The “cost” has two parts: health impact and the cost of mismanagement. In health terms, inadequate magnesium may worsen neuromuscular complaints, reduce sleep quality, and lower overall well-being. A major hidden cost is misattribution—treating fatigue or cramps as “just magnesium” can delay identifying iron deficiency, vitamin D deficiency, thyroid issues, insulin resistance, or sleep disorders. Another cost is unnecessary high-dose supplementation, which can trigger diarrhea and electrolyte imbalance, leading to lost productivity and wasted spending. A strategic approach is: improve diet first, evaluate persistent symptoms with basic labs (e.g., CBC, ferritin, B12, vitamin D, thyroid), and use supplements only when appropriate and well tolerated. This avoids the cycle of buying products without addressing root causes.