The impact of the 2021 Thrifty Food Plan benefit re-evaluation on SNAP participants’ short-term food security and health outcomes

INTRODUCTION: The Supplemental Nutrition Assistance Program (SNAP) is the largest federal nutrition assistance program in the United States, and played a critical role in mitigating food insecurity during the COVID-19 pandemic. In 2021, the updated Thrifty Food Plan (TFP), which provides the basis of SNAP benefit allotments, led to a 21% monthly benefit increase for SNAP participants. The objective of this study was to examine the effects of the TFP re-evaluation on food insecurity, diet quality, and mental health using a natural experiment design. METHODS: A longitudinal, web-based study was conducted among 1,004 United States adults with incomes at or below $65,000 in September 2021 (prior to the policy change) and February 2022 (after the policy change). Outcomes of interest included household food security, diet quality, perceived stress, and anxiety/depression, assessed using validated instruments. We used difference-in-differences regression modeling to assess the effects of the policy change on participants’ outcomes, adjusting for sociodemographic covariates. Qualitative responses to open-ended questions about the policy change were analyzed using thematic analysis. RESULTS: Prior to the policy change, SNAP participants had significantly worse food insecurity, lower diet quality scores, and higher perceived stress and anxiety/depression when compared to non-participants (all Ps < 0.05). After adjustment for differences in sociodemographic characteristics, there were no significant effects of the TFP re-evaluation on food insecurity, diet quality, and mental health outcomes among SNAP participants relative to non-participants (all Ps > 0.05). Qualitative responses suggested that rising food prices and growing inflation potentially negated the benefits of the policy change; however, most SNAP participants described the added benefits as helpful in purchasing additional food supplies and offsetting other household costs during this period. DISCUSSION: The TFP benefit increase may have helped to prevent inflation-related disparities in food insecurity and health outcomes from widening among SNAP participants and non-participants. Further research is needed to determine the long-term impacts of this policy change.