Molybdenum is an essential micronutrient. It plays a complex role in the ecosystem, because the metal is a part of a cofactor for several important enzymes in human, animal and plant metabolism. The physiological requirement for this element is relatively low. Our investigations were aimed at determining the Mo intake of adults in Germany and Mexico by means of duplicate portion technique. Molybdenum was estimated in the food duplicate samples by inductively coupled plasma atomic emission spectrometry. In 1988, 1992 and 1996 the Mo consumption of humans was investigated in 14 test groups of persons with mixed diets. Each test population consisted of seven men and seven women. Furthermore, in 1996 the Mo intake of 10 female and 10 male vegetarians and of two Mexican test groups was also determined. Different factors, such as sex, time of investigation, location and eating habits have an effect on the individual Mo intake. Molybdenum intake of adults with mixed diets has increased significantly from 1988 to 1996. Furthermore, results of our study showed that Mo intake of German adults differs depending on location and the kind of diet. German women with a mixed diet consumed 89 µg d^–1 in 1996 and men 100 µg d^–1. In comparison, female and male vegetarians consumed 179 µg d^–1 and 170 µg d^–1, respectively. There was a significant difference in Mo consumption between German and Mexican test persons. Mexican women consumed on average 162 µg d^–1 and Mexican men 208 µg d^–1. The Mo requirement of adults amounts to about 25 µg d^–1. Our investigations showed that the Mo requirement is met by normal intake. An intake of 150 µg kg^–1 body weight may be toxic for humans. Therefore, people in Germany and Mexico are not endangered by Mo exposure.