This study evaluates the impact of lifelong dietary restriction on hip osteoarthritis (OA) in 48 Labrador retrievers paired by sex and weight at 6-weeks-old, randomly assigned to ad libitum control feeding (CF) or 25% diet restriction (DR) with the same diet from the age of 8 weeks. A board certified radiologist scored the radiographs of the hip joints taken in the standard view at multiple intervals before 1 year of age and at every birth anniversary thereafter. Evidences of hip joint OA increased throughout the study (15% at 2 years, 67% at 14 years), but dogs from the DR group had lower prevalence and later onset of signs compared to CF dogs (12 years, 6 years).