to add to that, grabbed this from msrc.co.uk
Zinc is also important in the production of prostaglandins (PGs). PGs are vital to numerous body functions including, for example: the function of the immune system; the expression and control of inflammation; skin and wound healing; function of the heart and cardiovascular system; absorption of various minerals; body temperature control and the important functions of fertility, conception, and delivery of the infant.
The way in which zinc influences PG production is by potentiating (or supporting the function of) the enzymes which permit the conversion of the polyunsaturated fatty acids into PGs. Zinc thus has a very direct action in stimulating the normal production of PGs thereby maintaining or restoring normal health and fitness.
Zinc deficiency can result in many symptoms, including: loss of appetite, growth retardation, diarrhoea, tremor, hair loss, dandruff, a dry skin rash, white lines on fingernails, increased allergic sensitivity, disturbance of menstrual periods, pre-menstrual syndrome, delay of wound healing, loss of taste or smell sensation, dyslexia, poor night vision, photophobia (sensitivity to light), depression, sleep disturbance, hyperactivity, reduced fertility, loss of sex drive, pre-eclampsia (toxaemia) of pregnancy and post-natal depression.