Behavioral weight loss interventions (BWLIs) that promote healthy eating as a way to achieve and maintain healthy weights do not work for most people. Most participants encounter significant challenges to behavior change and do not lose weight or maintain meaningful weight loss. For some, there may be negative consequences of participating in a BWLI, including social, psychological and economic costs. The literature is largely silent on these negative unintended consequences, but they are important for both practical and ethical reasons. If efforts to eat healthier have too many negative consequences for individuals and groups, then these efforts are unlikely to be effective, and promoting them may not always be ethical; this would boost the case for moving away from individual-focused efforts as part of healthy eating efforts. Alternatively, if we can make BWLI interventions more effective and more ethical by mitigating these unintended consequences, then it may be too soon to give up on individual-focused efforts. We make a case for systematic assessment and reporting of the unintended consequences of BWLI. This could contribute to more effective and ethical BWLI and inform obesity interventions and policies more broadly.