The number of food-related products containing nanoparticles increases. To understand the safety of such products, the potential uptake of these nanoparticles following consumption needs to be assessed. In normal safety assessment studies this is investigated using animal models. In this thesis an in vitro model for the prediction of the uptake of nanoparticles in the human body after consumption was developed. The model consists of two parts. The first part is a laboratory incubation model mimicking human digestion in mouth, stomach and intestine. For the second part, human intestinal wall cells are used to assess the uptake of nanoparticles. The two models were combined to take into consideration the potential effect of digestion on nanoparticle uptake in the gut. The main outcome of the work is that the cell-based model can be used to evaluate which nanoparticles are likely taken up by the body at the highest rate. The type of chemical groups on the surface of the nanoparticles greatly influenced their uptake. The developed model can be used to prioritize the nanoparticles for additional investigations. Using this model in the safety assessment of nanoparticles would reduce the number of animals used in safety assessment.