#18. The Silent Pandemic

Over 70% of the U.S. population has either a deficiency or insufficiency in vitamin D.

Jun 18, 2025

I’ve noticed a troubling pattern in the hundreds of patients I see every week.

Most are office workers or people who spend all day indoors. They complain about chronic back pain. They look tired and hollowed out. Their moods are low. They fall sick often. And a surprising number have blood tests showing low levels of Vitamin D3, the active form of the steroid hormone our skin synthesizes from the sun.

This isn’t a random finding. It lines up with data showing that over 70% of the U.S. population has either a deficiency or insufficiency in vitamin D. And no, it’s not just a Western problem. It’s global. Even in countries with sun exposure all year round. Why?

Because the risk factors for deficiency have embedded themselves into our modern lives. We work in buildings. Commute in vehicles instead of walking. Spend most weekends indoors and only go out at night. Our skin is often covered—by long sleeves, sunscreen, or just the default of always being in a shade. We also live in places where the sun isn’t strong enough during parts of the year.

Last week, I realized I wasn’t immune to this overlooked pandemic either. I was hit hard by a brutal flu—headache, joint pain, fever, malaise. I realized I might also be low on vitamin D. I work indoors all day, and when I get time to be outside, I’m usually in a shade. My mentor suggested a protocol: 60,000 IU of vitamin D3 once a week, paired with magnesium, Vitamin C and zinc. I swallowed the vitamin D3 capsule with a healthy high fat lunch, as I had seen recommended, not expecting much.

But an hour later, something changed. The joint pain and malaise had receded. My body stopped aching. The fever went away. And the headache was non-existent. Just like that. But what shocked me most was how alive I felt—mentally lucid, lively and emotionally uplifted. It felt like I’d swallowed the sun. I felt powerful. Grounded. Alert. Like someone had cleared the cache.

Two days later, I felt better than I did even before the illness. I was sleeping well and waking up happy. I was more assertive. My gym performance was more explosive, made onlookers awe at my vivacity. I was lighter in spirit, more confident, a bit curt and more eager to take risks.

This change was so canonical, it bugged me enough to research and correlate my findings to objective parameters. I had to understand why.

What I learned is that vitamin D doesn’t just strengthen your bones. The active form regulates over 900 genes, affecting your brain (optimizing cognitive performance and reducing brain damage in diseases like ADHD, Autism, bipolar disorder, anxiety and Dementia), impacts muscle growth, influences immune cell activation, and modulates inflammation. It also supports hormones like dopamine, serotonin, and testosterone (due to presence of Vitamin D receptors in Leydig cells), which affect your mood, memory, libido, energy & drive, your executive function, your ability to delay gratification, plan on a long term scale and feel content. Basically, everything we need to live well, endure and thrive. If your vitamin D levels are low, these systems don’t work as well, and you feel it everywhere.

Here’s what makes things worse.

Obesity acts like a trap—it leads to the storage of vitamin D in fat, where your body can't use it to regulate all those processes we’ve talked about. Darker skin synthesizes less under the same sun, requiring longer sun exposure for adequate effect. Older adults make up to 75% less vitamin D through their skin than when they were young. Kidney and liver dysfunction slow activation. Gut damage and dysfunction impairs absorption. Common meds like nifedipine, rifampin, and antifungals accelerate its breakdown. Even breastfed infants are at risk if their mothers aren't supplementing properly.

So this is what I recommend:

Get your serum 25(OH)D tested to establish baseline status. Optimal functional range is generally 40–60 ng/mL. Values below 30 ng/mL reflect insufficiency; <20 ng/mL constitutes clinical deficiency.
Get judicious sunlight exposure, direct and unimpeded by glass, sunscreen, or clothing, during peak UVB availability from noon to 1400hrs. Aim for 15–30 minutes, several times weekly, depending on skin phototype and latitude. However, most people don't get nearly enough. And let’s be honest, some of us barely have the time. In that case,
Start oral supplementation as necessary: 5,000 IU daily or 60,000 IU weekly of cholecalciferol (D3), co-administered with a healthy fatty meal to enhance micellar absorption. Get your supplements from quality and reputable sources.
Add co-factors: magnesium (400 mg) and zinc (50 mg) to facilitate enzymatic hydroxylation, and vitamin K2 (preferably MK-7) to regulate calcium deposition and prevent vascular calcification. K2 sources include butter, liver, fermented foods, and supplements.
Monitor levels over time when supplementing. Although toxicity is rare, sustained concentrations >100 ng/mL may carry risk. Avoid bolus megadosing outside clinical supervision.
Lastly, obviously lose weight, get fit and fix your gut. I’ve written extensively about all that.

Note that vitamin D optimization is not a panacea, but deficiency handicaps virtually every systemic axis. Err on the safe side. Restoring sufficiency reboots your entire biological operating system reconstituting cellular competence and systemic vigor. The effects I experienced were far from psychosomatic artifacts, they were the physiological consequences of reestablishing hormonal equilibrium and transcriptional regulation.

As always, consult your doctor before use. This is not medical advice.

Here are the peer-reviewed research studies that supported my findings:

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