A recent study in the journal Neurology packs a good news, bad news punch.
First, the good news: moderate to heavy physical activity (such as biking, swimming, and raquetball) protects against the risk of "silent strokes," which are often the first sign of cerebrovascular disease.
In this study, 1,238 middle-aged and older adults (mean age 70 years; 60% women) submitted themselves to MRI tests that could detect evidence of sub-clinical brain infarctions (SBI). Sixteen percent of participants had SBI, but the risk was significantly lower for those who exercised. In fact, older adults who regularly hit the gym were 40 percent less likely to have silent strokes than people who did not exercise.
The bad news: Not everyone in the study benefited equally from exercise. There was no protective effect among study participants who were uninsured or had Medicaid. The researchers write, "It may be that the overall adverse life experience for those who are uninsured or have Medicaid mitigates the protective effect of leisure time physical activity."
In other words, if you're poor, you can't erase the health effects of stress just by breaking a sweat.
Previous research has hinted at this troubling possibility. For example, a 2006 study by medical researchers at Case Western Reserve University reported that healthy behaviors such as not smoking, not drinking in excess, and maintaining a low BMI did not significantly protect the health of low socioeconomic status minorities. The negative effect of low SES overwhelmed the benefits of healthy individual choices. The researchers concluded, "Without addressing the pernicious effects of lower SES, public health initiatives that promote changing individual health behaviors...will result in only modest decreases in racial/ethnic disparities."
It's much easier to tell the uninsured and economically struggling to eat right and exercise than it is to make large-scale political and economic change. But what if these health behaviors only provide meaningful protection to those who have good jobs, private health insurance, and a well-fed bank account?
No easy answers here, but your thoughts welcome in the comments.
Study cited:
1. J. Z. Willey, Y. P. Moon, M. C. Paik, M. Yoshita, C. Decarli, R. L. Sacco, M. S. V. Elkind, and C. B. Wright. Lower prevalence of silent brain infarcts in the physically active: The Northern Manhattan Study. Neurology, 2011; DOI: 10.1212/WNL.0b013e31821f4472.
2. J. J. Sudano and David W. Baker. Explaining US racial/ethnic disparities in health declines and mortality in late middle age: The roles of socioeconomic status, health behaviors, and health insurance. Social Science & Medicine, 2006; Volume 62, Issue 4: 909-922.
