Physiological variations in the autonomic responses may be related to the constitutional types defined in Ayurveda

According to Ayurveda, an individual can be classified into any one of the seven constitutional types (Prakriti) depending on the dominance of one, two, or three Doshas. A 'Dosha' is representative of fundamental mechanisms that are responsible for homeostasis, and thus, to health. In the recent years, there have been several efforts to see whether certain physiological, haematological or biochemical parameters have any relationship with the constitutional types or not. The objective of the present study was to see if the results of autonomic function tests vary according to Prakriti of an individual. We conducted this study in clinically healthy volunteers of both the gender belonging to the age group of 17 to 35 years after obtaining their written consent. The Prakriti of these volunteers was assessed on the basis of a validated questionnaire and also by traditional method of interviewing. After confirming that the primary Dosha ascertained by both these methods matched, 106 volunteers were grouped into three on the basis of primary Dosha and were subjected to various autonomic function tests such as cold pressor test, standing-to-lying ratio, Valsalva ratio and pupillary responses such as pupil cycle time and pupil size measurement in light and dark. The results suggest that, the autonomic function tests in the healthy individuals may correlate linearly with the primary Dosha expressed in an individual. In particular, people with Kapha as the most dominant Dosha showed a tendency to have either a higher parasympathetic activity or a lower sympathetic activity with respect to their cardiovascular reactivity in comparison to the individuals with Pitta or Vata as the most dominant Dosha.