Its action is described as being complementary to that of the sympathetic nervous system, which is responsible for stimulating activities associated with the fight-or-flight response. Nerve fibres of the parasympathetic nervous system arise from the central nervous system. Specific nerves include several cranial nerves, specifically the oculomotor nerve, facial nerve, glossopharyngeal nerve, and vagus nerve. Three spinal nerves in the sacrum (S2-4) also act as parasympathetic nerves.
A healthy BMI is considered to be between 18.5 and 24.9. Based on these BMI tables, the National Heart, Lung and Blood Institute suggests that a healthy weight range for women who are 5 feet 4 inches tall is 110 to 140 pounds.
A BMI under 19 is underweight, 19 through 24 is the healthy weight range, 25 through 29 is in the overweight range, and a BMI of 30 and above is the obese range. For those who are overweight or obese, modest weight loss (e.g., 10 pounds) has health benefits, and the prevention of further weight gain is very important. Eating fewer calories while increasing physical activity are the keys to controlling body weight.