Zinc is a trace mineral without which the body can't survive. It is involved in more than 100 different enzymatic reactions throughout the body which means if there is a zinc deficiency it will affect many tissues and organs. Zinc plays a major role in the immune system, cell proliferation and growth, and glucose metabolism. Although severe zinc deficiencies are not common in the United States, moderate deficiencies are often overlooked and with time may become serious. Individuals may experience a weakened immune system meaning they have a greater potential for bacterial and/or viral infections to the point of becoming chronically infected. Hearing problems and visual loss have also been reported along with weight loss and anemia. So, anemia and immune system weakness brings about fatigue. Zinc is crucial for the functioning of white blood cells such as macrophages, T-cells and Natural Killer cells.
Activation of the immune system supports decreasing the severity and duration of the common cold and flu. The trace mineral Zinc is also involved in DNA and neurotransmitter synthesis.Clinical studies have been performed on chronic fatigue syndrome patients to determine if they have a zinc deficiency as measured by serum levels. Based on controls, chronic fatigue patients have low levels of zinc and in fact, the lower the amount of zinc that had in their systems correlated with severity of fatigue. Not only were zinc levels low in patients with chronic fatigue but they also had less mitogen-induced CD69+ cells which are T suppressor cells and also fewer CD3+CD8+ suppressor/cytotoxic T-cells. A mitogen is a chemical that induces a cell to make a copy of itself (create a daughter cell). What's going on here is the the immune system is not being activated nor is it being suppressed. This demonstrates that chronic fatigue has a deficiency in the mineral zinc but also problems with the T-cell activation pathways. These patients also have inflammation which is do to down regulation of suppressor T-cells. The lack of the mineral zinc also means these individuals are suffering from oxidative stress due to the loss of zinc and its antioxidant properties. Without proper amounts of zinc infection and inflammation begin to mount.
Zinc has been reported to act as an integral part of generating a host defense on cell surfaces. Zinc has been demonstrated to induce adhesion of monocytes (immature macrophages) to endothelial cells of the vasculature as well as binding of fibrinogen which initiates other white blood cells to migrate to an injured site. In other words, zinc helps white blood cells adhere to blood vessel walls and initiate blood cell infiltration to an injured site.
There are 3 phases to white blood cells getting into an injured site to clean up the mess whether it be due to a physical damage such as a cut or presence of a pathogen. These phases include immigration, diapedesis and emigration. During the initial phase, white blood cells are attracted to the site of injury do to the presence of chemo-attractants and this is known as immigration. Once at the site of injury, these cells need to step through the endothelial cells of the vasculature to enter the site of injury. This is known as diapedeis or stepping through. Local release of histamine from mast cells causes endothelial cells of the vasculature wall to become more permeable and allow blood fluids and small molecules to enter and white blood cells are able to pass between endothelial cells and enter tissues. Once the white blood cells have walked through the vascular endothelial cells (diapedesis) they are said to have emigrated out of the blood vessel where they can do work to clean up the area. Various ions and protein factors add in white blood cell translocation of which zinc is required. Zinc is required for white cell adhesion to endothelial cells before they can get out of the vasculature. Without enough zinc, white blood cells can't adhere to endothelial cells and pass into the damaged area. Symptoms of this are skin lesions that are slow in healing or don't heal at all. Zinc is crucial for repair of tissues due to physical damage or foreign invaders such as viruses and/or bacteria by assisting in the binding of white blood cell to blood vascular endothelial cells. Zinc also activates other molecular pathways that generate a concerted effort amongst all the factors involved in cell adhesion.
The upshot of this is that zinc deficiencies bring about a decrease in B and T-cell mediated immunity that in turn leaves the individual prone to all kinds of infections simply because white blood cells can't get to the injured area. Chronic infections will lead to fatigue and chronic fatigue if left unchecked. This also depletes energy stores further perpetuating that run down or tired feeling.