The side effects of food additives to the ability of the small intestine cells significantly decreased to absorb nutrients and blocking pathogens. The scientists used a cell culture model of the small intestine to analyze physiological dose at meal containing titanium oxide nanoparticles (30 nanometers) for more than four hours. Acute exposure to food additives not have much effect, but chronic exposure reduced impact on the absorption of the surface of intestinal cells called microvilli. If fewer microvilli, intestinal protection weakened, metabolism slows down and some nutrients such as iron acid, zinc, and fat, and more difficult to absorb nutrients. Enzymes negatively affected, while the signal increased inflammation.