One of the biggest challenges facing humanity is achieving sustainable food security in the face of population growth, resource scarcity, ecosystem degradation and climate change. Transitioning towards sustainable food systems (SFS) is a must for achieving sustainable development. This review paper highlights the need to adopt a holistic, multidimensional, interdisciplinary and systemic approach for better understanding food systems, which is a prerequisite for fostering transition towards sustainability. A better understanding of food systems means comprehending issues at play from "farm to fork" i.e. production (crop, animal, seafood), processing, trade and distribution, and consumption. For gaining a full awareness also cross-cutting issues such as gender, innovation and technology should be considered. Such a deep knowledge and consequent corrective actions are crucial to address the multiple challenges and dysfunctions of the current global food system such as food insecurity, obesity, food waste, climate change, biodiversity loss, land degradation, water depletion, deforestation, market concentration and food heritage erosion. It is fundamental to foster transition towards sustainable and resilient food systems to achieve sustainable food and nutrition security for present and future generations. All dimensions (environment, economy, society and culture, nutrition and health) of food sustainability should be tackled while considering policy and governance. Different food consumption and production models can help speeding up journey towards sustainability. These include, inter alia, organic agriculture and different alternative food systems allowing to link consumption and production such as urban agriculture, community-supported agriculture and short food chains. While the challenge is titanic, there is a menu of options that can be jointly used to foster shift towards SFS such as sustainable and eco-functional intensification, sustainable diets, food loss and waste reduction. Nevertheless, a holistic and systemic approach is necessary to develop a systems thinking for generating interdisciplinary knowledge needed to support transition towards sustainable food systems.