BackgroundOlder informal caregivers are prone to sedentary behavior and obesity. With great caregiving burdens and frequent physical and mental distress, older informal caregivers may have low adherence and poor results in behavioral intervention for weight management. This study examined whether overweight or obese older informal caregivers could benefit from a behavioral weight management program as much as non-caregivers.MethodsThe Mobility and Vitality Lifestyle Program (MOVE UP) was a pre-post, community-based, 13-month lifestyle intervention study to help older adults improve physical function performance and lose weight. We identified a subset of informal caregivers (n = 29) and non-caregivers (n = 65) from the MOVE UP participants retrospectively. Changes in lower extremity function, weight, depressive symptoms, and self-efficacy from baseline were compared between caregivers and non-caregivers using paired t-tests and ANCOVA.ResultsOlder informal caregivers had significantly lower session attendance rates than non-caregivers (67.7% vs 76.8%, P < 0.05), however, both informal caregivers and non-caregivers improved significantly in lower extremity function, weight loss, and self-efficacy in diet (Ps < 0.05). For each outcome, changes from baseline to the 13-month endpoint were the same among informal caregivers and non-caregivers.ConclusionThis study provides evidence that older informal caregivers can benefit from behavioral weight management interventions despite the challenge caregiving poses for effective self-care. Future behavioral intervention studies for older informal caregivers should adopt self-monitoring tools and extend the on-site delivery to home-based settings for higher adherence and greater flexibility.Trial registrationRegistered at clinicaltrials.gov (NCT02657239).