In 1933, zinc was reported for the first time to be essential for the growth of rats (Todd et al. 1933). Thirty years later, the first studies in human subjects from the Middle East showed that this was also true for humans (Prasad et al. 1961, 1963a, 1963b). However, with the exception of mental lethargy, little was mentioned in these reports on possible neurological effects of zinc deficiency in these patients. Only in later studies was it found that zinc deficiency might compromise emotional and cognitive functioning (Black 1998; Bhatnagar and Taeja 2001). To date, many studies have been performed investigating the influence of zinc deficiency and zinc supplementation on human well-being and mental performance. However, particularly in mechanistic and behavioral studies, the majority of data available to date regarding the effects of zinc deficiency on brain development and function later in life comes from findings in animal models (Hagmeyer et al. 2014).