Many foods contain structural features (such as air spaces, cells, inclusions) that are manifested over a large range of dimensions, including the nanometer range. To make significant advances in delivering foods with excellent quality, the role of microstructure, and its interactions with composition and external conditions must be understood and controlled. This can only be achieved by first developing accurate techniques that detect changes in the internal structure of foods. X-ray CT is a powerful tool for obtaining highly detailed 3D information on internal food structures. Moreover, because of the penetrating capabilities of X-rays, samples can be investigated in a non-destructive manner, thus not majorly altering internal structures by invasive sample preparation. Another advantage of this technology is that it can be used in a range of relevant resolutions to obtain images in the range of millimeter to micron (X-ray micro-CT) and even nanometer (Xray nano-CT) pixel resolution. A selection of moist (sugar foam, apple) and dry foods (cereal products) were scanned using X-ray microand nano-CT. Images, morphometric characteristics and geometric 3D models provided a detailed insight in the various foods in terms of porosity, connectivity and anisotropy of microstructural features. X-ray nano-CT proved to be a valuable yet challenging technique considering sample representability. Nevertheless, X-ray nano-CT enabled the investigation of the 3D microstructure of samples in a near-native state at unprecedented resolutions.