A big-picture look at the supplement world: how they work, why the advice is so mixed, and what’s behind the marketing. Just a practical, slightly skeptical guide to making sense of it all.

For wonderings, musings, or just a quick hello, feel free to reach out: drhart@hartfamilymedicine.com

Straight Facts:

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• Pickering G, Mazur A, Trousselard M, et al. Magnesium status and stress: the vicious circle revisited. Nutrients. 2020;12(12):E3672. doi:10.3390/nu12123672
• Arancibia-Hernández YL, Hernández-Cruz EY, Pedraza-Chaverri J. Magnesium deficiency and chronic disease. Cellular Physiology and Biochemistry. 2023;57(S1):1–23. doi:10.33594/000000603
• Veatch-Blohm ME, Chicas I, Margolis K, et al. Consistency and contamination in herbal supplements. PLOS ONE. 2021;16(11):e0260463. doi:10.1371/journal.pone.0260463
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• Fedosov SN. Vitamin B12 uptake and balance. Biochimie. 2025. doi:10.1016/j.biochi.2025.12.002
• Dai Q, Zhu X, Manson JE, et al. Magnesium and vitamin D metabolism. American Journal of Clinical Nutrition. 2018;108(6):1249–1258. doi:10.1093/ajcn/nqy274
• Kuang X, Liu C, Guo X, et al. Vitamin K and D effects on bone. Food & Function. 2020;11(4):3280–3297. doi:10.1039/c9fo03063h
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