To examine associations between perceived weight discrimination and changes in weight, waist circumference, and weight status.Data were from 2944 men and women aged ≥50 years participating in the English Longitudinal Study of Ageing. Experiences of weight discrimination were reported in 2010-2011 and weight and waist circumference were objectively measured in 2008-2009 and 2012-2013. ANCOVAs were used to test associations between perceived weight discrimination and changes in weight and waist circumference. Logistic regression was used to test associations with changes in weight status. All analyses adjusted for baseline BMI, age, sex, and wealth.Perceived weight discrimination was associated with relative increases in weight (+1.66 kg, P < 0.001) and waist circumference (+1.12 cm, P = 0.046). There was also a significant association with odds of becoming obese over the follow-up period (OR = 6.67, 95% CI 1.85-24.04) but odds of remaining obese did not differ according to experiences of weight discrimination (OR = 1.09, 95% CI 0.46-2.59).Our results indicate that rather than encouraging people to lose weight, weight discrimination promotes weight gain and the onset of obesity. Implementing effective interventions to combat weight stigma and discrimination at the population level could reduce the burden of obesity.