Collagen effects depend on tissue turnover, so thinking in weeks-to-months is more realistic than days. Skin outcomes such as elasticity and hydration are often reported after 8–12 weeks in clinical studies. For joint-related outcomes, consistent use for 2–3 months or longer is commonly evaluated. A practical approach is a 12-week trial: record baseline metrics (photos, skin feel, joint discomfort score, nail brittleness), then reassess objectively. If there is no benefit, revisit collagen type, dose, formulation, and lifestyle foundation. If benefits are clear, you can consider cyclic use or a maintenance plan at a sustainable dose. For longer use, prioritize product quality and overall protein balance.