidote isn’t some fancy, high-tech gadget but a whopping dose of hydroxocobalamin shoved into your veins, sometimes playing tag-team with sodium thiosulfate. Here’s the deal: the hydroxocobalamin hooks up with the deadly cyanide floating in your body, kicking it out of the toxic relationship and forming something you can pee out without dropping dead. Simple chemistry saving your life, if you get to it in time.
Get Real About B12
Look, it’s pretty simple. Despite all the studies floating around, a good chunk of folks in the US and UK might not be getting enough B12. We’re talking up to 40% of people walking around with less than stellar B12 levels. So, we’ve got grain foods getting a B12 boost to help out. You can pop a B12 pill or get a shot straight to the muscle if you’re running low. Vegans, you’re in a tight spot since plants don’t do B12, meaning you better be chowing down on supplements or fortified foods unless you fancy risking your health. And don’t even get me started on kids in developing countries – they’re in a real bind with their growth needs and not enough animal foods in their diets.
The US National Academy of Medicine finally got around to updating their B12 guidelines in 1998, setting the bar at 2.0 μg/day for adults, with a bit more during pregnancy and lactation, because, you know, growing a human inside you demands more. They tossed in a bit more for kids and the elderly, especially since a good 10 to 30% of older adults can’t absorb B12 from food like they used to. They didn’t bother setting an upper limit for B12 intake because, apparently, you can’t OD on it.
Over in Europe, they’re a bit more generous with their B12 numbers, throwing around higher daily amounts because why not? No upper limit there either – seems like everyone agrees on the “can’t have too much of a good thing” philosophy when it comes to B12.
Japan and the World Health Organization are on the 2.4 μg/day bandwagon, keeping things consistent internationally. And for those obsessed with food labels in the US, the government did a switcheroo on the daily value percentage, dropping it from 6.0 μg to 2.4 μg, because they figured out that’s really all you need. Manufacturers had to update their labels by 2020 or 2021, depending on how big of a deal they are in the food game. There’s even a handy table showing the old vs. new values, for anyone who cares.
Breaking it Down
The Microbial Factory
Here’s the deal: Vitamin B12? It’s all thanks to bacteria and their archaea buddies. Humans have these bacteria doing their thing in our guts, but we’ve been under the impression that we can’t use the B12 they make because it’s produced too far down the digestive highway, beyond where we usually pick up our nutritional hitchhikers. Meanwhile, animals like cows and sheep have their digestive systems set up like a pre-dinner party where microbes get to work on the food before it hits the stomach proper, allowing these animals to snag that B12. Then there’s a bunch of other critters like rabbits and guinea pigs that basically eat their own processed food (yes, they eat their poop) to grab some of that microbial B12 goodness. And if the animals aren’t getting enough cobalt from their diet, their B12 production tanks and you might have to jab them with B12 shots or cobalt supplements. Talk about high maintenance.
Meat and More
Animals hoard B12 like it’s going out of style, stashing it in their livers and muscles and even passing it into their eggs and milk. So, if you’re not squeamish about where your nutrients come from, chowing down on meat, liver, eggs, and milk is your ticket to B12 central. Fish, poultry, and meat are your best bets, but if you’re into crunching on bugs, they’ve got you covered too. Just so you know, eggs are kinda stingy with B12, so you might want to look elsewhere.
Green Doesn’t Always Mean Go
There’s some chatter about plants and algae stepping up to the B12 plate, but don’t put your money on it. The nutrition experts essentially call it a wild goose chase for vegans, pushing them towards fortified foods and supplements instead. Sure, you’ve got your fermented plants and seaweed snacks that might have some B12, but it’s all second-hand from their bacterial pals. Essentially, plants and algae are middlemen, not producers.
Fortify the Fort
For those who can’t be bothered with all the dietary gymnastics, there’s a whole lineup of B12-fortified foods like cereals and fake milks. They basically sprinkle some cyanocobalamin (fancy B12) into the mix, and voilà, you’ve got your dose. And yeah, a bunch of countries are on this bandwagon, adding B12 to everything from flour to rice. Vegans, take note: this is your easy out.
Pill Popping and Shots
Don’t want to plan your meals around B12? Just pop a pill or catch a shot. You can find B12 supplements pretty much anywhere, and if you’re really into it, you can get jabbed with a dose that’ll keep you running smooth. Oh, and for those worrying about the cyanide in some B12 forms, chill. It’s less than what you’re already getting from your food.
Needles or Not
Got trouble with your guts not taking up B12? Shots might be your best bet, but if you’re not into playing pincushion, high-dose pills might do the trick since a tiny bit gets absorbed anyway. And for the unlucky ones with cobalamin C disease, oral supplements won’t cut it; you’re looking at shots or skin patches.
Future Tech
The current ways of getting B12 into your system are so last century. Scientists are cooking up nanotech to get B12 right where it needs to go, aiming to ditch needles, cut costs, and basically make life easier for everyone involved.
Watch Out for Fakes
Last but not least, not everything that glitters is B12. There’s a bunch of wannabe B12s out there that do squat for your body. They’re called pseudovitamin-B12, and they’re pretty much a bad joke played by nature. Oh, and then there’s antivitamin B12 – actual B12 saboteurs designed to mess with its actions. Just when you thought it was safe to go back in the water, right?
Drug Interactions
H2-Receptor Blockers and Proton-Pump Inhibitors: Gut Saboteurs
Listen up, here’s the lowdown: You need stomach acid to free vitamin B12 from the shackles of protein so your body can absorb it. Pop an H2 blocker or a proton-pump inhibitor (PPI) and you’re essentially telling your stomach to take a hike, slashing its acid production. This messes with how much protein-bound vitamin B12 you can snag from your grub, though, weirdly enough, B12 pills dodge this bullet. Got a lineup of usual suspects for H2 blockers like cimetidine and ranitidine, and for PPIs, think omeprazole and its buddies. Now, unless you’re guzzling these meds for a couple of years or you’re basically living off air, a vitamin B12 nosedive into deficiency and anemia is a long shot. But, if these drugs turn your stomach into a dead zone with zero acid action—spoiler alert: PPIs are notorious for this—you’re in for a world of vitamin deficiency hurt.
Metformin: The B12 Burglar
Roll the dice with long-term metformin for your sugar woes and you might end up in the 30% club of folks with dwindling B12 levels. But hey, it’s not a death sentence. Keep your B12 munchies up or pop a supplement and you’re golden. Catch the drop early and you can stick with metformin, just arm yourself with some B12 backup.
The Usual Suspects: Other Meds on the Hit List
Some meds are like thieves in the night, sneaking away with your vitamin B12. The culprits? Colchicine, those extended-release potassium pills, and a rogue’s gallery of antibiotics like gentamicin. Seizure meds aren’t saints either, with phenobarbital and friends tanking your B12 levels, except for valproate, which oddly does the opposite. Oh, and get this: certain drugs even mess with your B12 tests, throwing in curveballs like amoxicillin and methotrexate. Watch your back.
Chemistry, Straight Up
Let’s cut to the chase: Vitamin B12 is the big boss of vitamins, complexity-wise. Its backbone, the corrin ring, is like the cousin of the porphyrin ring you find in heme, but with cobalt as the star in the middle. This cobalt isn’t just hanging out; it’s sold as a stable solid and is in the game with a +3 oxidation state in both cyanocobalamin and its vitamin buddies. Biochemically speaking, this cobalt is a bit of a show-off, flipping between +1, +2, and +3 oxidation states, which lets B12 do its magic in the body as both a radical party-starter (donor of deoxyadenosyl radical) and the guy who brings the methyl cation to the table (electrophilic alkyl source). The corrin ring gives a hand with four of the six coordination sites, some dimethylbenzimidazole group steps up for the fifth, and the sixth? It’s the wildcard spot, ready to be anything from a cyano group to a hydroxyl group, a methyl group, or a 5′-deoxyadenosyl group. And let’s not forget, the carbon–cobalt bond in B12 was one of the first of its kind found in biology, paving the way for all sorts of metal–carbon bond shenanigans in enzymes and animals, which can switch up cyanocobalamin and hydroxocobalamin into forms the body actually likes using.
Figuring Out How Much Vitamin B12 Is in Your Food
When it comes to measuring the vitamin B12 in food, it’s been a bit of a wild ride with methods ranging from microbiological assays to high-tech chromatography. For a long time, people relied on microbiological assays, using some picky vitamin B12-dependent microorganisms that could throw tantrums and give iffy results if they stumbled upon any vitamin B12 wannabes in the food. Plus, they took their sweet time, needing a whole night to think things over. These days, that method’s been kicked to the curb in favor of something called the radioisotope dilution assay (RIDA), which teams up with pig guts to figure out the vitamin B12 levels in food. Turns out, RIDA is on point, spotting higher levels of vitamin B12 than the old-school microbiological approach ever could.
Biochemistry: No Sugar-Coating
The Real Deal on Coenzyme B12
Let’s get this straight, Vitamin B12 isn’t just some optional vitamin you can skip like a morning jog. It’s crucial for enzyme reactions in your body. Without it, you’re basically sabotaging your metabolic processes. Here are the enzyme types that are practically begging for B12:
- Isomerases
- These guys shuffle hydrogen atoms around like cards, making sure everything’s in the right place for your body to function. They’re not playing games; they need adoB12 (adenosylcobalamin) to do their job right.
- Methyltransferases
- It’s all about swapping methyl groups between molecules. Think of it as molecular trading, and it’s using MeB12 (methylcobalamin) as currency.
- Dehalogenases
- Then, there’s the environmental cleanup crew – certain anaerobic bacteria with B12-dependent dehalogenases. They’re the unsung heroes breaking down pollutants, but depending on either their own corrinoid factory or an external B12 supply.
In humans, we’re looking at two main B12 lovers in the enzyme family, specifically:
First, Methylmalonyl CoA mutase (MUT), which is vital for breaking down certain amino acids. Without it, and consequently B12, you’re not only messing up energy production but also risking neurological damage due to accumulating neurotoxins. Seriously, vitamin B12 deficiency is not a joke.
Then, there’s Methionine synthase – a fancy term for an enzyme that makes sure homocysteine doesn’t pile up in your system, which can be bad news for your heart and arteries. It keeps the cellular factory running, ensuring new cells, especially the rapidly dividing ones, are produced efficiently. Screw up your B12 intake, and you’re looking at a domino effect of health issues, including messed-up DNA synthesis and potentially severe anemia. But hey, eat your greens, and you might dodge the worst of it thanks to dietary folate. Still, B12 isn’t something you want to skimp on unless you’re keen on a cocktail of health issues.
Bottom line? B12 isn’t optional. It’s essential. Treat it as such.
Physiology Unfiltered
Absorption: The No-Nonsense Breakdown
Alright, here’s the deal: your body snags vitamin B12 from your grub in two main ways. First, there’s this fancy B12-specific setup in your intestines that ropes in 1–2 micrograms every few hours through something called intrinsic factor. This is how you get most of the B12 your body craves. The other method is basically the vitamin slipping through the cracks by passive diffusion. The whole process of grabbing B12 out of your food and into your system is ridiculously complicated. Before B12 can even think about getting absorbed, it has to be cut loose from the proteins in your food, thanks to your digestive juices working overtime in both your stomach and small intestine. And if you’re popping antacids or any of those proton-pump inhibitors like candy, you’re shooting yourself in the foot because they mess with B12 absorption.
After B12 is freed up, it doesn’t get a free pass to your bloodstream. It first has to tango with R-protein spit out by your salivary glands, which is basically a bodyguard protecting it from your stomach’s acid pit. Then, in a move that feels like a weird game of hot potato, B12 ditches R-protein for another partner, intrinsic factor (IF), without which it can’t get through the door into your bloodstream. This whole circus act of binding and rebinding is necessary because your small intestine is picky and only recognizes the B12-IF duo; plus, it keeps the vitamin safe from getting demolished by gut bacteria.
If any part of your gut team is slacking—like your stomach, pancreas, IF production, or small intestine—it could tank your B12 levels. Some unlucky folks can’t make IF because their immune system has gone rogue and attacks their stomach lining or the IF itself, leading to a nasty case of pernicious anemia. Also, if you’re getting on in years, your stomach might not be as acidic as it used to be, putting you at risk for B12 deficiency since you’ll just end up pooping out most of the B12 you take in.
Once B12 and IF finally make it to your small intestine and get recognized, B12 is transferred to a plasma transporter called transcobalamin II (TC-II/B12). But even then, some people can’t use B12 properly because of genetic issues with TC-II or its receptors, which can lead to anemia and messed-up B12 biochemistry, even if they have enough B12 floating around in their blood. And if you think swallowing mountains of B12 pills is going to fix absorption issues, think again. Sure, high doses can bypass some absorption problems, but it’s more like a Band-Aid than a cure.
Storage and Excretion: The Straight Dope
How quickly your body burns through B12 depends on a bunch of factors, like how much you’re eating, secreting, and absorbing. Adults have 2–5 mg of B12 stashed away, with half of it holed up in the liver. You lose a tiny fraction of it daily through your gut since not all of it gets sucked back up. Bile is the main way your body dumps excess B12, but thanks to a slick recycling process, your liver can hoard enough B12 to last 3 to 5 years. So unless your absorption game is off, you’re unlikely to run out of B12 any time soon.
Cellular Reprogramming: B12’s Side Hustle
Turns out, B12 is a bit of a backstage VIP in the cellular world, keeping cells on the straight and narrow and playing a critical part in turning regular cells into pluripotent stem cells. It’s all about one-carbon metabolism, baby. B12 levels can make or break the histone modification game, keeping cells from going rogue on gene expression. In experiments where mice were turned inside out (figuratively speaking) to create stem cells, low B12 levels were a bottleneck, but pumping them full of B12 cranked up the efficiency. So, B12 isn’t just about keeping your blood cells and nerves happy—it’s also a key player in the regeneration game.
Get to the Point
How B12 Comes to Be
Alright, let’s cut through the jargon. Vitamin B12 isn’t some mystical substance; it’s cobbled together from simpler parts, thanks to a couple of enzymes that play with aminolevulinic acid like it’s Lego. These enzymes bash it into porphobilinogen and some other intermediates until it becomes uroporphyrinogen III. This stuff is the building block not just for B12, but also for heme, chlorophyll, and siroheme. Scientists had to tag methyl groups with C-labelled S-adenosyl methionine to track how B12 gets its final form. The real breakthrough came when some brainiacs decided to soup-up a strain of Pseudomonas denitrificans with extra genes, making the whole B12 assembly line visible down to the last bolt.
When it comes to pumping out B12, a bunch of microorganisms are on the job, including Propionibacterium shermanii, Pseudomonas denitrificans, and a whole zoo of others like Streptomyces griseus and Lactobacillus. Basically, if it’s a microbe, chances are it’s in the B12 business.
Mass-Producing the Stuff
On the industrial front, cranking out B12 boils down to fermenting certain microbes. Streptomyces griseus used to be the go-to bug until Pseudomonas denitrificans and Propionibacterium freudenreichii subsp. shermanii stole the spotlight, thanks to some clever tweaking to boost their productivity. One big name in the game, Rhone-Poulenc, even genetically modified P. denitrificans to up the ante. And yes, Propionibacterium is considered safe by the bigwigs at the FDA, so no need to panic about toxins. Back in 2008, the world was churning out 35,000 kg (that’s 77,175 lb for those who hate the metric system) of B12.
Lab Shenanigans
Now, if you think industrial production is wild, the lab synthesis of B12 is just bonkers. Robert Burns Woodward and Albert Eschenmoser are the mad scientists behind it, dragging 91 postdocs and 12 PhD students from around the globe into their scheme back in 1972. They managed to stitch together B12 in 72 steps from cobyric acid, a feat that’s academically impressive but practically useless because of its abysmal yield. Despite this, no one else has bothered to find a better way since, making their method the only game in town for those wanting to make B12 from scratch in a lab.
History
Old-Timey Scientists Scribbling Down Notes About Anemia
Let’s kick it off between 1849 and 1887, where Thomas Addison wasn’t just chilling; he was busy calling out pernicious anemia. Then William Osler and William Gardner basically stumbled upon neuropathy like it was nothing. Hayem spotted these oversized red cells and dubbed them “giant blood corpuscles” (yeah, we’re talking about macrocytes), while Paul Ehrlich was playing detective with megaloblasts in the bone marrow. And Ludwig Lichtheim? He threw down the gauntlet with a case of myelopathy.
Liver: The Unexpected Hero of Anemia
In the roaring ’20s, George Whipple was throwing raw liver at dogs like it was going out of style, noticing it fixed their anemia pretty darn fast. He made the leap that maybe, just maybe, liver could be the magic bullet for pernicious anemia. Enter Edwin Cohn, who cranked up liver’s anemia-fighting power by a factor of 50 to 100. William Castle wasn’t about to be left out, showing that some mysterious “intrinsic factor” in gastric juice, when mixed with meat, helped absorb the essential vitamin. In 1934, George Whipple, alongside William P. Murphy and George Minot, snagged the Nobel Prize for figuring out liver could treat pernicious anemia, thanks to its hefty dose of vitamin B12.
Cracking the Vitamin B12 Code
Mary Shaw Shorb wasn’t just messing around with yogurt bacteria for the fun of it. When she connected the dots that liver extract (a life-saver for pernicious anemia victims like her late father-in-law) was needed for her bacteria, she smelled an opportunity. With a bit of cash from Merck and some brainpower from Karl Folkers, they used her bacteria to hunt down the “LLD factor,” a.k.a. the key to the bacteria’s happy life. Fast forward, and with Alexander R. Todd’s help, they purified this stuff and crowned it vitamin B12. Dorothy Hodgkin then went full Sherlock Holmes on its structure, bagging herself a Nobel Prize in Chemistry in 1964 for this and other work.
Oh, and let’s not forget George Whipple, George Minot, and William Murphy, who were probably toasting with liver smoothies in 1934 with their Nobel Prize. Then Alexander R. Todd (1957), Dorothy Hodgkin (1964), and Robert Burns Woodward (1965) joined the Nobel club for their vitamin B12 fan club contributions.
Turning B12 Into Big Business
These days, cranking out vitamin B12 is all about getting the right microbes drunk on sugar in giant vats – a far cry from squeezing livers. Despite Robert Burns Woodward and Albert Eschenmoser pulling off a lab synthesis of B12 in 1972, with an absurd 70+ steps and a yield that’s laughably low, nobody’s rushing to turn that method into a cash cow.
Society and culture’s weird obsession
In the ’70s, this Baltimore doc, John A. Myers, thought it was a bright idea to start pumping people full of vitamins and minerals straight into their veins for pretty much anything that ailed them. He whipped up this concoction he dubbed the Myers’ cocktail, chucking in 1000 μg of cyanocobalamin for good measure. Fast forward past Myers’ demise in ’84, and you’ve got a bunch of other doctors and so-called naturopaths jumping on the bandwagon, pushing this “intravenous micro-nutrient therapy” as some miracle cure for everything from being tired or stressed to shedding a few pounds. Spoiler alert: despite their grand claims, there’s zilch in terms of hard science backing this up. Yet, that hasn’t stopped some health “professionals” at clinics and spas from shoving needles filled with this stuff into people’s arms, or even just sticking them with vitamin B12 shots for a quick buck. The Mayo Clinic even chimed in, basically calling BS on the whole vitamin B12 energy boost and weight loss angle.
Oh, and it turns out doctors are especially keen on jabbing elderly folks with cyanocobalamin injections, often without any legit reason. A hefty study showed a bunch of these patients either didn’t need it because their levels were fine, or no one even bothered to check first. Talk about shooting in the dark.