The WHO Standardized Acupuncture Points Location [2] will be used to identify the location of these acupoints, Tianshu(ST-25), Daheng(SP-15), Daimai(GB-24), Qihai(CV-6), Zhongwan(CV-12), Zusanli (ST-36), Fenlong(ST-40), and Sanyinjiao(SP-6). After sterilizing the skin, sterile adhesive pads will be pasted on acupoints first, and then needles of size 0.30*75 mm will be inserted into the acupoints to a depth of 50 mm outward and upward slightly. Needles will be lifted, thrust, and twirled evenly 3 times to achieve "de-qi". Paired electrodes of the EA apparatus will be attached transversely to the acupoint respectively with a continuous wave of 50 Hz and a current intensity of 1-5 mA (preferably with the skin around the acupoints shivering mildly without pain) for 30 min. Patients will be treated with electroacupuncture 2 sessions per week over 8 consecutive weeks, 16 sessions for each patient.

The sham electro-acupuncture group (SEA) penetrates acupuncture on non-acupuncture points (1 cm away from the acupuncture point and meridian). The same type of acupuncture needles will be used for SEA with the exact skin sterilization method. All acupuncture points will be needled perpendicularly with a guide tube. Insertion depth will be approximately 50 mm, depending on the location of individual points. Each point will be connected to a sham electro-stimulator (showing a continuous wave at a frequency of 30 Hz but without actual stimulation). All needles will be removed after 30 min of needle retention. Patients will be treated with sham electroacupuncture 2 sessions per week over 8 consecutive weeks, 16 sessions for each patient in total.

The acupuncture needles and related equipment will have already received approval for routine Traditional Chinese Medicine (TCM) clinical practice in Singapore.

delta HOMA-IR = (end-of-treatment fasting insulin (ųU/mL)* end-of-treatment fasting glucose (mmol/L)/22.5) - (baseline fasting insulin (ųU/mL)* baseline fasting glucose (mmol/L)/22.5)

BMI = kg/m2

The waist-hip ratio or waist-to-hip ratio (WHR) is the dimensionless ratio of the circumference of the waist to that of the hips.