When sourcing natural cosmetics, buyers must look beyond marketing claims. Prioritize suppliers that provide INCI (International Nomenclature of Cosmetic Ingredients) lists and verify that products are free from parabens, sulfates, and synthetic fragrances. Check for globally recognized certifications such as COSMOS (Natural/Organic), ECOCERT, or ISO 16128, which defines the calculation of natural and organic indexes. Ensure the supplier can provide a Certificate of Analysis (COA) and Material Safety Data Sheet (MSDS) for every batch to guarantee chemical stability and safety.