Overly responsible for everyone else from a young age. Parentified even. Dependable to the point of invisibility. If you’re a Swifty, you know where this is headed, but for the rest of us: welcome to Eldest-daughter Syndrome and, strangely enough, to the story of Thiamine. It’s the number 1 in B1, right, that unambiguously announces the arrival of nutrition’s firstborn to the world. Isolated & identified as essential to humans in 1926, she’s undeniably our eldest and yes, she’s turning 100! But before we get her to blow out the candles, just like Tay Tay, she has a few spicy words she’d like to share on what being the often-ignored eldest has entailed, especially in the context of our long-standing carb culture wars!

But, first she’d like to set the record straight regarding her siblings.

“We’re not related – you know – me & all those that came afterwards, like B2, 3, 5, 6 etc.?!
Our names make it sound like each new ‘B’ baby was just a small shift in chemical structure from the last! But nothing could be further from the truth! Have you seen any snaps of us all side by side?! We look nothing alike!
[ignore the artist’s impression above!]
Other than occasionally crossing paths on a job, there’s nothing more meaty or meaningful that connects us!”

And it’s true of course, the numbers merely reflect the chronology of their discovery. And what about all the missing ones like B4 & B8? These were micronutrient miscarriages, of a kind. For example, we thought they were essential, but then we identified endogenous production, only much later to acknowledge not enough, as was the case with choline (B4). But by this time, Nutritional Science had conceded the complete folly of such a simplified naming system, acknowledging that the ‘B vitamin family’ was in reality more of a biochemical ‘junk drawer’ rather than a coherent collective but misunderstandings about this persist! ‘Why is she so keen to separate herself from her siblings?‘, you might be wondering, well listen in…

“Because I mostly work alone. Well except for my one true metabolic mate: Magnesium. Whom without, I can’t get a thing done! And what’s most crazy about us two is twofold! We’re both central to energy supply – especially in the form of carbohydrates – yet diets at either end of the carbohydrate intake spectrum (LCDs, grain-free, Keto, Carnivore OR SAD) are equally at risk of our inadequate intake!
So if you know who’s behind these carb culture wars – I’d like to have a word!”

But if this was the case, wouldn’t you be seeing B1 deficiencies in your patients? Look again. Our whole understanding of its deficiency picture has undergone a complete rethink. One of my favourite articles on this, that has stayed with since I first read it in 2021, calls this out from the kick-off: Hiding in Plain Sight – Modern Thiamine Deficiency. But there’s SO much more that has emerged even since then! Have you met the new baby of the Beri Beri family? Remember the wet (CVS) and the dry (Neuro) presentations & forms? Well now there’s a third, plus a whole subclinical syndrome that we’re absolutely seeing! And sometimes in our so-called ‘healthiest’. Should we just dose everyone with the ‘biochemical junk drawer’…ummm, no. Yeah…our ideas on how to support B1 status are also in need of an entire overhaul! While I’m sure you’d love to hear about this from our eldest herself, it’s been another big day in a big birthday year, and never one to say no to carbs and especially cake when it’s full of B1 fortified flour(!) she’s a bit sleepy now…so you might just need to listen to my 30 min summary of all the absolute must-knows instead!

Photo by Fylkesarkivet i Vestland on Unsplash

B1 Caught in the Crosshairs of Our Carb Culture Wars

For a vitamin discovered through catastrophic deficiency disease, thiamine (Vitamin B1) has become strangely invisible in modern health conversations. And yet, quietly and relentlessly, it sits at the gateway of carbohydrate metabolism itself. In this episode, Rachel revisits one of nutrition science’s oldest discoveries through an unmistakably contemporary lens – exploring how modern eating patterns may simultaneously increase our dependency on B1 while reducing the likelihood of obtaining enough of it.

From ultra-processed diets and alcohol intake to grain-free eating patterns, obesity, bariatric surgery, and the rise of GLP-1 medications, this episode examines why thiamine may be uniquely vulnerable in the modern metabolic landscape.

This is not an episode about demonising carbohydrates, glorifying low-carb diets, or promoting simplistic supplement narratives. It’s an exploration of metabolic context, nutritional trade-offs, and the hidden micronutrient costs embedded within contemporary food culture. Or, put more simply: the story of a tiny vitamin carrying a disproportionately heavy load.