Zinc Complex (Shaklee Products) . . . Nature's Metabolic Workhorse. It’s present in all cells in the body. As part of enzyme reactions, zinc is involved in such diverse biochemical activities as protein digestion, amino acid metabolism, energy production, bone metabolism, vitamin A utilization, and insulin production. Zinc is necessary for growth and development, and to maintain normal immune function. It is also important for the synthesis of protein and the genetic material DNA.  Zinc Can Improve Memory and Attention Span. Adding supplemental zinc to the diets of middle– schoolers led to improvements in both memory and attention span, according to preliminary research conducted at the U.S. Department of Agriculture’s Grand Forks Human Nutrition Research Center in North Dakota. In the study, kids given 20 mg of zinc five days a week for 10 to 12 weeks performed better on memory tasks and had longer attention spans than those who did not receive zinc supplements. Size: 120 Tablets