Food security is defined as a situation that exists when all people, at all times, have physical, social and economic access to sufficient, safe and nutritious food that meets their dietary needs and food preferences for an active and healthy life. Four dimensions of food security have been identified in line with different levels. 1) Availability — National. 2) Accessibility — Household. 3) Utilization — Individual. 4) Stability – may be considered as a time dimension that affects all the levels. All four of these dimensions must be intact for full food security. More recent developments emphasize the importance of sustainability, which may be considered as the long-term time (fifth) dimension to food security.
Encyclopedia of Food Security and Sustainability, Volume 2, 2019, pages 1-7,