Shitake Mushrooms May Boost Immunity

Mushrooms are widely touted for their medicinal qualities, yet very few human intervention studies have been conducted using present-day guidelines. Professor Sue Percival of the University of Florida’s department of Food Science and Human Nutrition, decided to address this issue by conducting a study of 52 healthy adults aged 21 to 41 in order to investigate the effect of mushroom consumption on the immune system. Participants were given a 4-week supply of dry shiitake (Lentinula edodes) mushrooms and were asked to consume either 5 or 10 g of mushrooms daily. Each subject had blood drawn before and after 4-weeks of daily mushroom consumption. Saliva and serum were also collected. Results showed that mushroom consumption led to significantly increased numbers of gamma delta T-cells (γδ-T) and natural killer T-cells (NK-T). Furthermore, both cell types also demonstrated a greater ability to express activation receptors, suggesting that consuming mushrooms improved cell effector function. Mushroom consumption also led to a drop in levels of the inflammatory proteins c-reactive protein (CRP) and macrophage inflammatory protein-1α/chemokine C-C ligand 3 (MIP-1α/CCL3). "If you eat a shiitake mushroom every day, you could see changes in the immune system that are beneficial”, Professor Percival concluded. “We're enhancing the immune system, but we're also reducing the inflammation that the immune system produces."