Effect of a weight-loss program on mental stress-induced cardiovascular responses and recovery

Objective: We assessed the effect of weight loss on blood pressure (BP) and pulse rate during rest, psychological stress, and recovery after stress.Methods: Two groups of men completed two mental stress tests 12 wk apart. The control group continued their usual diet, whereas the weight-loss group underwent a dietary weight-loss program in which they were randomized to a high-fruit/vegetable and low-fat dairy diet or a low-fat diet.Results: Fifty-five men with a baseline BP of 125.9 &plusmn; 6.9/83.6 &plusmn; 7.1 mmHg (mean &plusmn; SD) completed the study (weight-loss group, n = 28; control group, n = 27). The weight-loss group lost weight (mean &plusmn; SEM, &minus;4.3 &plusmn; 0.3 versus +0.4 &plusmn; 0.4 kg, P = 0.001) compared with controls and had a significant decrease in resting systolic BP (SBP; &minus;2.0 &plusmn; 1.1% versus +2.0 &plusmn; 1.1%, P &lt; 0.05). There was a greater decrease in SBP (P &lt; 0.05) and pulse rate (P &lt; 0.05) at all time points during the stress test in the weight loss compared with the control group. At week 12, SBP in 23 (82%) subjects in the weight-loss group and 24 (89%) in the control group returned to resting levels, with recovering levels in the weight-loss group returning to resting levels 6.1 &plusmn; 2.6 min earlier than in the control group (P &lt; 0.05). There was an overall greater decrease in diastolic BP (DBP; P &lt; 0.05) and DBP during recovery up to 27 min after stress (P &lt; 0.05) in the high-fruit/vegetable and low-fat dairy diet group (n = 14) compared with the low-fat diet group (n = 14).Conclusion: A 5% loss of weight decreased BP during rest and returned SBP to resting levels faster, thus decreasing the period of increased BP as a result of mental stress, which is likely to lower the risk of cardiovascular disease in the long term.<br /

Relationship between stress, eating behavior and obesity

Stress is thought to influence human eating behavior and has been examined in animal and human studies. Our understanding of the stress-eating relation is confounded by limitations inherent in the study designs; however, we can make some tentative conclusions that support the notion that stress can influence eating patterns in humans. Stress appears to alter overall food intake in two ways, resulting in under- or overeating, which may be influenced by stressor severity. Chronic life stress seems to be associated with a greater preference for energy- and nutrient-dense foods, namely those that are high in sugar and fat. Evidence from longitudinal studies suggests that chronic life stress may be causally linked to weight gain, with a greater effect seen in men. Stress-induced eating may be one factor contributing to the development of obesity. Future studies that measure biological markers of stress will assist our understanding of the physiologic mechanism underlying the stress-eating relation and how stress might be linked to neurotransmitters and hormones that control appetite.<br /