An important mineral that every individual must include in diet is zinc. Zinc boosts immune system, creates DNA, improves sense of smell, and functions as neurotransmitter. Zinc deficiency may result in a number of diseases and disorders such as loss of appetite, diarrhea, stunted growth, hair loss, poor immunity, skin lesions, eye diseases and impotence. Although a good number of zinc supplements are available widely in health food stores and over the counter, natural sources especially animal sources are more powerful. Here is a list of the best foods that are highly rich in zinc and must be included in diet. However, over dosage of zinc may cause side effects such as vomiting, nausea, etc. So, do consult your doctor prior to including these foods in your diet.