The Northern Manhattan Longitudinal Population Study examined the association between diet soda consumption and risk of dementia in 947 participants without dementia at baseline[1]. During follow-up, 20% of participants developed dementia, and diet soda was associated with an increased risk of dementia – for each diet soda per day, the risk increased by 39%[1]. Participants who consumed more than one diet soda per day had a 4.15 times higher risk of dementia compared to those who drank less than once per day[1]. This association was particularly observed in non-Hispanic participants[1]. However, after those with obesity or diabetes were excluded from the analysis, the association between diet soda and dementia no longer emerged, suggesting the possibility of reverse causality[1]. A statistically significant association with dementia was not observed for regular soda, although a slight trend emerged[1].