Day 89- Relax Ladies!

Guest Blog Author Amanda Buhl, MPH

Amanda received her Masters in Public Health Nutrition from the University of Washington School of Public Health in March, 2011.

Chronic psychological stress and the daily demands of modern life have profound consequences for human health and wellbeing. In particular, chronic stress appears to be consistently associated with a preference for energy-dense foods, namely those high in fat and sugar (1-9). Evidence from longitudinal studies also suggests that chronic stress may be causally linked to weight gain and greater abdominal and visceral fat (1-3, 10).

Stress contributes to weight gain through both modifications in food choice (eating more calories and “comfort foods” high in fat and sugar) and other, metabolic changes. In conditions of chronic stress, the hormonal balance is shifted toward low levels of fat-preventing anabolic hormones (androgens and IGF-1) and increased levels of cortisol (the main stress hormone) and insulin. Cortisol promotes the accumulation of fat around your middle because abdominal and visceral fat (the particularly unhealthy fat found around your organs) have a greater density of cortisol receptors (2, 3, 11). Also, the combination of insulin and cortisol inhibits fat breakdown and promotes fat storage through activation of lipoprotein lipase, the fat storing enzyme that converts triglycerides into stored fat.

To test the hypothesis that chronic stress is associated with greater levels of overweight and obesity, I examined survey data from 2,000 Seattle households as part of the Seattle Obesity Study (SOS). The SOS is a multidisciplinary study of food access, diet quality, and health among adults in King County led by the University of Washington Center for Obesity Research.

What the data in my study demonstrated was that, particularly among women, there was a STRONG, statically significant, positive association between self-rated stress levels and overweight/obesity (as measured by body mass index), even after controlling for numerous demographic (age, race/ethnicity), socioeconomic (income, education), and lifestyle (physical activity, smoking, fruit and vegetable consumption) variables that we know to be associated with either stress or overweight (or both). So these variables did not affect (or confound) the relationship that was seen here. Among men, a statistically significant association was not seen after controlling for the potentially confounding variables listed above, suggesting that these variables might explain the incidence of overweight in the men in this study more than stress. Though this type of study does not allow us to assume that there is a causal relationship between stress and weight gain, these findings definitely warrant further investigation.

PUNCHLINE: There may be something unique happening in women’s bodies that make us more vulnerable to the effects of stress, particularly the fat-accumulating effects of stress. Recent research has proposed that women may be more sensitive to low levels of corticotrophin releasing factor – the neuropeptide released in the brain in response to stress – signifying a difference between men and women in the physiological response to stress (12). Additionally, research has shown that following a spousal argument, women experience a prolonged stress response (elevated cortisol levels) as compared to men (13). This may suggest a greater vulnerability to social or relationship stress among women.

So ladies (and gents), check your stress levels. Dedicate time each day for activities and exercise outlets you enjoy. Also, develop social support networks where you feel comfortable and can seek guidance and help when you need it. Your body will thank you!

Keep calm and carry on,

Amanda

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