Background <p>Sarcopenia is a complex geriatric syndrome characterized by progressive and generalized loss of skeletal muscle mass, muscle strength, and physical performance. Nutritional factors, including food insecurity, have been reported to be important in the development of sarcopenia. However, evidence on the relationship between sarcopenia and food insecurity is limited, especially with longitudinal data.</p> Aims <p>This study aimed to examine the longitudinal association between sarcopenia, severe sarcopenia, and food insecurity in a nationally representative sample of older adults in Mexico.</p> Methods <p>We used data from the four waves (2009, 2014, 2017, 2021) of the World Health Organization Study on Global Ageing and Adult Health in Mexico. The sample consisted of 1,484 older adults aged 50 years or older. Sarcopenia was defined according to the criteria of the European Working Group on Sarcopenia in Older People. Food insecurity was assessed with two questions related to frequency of eating less and hunger due to lack of food in the last 12 months.</p> Results <p>Moderate (OR = 1.13; 95%CI: 1.09–1.20) and severe food insecurity (OR = 1.19; 95%CI: 1.11–1.27) significantly increased the longitudinal rates of sarcopenia or severe sarcopenia. Meanwhile, the incidence of severe food insecurity increased the cumulative incidence rate of sarcopenia and severe sarcopenia (OR = 1.91; 95%CI: 1.24–2.94).</p> Discussion <p>Since food insecurity is a modifiable structural factor, the implementation of specific programs to alleviate its deleterious consequences is warranted.</p> Conclusions <p>This study shows that moderate and severe food insecurity are associated with an increase in the rates of sarcopenia and severe sarcopenia over time.</p>