This study builds on prior findings that link increased availability of takeaway food outlets in home, workplace, and commuting environments to greater takeaway consumption and adiposity. Using longitudinal data, we examine associations of takeaway availability at baseline with changes in consumption and adiposity between baseline and follow-up. We analyzed data from the Fenland Study, with baseline data from 2005 to 2015 and follow-up from 2015 to 2020. Takeaway outlet availability within 1 mile of participants' home and workplace addresses, based on 2011 local authority data, was assessed. Outcomes included takeaway food consumption (from a food frequency questionnaire) and body fat percentage (measured via dual-energy x-ray absorptiometry) at follow-up. Among 7581 participants (mean [SD] age, 49.3 [7.4] years) with a mean follow-up of 6.7 years, no positive association was found between takeaway outlet availability at baseline and changes in consumption or body fat percentage. However, among the 12 associations tested, the highest combined home-workplace availability of takeaway outlets, compared with none, was associated with a 0.68 decrease in body fat percentage (95% CI: 0.24-1.12). Although takeaway outletavailability was linked to greater consumption and adiposity at baseline, it did not predict changes over time, underscoring the complexity of dietary behaviors and their relationship with the neighborhood food environment.