Mineral deficiency is usually identified through (1) symptoms and risk factors and (2) lab confirmation. Symptoms may include fatigue, cramps, frequent infections, brittle hair/nails, dizziness, and palpitations. Risk factors are often more predictive: heavy menstrual bleeding, pregnancy, restrictive diets, malabsorption, chronic diarrhea, bariatric surgery, heavy sweating, older age, and certain medications. Targeted tests follow—ferritin/CBC for iron, serum magnesium for magnesium, serum zinc for zinc—interpreted within clinical context. A single number rarely gives a definitive answer; inflammation can alter markers, and acute illness can affect results. Clinician interpretation and, when needed, repeat testing improve accuracy.\n\nSource note: NIH ODS mineral fact sheets (risk-based approach and measurement considerations).