welche mikronährstoffe sollte man testen lassen — what does this mean exactly?

The question 'which micronutrients should one get tested' refers to identifying potential nutrient deficiencies or excesses through blood or other lab tests. Commonly tested micronutrients include vitamin D, vitamin B12, folate, iron, magnesium, zinc, and selenium. However, for generally healthy individuals without specific symptoms or risk factors, broad micronutrient panels are not evidence-based. Many tests have limited clinical utility: blood levels do not always reflect tissue status (e.g., magnesium, zinc), and results can be influenced by season (vitamin D) or recent food intake. Direct-to-consumer (DTC) tests often overinterpret single values and recommend supplements without proven benefit. Targeted testing is more appropriate for risk groups: vegans (B12, iron), older adults (vitamin D, B12), people with malabsorption or chronic diseases, and those on medications like proton pump inhibitors (B12, magnesium). The evidence for routine comprehensive micronutrient screening is weak; it falls more under marketing than established medical practice. Consult a healthcare provider before testing to avoid overdiagnosis and unnecessary supplementation.