Observation of sympathomimetic effect of ear acupuncture stimulation for body weight reduction

Ear acupuncture stimulation has been used for body weight reduction as early as the 1970s. Several hypotheses have been proposed in literature regarding its mechanism of action, among which are the effects of the stimulation of the hypothalamic satiety center on decreased neuropeptide Y production. Here, we present another possible mechanism to account for the temporary and short-term effects of ear acupuncture stimulation in the treatment of obesity, the sympathetic effects of the autonomic nervous system. 14 female volunteers underwent a randomized clinical trial of the ear acupuncture stimulation. A prospective, sham-point control, crossover study was performed with two sequential four-week stimulation periods separated by a two-week washout interval. The clinical features of and effects on the autonomic nervous system were recorded and analyzed. Decreased body weight was observed in both the experimental and the control groups in the first 4 weeks of stimulation. Sympathomimetic effects were also noted in both groups. Whereas the sympathomimetic effects and body weight reduction were sustained in the experimental group in the second 4 weeks of stimulation, such effects were not observed in the control group. Some sympathomimetic effects were noted in both the experimental and the control groups initially. This effect remained apparent in the experimental group in sequential stimulation but was lost in the control group. Consequently, we believe that sympathomimetic effects may account for the reduction in body weight by temporarily increasing basal metabolic rate and decreasing appetite, but the body may regain weight after the termination of such effects. Accordingly, the combination of an optimal exercise and diet program with repeated acupoint therapy may be necessary to maintain a healthy body weight.