Aims: The concept of food security and its association with chronic diseases are both well-established. During the years within the scope of the study, there was a significant increase in the body shape index (ABSI) of Indonesian adults. This study tested the hypothesis that the association between food security and chronic diseases is mediated, in part, by ABSI. Methods: Data was obtained from 2156 Indonesian adults using the Indonesia Family Life Survey (IFLS) in 2007 and 2014. Longitudinal study participants were interviewed face-to-face for dietary intake data using the food frequency questionnaire (FFQ). Food security, a concept developed by the World Food Programme (WFP), was calculated based on a food consumption score analysis using the FFQ. A generalized estimating equation (GEE) and a Sobel-Goodman test were used to test the hypothesis in this study. Results: The food consumption score was negatively associated with ABSI. It was also negatively associated with systolic blood pressure (p < 0.001). In a formal mediation analysis, ABSI significantly mediated the pathway between the food consumption score and systolic blood pressure (p < 0.001). Conclusions: The effect of food security on hypertension is mediated through body shape. Strategies to improve the prevention of hypertension among adults may need to take the ABSI and food security, along with nutrition education, into account.