🕰️ My first 2-parter 3-parter blog: The Lie About Vitamin D – Intake, Bioavailability, Magnesium, and K2 – PART 3

• Part 1 will focus on the time change, lack of movement, spinal effects, and the introduction of vitamin D as the next topic — ending with a “Stay tuned for Part 2.”
• Part 2 will dive into vitamin D deficiency, symptoms, new calcifediol research, and its impact on the spine and nerves, continuing the same conversational tone.
• Part 3 (I lied.  I said it was going to be a 2-parter, but it’s like going down a rabbit hole, like staring at a train wreck, like… well, whatever else analogy that revolves around not being able to stop one’s self from continuing.) will fact-check old government stats and educate you on new research.

Your Parents Lied To You

If your parents told you eating spinach makes you strong, they owe you an apology…  So does the US Government… So does Popeye (except 90% of my readers have no idea what is a Popeye… I’ll give you a hint… it’s a Who… not a What)

There are very few things we all share as a collective childhood memory. Riding bikes without helmets. Drinking milk because it “built strong bones.” And, of course, being told to eat our spinach because look how strong Popeye gets when he eats spinach. I still remember the cartoon.

What no one told us at the time was that Popeye’s superpower didn’t come from spinach. It came from ONE PERSON putting a decimal point in the wrong place.

Spinach, as it turns out, never contained the heroic amount of iron it was credited with for decades. The original nutritional tables overstated its iron content by roughly tenfold, a mistake that propagated through textbooks, public health messaging, and eventually cartoons. Even worse, what little iron spinach does contain is poorly absorbed due to compounds called oxalates, which bind iron and make it less usable by the body.

In other words, Popeye didn’t need more spinach. He needed better statistics.

Which brings me, oddly enough, to Vitamin D.

Medical Statistics, Simplified Messages, and How Errors Live Longer Than Facts

The spinach myth is a useful reminder that medicine doesn’t usually get things wrong out of malice. It gets things wrong out of oversimplification. Numbers are interpreted. Averages are mistaken for guarantees. Messages are reduced so they fit on posters, cereal boxes, or morning talk shows.

And once those messages settle into the public consciousness, they are very hard to uproot—even after the science evolves.

Fast forward nearly a century from Popeye, and we find ourselves in a remarkably similar situation with Vitamin D.

The Vitamin D “Blunder”: What Actually Went Wrong

Vitamin D has been studied extensively. The issue isn’t that researchers didn’t look closely enough. It’s that the way the data was translated into public recommendations relied too heavily on averages.

In simple terms, early models used population averages to determine how much Vitamin D intake was required to reach a target blood level. But averages don’t protect most people—they protect some people. When statisticians revisited this approach in the mid-2010s, they pointed out a critical flaw: if you want nearly everyone to reach adequate Vitamin D levels, you need to account for variability in absorption, metabolism, body composition, and baseline status.

When those factors were properly modeled, the amount of Vitamin D intake required to ensure sufficiency for almost everyone was dramatically higher than the established recommendations.

This wasn’t fringe science. It wasn’t a conspiracy. It was a correction. And by 2017, the issue was being openly discussed in academic literature as a major statistical misinterpretation.

Yet here we are, years later, and the public message remains largely unchanged: “Just take some Vitamin D.”

Data & Photo Credit: https://pmc.ncbi.nlm.nih.gov/articles/PMC4210929/

Why the Message Never Quite Caught Up

Scientific corrections move slowly. Guidelines move slower. And public messaging moves slowest of all.

Doctors are busy. Patients want clear answers. Institutions prefer conservative guidance. So the nuance gets lost. The headline survives, but the context doesn’t.

Which brings us to the next layer of the Vitamin D conversation—one that’s rarely discussed outside clinical circles.

Vitamin D Intake Is Not the Same as Vitamin D Effectiveness

Vitamin D is fat-soluble. That means it behaves very differently than, say, Vitamin C. It requires proper digestion, transport, and enzymatic conversion to become active in the body.

And this is where two critical cofactors enter the conversation: magnesium and vitamin K2.

Magnesium plays a role in the enzymatic steps that convert Vitamin D into its circulating and active forms. When magnesium status is low—which is surprisingly common—Vitamin D supplementation may not produce the expected rise in blood levels or clinical effects. In some cases, people take Vitamin D faithfully and still remain deficient because the machinery required to activate it is underpowered.

Vitamin K2 enters the discussion not because it increases Vitamin D absorption, but because it influences how calcium is handled once Vitamin D increases calcium uptake. K2-dependent proteins help direct calcium toward bones and away from soft tissues. This relationship is biologically plausible and clinically relevant in certain contexts, though it is not a universal requirement for everyone taking Vitamin D.

The key point is this: Vitamin D does not act alone. It operates within a system. And systems fail when one component is missing.

Why This Matters Clinically—Not Just Academically

At Neurolink Chiropractic, we don’t treat lab values. We treat people.

And when Vitamin D status is low, we often see patterns emerge: increased inflammation, muscle weakness, heightened nerve sensitivity, slower recovery, and greater susceptibility to seasonal symptom flares. These issues don’t live in isolation. They intersect with spinal mechanics, nerve compression, circulation, and movement.

This is especially relevant for patients dealing with peripheral neuropathy, chronic pain, or recurrent winter-related flare-ups. Low Vitamin D doesn’t cause these conditions outright—but it can absolutely lower the body’s resilience and amplify symptoms.

That’s why supplementation alone is never the full answer.

Where Neurolink’s Approach Fits In

Nutrition matters. But biomechanics matter too.

Spinal decompression addresses mechanical nerve irritation that no supplement can fix. Chiropractic adjustments restore motion that circulation depends on. Vibration platforms help stimulate blood flow and neuromuscular activation, particularly in patients whose extremities are cold, stiff, or neurologically underperforming.

These therapies don’t replace nutrition—they complement it.

Because health isn’t achieved through a pill. It’s achieved through alignment, movement, circulation, and support.

The Real Lesson (Spinach Was Just the Opening Act)

Spinach wasn’t the villain. Vitamin D isn’t the villain either.

The real issue is how easily simplified messages outlive nuanced science.

We didn’t need less spinach. We needed better data. We don’t need less Vitamin D. We need better context.

Medicine improves when we allow it to evolve—and when we resist the temptation to reduce complex systems into one-line solutions.

A Smarter Way Forward

If you’ve been told Vitamin D “doesn’t work for you,” it may not be the Vitamin D.
If you’ve been taking supplements without improvement, the issue may not be compliance.
And if winter seems to expose weaknesses you didn’t know you had, that’s not coincidence—it’s physiology.

This season is an opportunity for you to discover those ailments that were otherwise asymptomatic.

And once you understand why they surface, you can begin addressing them intelligently.

Call to Action

At Neurolink Chiropractic, we take a systems-based approach to health—addressing the nervous system, spinal mechanics, circulation, and supportive therapies that allow your body to function at its best.

If you’re dealing with chronic pain, neuropathy symptoms, or seasonal flare-ups that don’t make sense on paper, it may be time for a deeper conversation.

Your parents may owe you an apology about spinach.
But your body deserves better information going into the winter season about best ways to take Vitamin D.

This page is for informational purposes only and does not provide medical advice. Before starting any diet or supplements, discuss your plans with your medical doctor and ask about ordering the appropriate laboratory tests first.