Working as a physician and medical director in post-acute and long-term care, I’ve seen how easy it is to miss vitamin deficiencies that have real clinical impact. Many of our residents have age-related malabsorption, multiple comorbidities, and limited diets; add polypharmacy and functional decline, and the risk grows. Over the past few years, I’ve started screening vitamin D and B vitamins in residents with frailty, falls, anemia, cognitive decline, or nonspecific fatigue — and I’ve been surprised by how often this changes care. I’ve found vitamin D deficiency in the majority of residents I check, and more vitamin B6 deficiency than I expected, even in those who looked nutritionally stable on the surface.

My approach is practical and individualized. When a long-term care resident presents with functional decline, anemia, or new neuropsychiatric symptoms, I typically check vitamin D, B12, and B6 levels. If B12 levels return borderline (200–400 pg/mL), I sometimes order methylmalonic acid (MMA) to confirm true deficiency. MMA is the most specific marker for low B12 activity, but I use it selectively because it hasn’t been proven to change long-term outcomes compared with simply treating empirically — and treatment is safe and inexpensive. Homocysteine, on the other hand, is less useful in this population; it’s nonspecific, affected by renal function, and rarely changes management. For residents with poor intake, chronic wounds, or recurrent infections, I sometimes add vitamin C, but I avoid broad panels unless there’s a strong clinical reason. This targeted strategy ensures that care is both clinically meaningful and cost-conscious.

I always document my reasoning, which also reassures surveyors: “Resident with recurrent falls and chronic fatigue — checking vitamin D and B vitamin panel to rule out deficiency contributing to weakness.” Or: “Patient with macrocytic anemia — B6 level low; supplementation started and will be reassessed in 8 weeks.” This kind of clarity shows thoughtful, patient-centered medicine rather than reflexive ordering. Paying attention to these silent deficiencies can prevent avoidable frailty, weakness, and cognitive decline while keeping care survey-ready and evidence-based — a small but impactful intervention in a complex population.