Objective To test whether standard information for patients using Crunchie and Aero chocolate bars to explain bone health and risk of fracture is robust. Design Observational study. Setting Domestic kitchen in rural west Wales. Participants 10 Crunchie bars and 10 Aero bars. Main outcome measure Fracture after falls from varying heights. Results Both Crunchie and Aero bars exhibited the same T and Z scores for bone density. Crunchie bars had a lower chocolate mass index than the Aero bars. Crunchie bars are more liable to fracture. Conclusions Using Crunchie and Aero chocolate bars to explain bone structure to patients may be visually attractive but oversimplifies the situation.