Effect of Non-Vegetarian Diet on Cardiovascular Reactivity to Mental Stress in Young Adults

We compared the role of vegetarian and non-vegetarian diet on vascular reactivity in response to mental stress. Vegetarian under-graduate medical students (n = 100) were compared with non-vegetarian students (n = 100) both at rest and after examination stress. The measured parameters included systolic blood pressure (SBP), diastolic blood pressure (DBP), pulse pressure (PP), mean blood pressure (MBP) and heart rate (HR). Both groups showed significant vascular reactivity to mental stress but the non-vegetarians had higher BP and HR values both at rest and after exposure to stress. Under resting conditions, the SBP, DBP, PP, MBP (mmHg), HR (bpm) in the vegetarians were 127.7 ± 6.4, 77.8 ± 4.4, 49.9 ± 5.9, 94.5 ± 4.3, 77.1 ± 2.1 and in the non-vegetarian group were 133.7 ± 7.7, 86.0 ± 5, 47.7 ± 6.8, 101.9 ± 5.1, 82.3 ± 2.7, respectively. All the values except PP in the non-vegetarian group were significantly higher when compared with the vegetarian group (p < 0.05). After exposure to stress, the SBP, DBP, PP, MBP (mmHg), HR in the vegetarian group were 132.2 ± 6.5, 80.3 ± 4.6, 51.8 ± 6.8, 97.6 ± 4.2, 82.3 ± 2.7 and in the non-vegetarian group were 141.9 ± 7.9, 91.8 ± 6.7, 50.0 ± 7.5, 108.5 ± 6.2, 86.4 ± 3.0, respectively. All the values except PP in the non-vegetarian group were significantly higher when compared with the vegetarians (p < 0.05). The post-stress values were significantly greater than those taken at rest (p<0.05). This study showed better coping to mental stress in vegetarians and suggests a greater risk to develop future hypertension in non-vegetarians according to the reactivity hypothesis. Prospective follow-up studies are needed to test this hypothesis.