Bowman K, et al. - Since weight loss before dementia diagnosis, plus smoking and diseases causing weight loss may confound associations between overweight or obesity at ages <65 years and increased dementia incidence, researchers assessed weight loss before dementia diagnosis, plus short and longer-term body mass index relations to incident dementia in 65–74 year olds within primary care populations in England. Participants included dementia diagnosis free subjects: 257,523 non-smokers without baseline cancer, heart failure or multi-morbidity (group A) plus 161,927 with these confounders (group B), followed ≤14.9 years. Findings revealed that a higher longer-term incidence of dementia was observed in relation to obesity in 65–74-year-olds (free of smoking, cancer, heart failure or multi-morbidity at baseline). The short-term presence of paradoxical associations was also noted, these were seen among those with likely confounders. Biases may be reflected by reports of protective effects of obesity or overweight on dementia risk in older groups, especially weight loss before dementia diagnosis.