Why doesn’t in-vitro success always mean real-world effectiveness?

Cell cultures lack complexity of whole organism systems.

Metabolism alters compounds differently inside living bodies.

Dosages effective in vitro unrealistic in vivo conditions.

Absorption barriers prevent reaching target tissues effectively sometimes.

Interactions with hormones enzymes change expected outcomes dramatically.

Isolated cells ignore immune system influence entirely often.

Bioavailability limits compound reaching effective concentrations in tissues.

Lab environments remove stress variables affecting real responses.

Whole body feedback loops alter biological effects significantly.

Safety profiles differ between cells and organisms greatly.