Vitamin D Toxicity Induced by Social Media-Driven Supplementation: A Case Report on the Dangers of Medical Misinformation

Authors

Spencer D. Thatcher, Abu-Bakr Ahmed, Misti Song, MD, Nicolas B. Alvarado, MD

Introduction

Vitamin D supplementation is widely used for bone health and general wellness, particularly among older adults. While deficiency is common, excessive intake can lead to hypervitaminosis D, a rare but potentially life-threatening condition characterized by parathyroid hormone–independent hypercalcemia. In recent years, the rise of social media as a source of health information has contributed to unsafe supplementation practices, with nonmedical influencers promoting high dose or “megadose” vitamin regimens without clinical oversight. These practices pose particular risk to elderly patients, who may be more susceptible to the metabolic consequences of excess vitamin D. This case describes severe vitamin D toxicity presenting with hypercalcemia in an elderly woman, directly linked to excessive supplementation driven by online health misinformation, and highlights the diagnostic and public health implications of such exposure.

Case Presentation

An 80-year-old woman presented with confusion, generalized weakness, anorexia, and polyuria. Laboratory evaluation revealed severe hypercalcemia with a serum calcium level of 15.2 mg/dL and suppressed parathyroid hormone, consistent with PTH-independent hypercalcemia. Her 25-hydroxyvitamin D level was markedly elevated at 265.8 ng/mL, with associated elevation in ionized calcium and calcitriol. The patient was unaware of person, place, or date upon admission. A comprehensive workup was performed to evaluate secondary causes of hypercalcemia. Malignancy, granulomatous disease, and other endocrine etiologies were excluded. Current medications were provided by next of kin detailing over the counter medications and supplements. Further history revealed extensive supplement use, including extremely high intake of vitamin D along with vitamin A, magnesium, and zinc. This regimen was adopted after following recommendations from a social media influencer who was promoting their own brand of high-dose supplementation for general health benefits. The patient required hospitalization and was treated with intravenous fluids, loop diuretics, and corticosteroids. With supportive care and cessation of supplementation, calcium levels gradually normalized and her symptoms resolved.

Discussion

This case illustrates a rare but serious manifestation of vitamin D toxicity resulting from excessive supplementation. Although vitamin D toxicity is physiologically well described, the novel aspect of this case lies in the behavioral driver: medical misinformation propagated through social media. The patient's laboratory profile of suppressed parathyroid hormone with markedly elevated 25-hydroxyvitamin D and hypercalcemia is characteristic of hypervitaminosis D and underscores the importance of including supplement history in the evaluation of hypercalcemia. Despite increasing recognition of misinformation related harm in other areas of medicine, supplement induced toxicity linked to online health advice remains underrecognized and underreported. This case highlights the need for clinicians to routinely ask patients about supplement use and the sources of their health information. It also emphasizes the importance of patient education, evidence-based counseling, and greater awareness of the risks associated with unregulated supplementation practices. At a broader level, this case reflects an emerging public health challenge at the intersection of medicine, communication, and social media. As nonmedical influencers continue to shape health behaviors, clinicians and public health institutions must play an active role in countering misinformation, promoting safe supplementation practices, and advocating for stronger oversight to prevent avoidable harm.

References

Carroll MF, Schade DS. A practical approach to hypercalcemia. Am Fam Physician. 2003;67:1959-1966. [PMID: 12751658]

Asif A, Farooq N. Vitamin D Toxicity. StatPearls. StatPearls Publishing; 2023 (updated 24 May 2023).

Dudenkov DV, Yawn BP, Oberhelman SS, et al. Changing incidence of serum 25-hydroxyvitamin D values above 50 ng/mL: a 10-year population-based study. Mayo Clin Proc. 2015;90:577-586. [PMID: 25939935] doi:10.1016/j.mayocp.2015.02.012

Marcinowska-Suchowierska E, Kupisz-Urbańska M, Łukaszkiewicz J, et al. Vitamin D toxicity-a clinical perspective. Front Endocrinol (Lausanne). 2018;9:550. [PMID: 30294301] doi:10.3389/fendo.2018.00550

Suarez-Lledo V, Alvarez-Galvez J. A bibliometric analysis of the infodemiology of health misinformation research. JMIR Infodemiology. 2023;3:e44418.

Adebesin F, Smuts H, Mawela T, et al. The role of social media in health misinformation and disinformation during the COVID-19 pandemic: bibliometric analysis. JMIR Infodemiology. 2023;3:e48620. [PMID: 37728981] doi:10.2196/48620

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