Practising tai chi may help boost immune function and improve blood sugar control in people with type-2 diabetes. Thirty-two people participated in three hour-long tai chi sessions each week, for a period of 12 weeks. Investigators found statistically significant reductions in levels of glycosylated haemoglobin (A1C) in the blood of participants, indicating improved long-term blood glucose control. Increased numbers of regulatory and killer T cells were also found. (Tai chi chuan exercise decreases A1C levels along with increase of regulatory T-cells and decrease of cytotoxic T-cell population in type 2 diabetic patients. Diabetes Care. 2007 Mar;30(3):716-8).