Dr. Grossman’s Blog

A recent study shows that higher doses of vigorous exercise are associated with lower risk of age-related macular degeneration (AMD).  AMD is one of the leading causes of blindness in the United States.

Paul Williams, an epidemiologist in Berkeley Lab’s Life Sciences Division studied 41,708 runners (29,532 men and 12,176 women) more than seven and a half years.  He tracked their average daily running distance (kilometers per day), their cardiorespiratory fitness, their body mass index (BMI), cigarette use, and diet.  This data was collected in the National Runners’ Health Study.

The results?

• Men who reported having AMD were significantly more likely to have once smoked cigarettes
• AMD risk was greater in the men and women who consumed more meat and less fruit
• Men and women who reported having AMD ran for exercise significantly less than those who remained unaffected
• The relative risk for AMD decreased 10% per km/d increment in running distance.  Compared with the men and women who averaged less than 2 kilometers/day:

           - those averaging 2 to 4 kilometers/day had 19% lower adjusted risk of AMD

           - those averaging 4 kilometers/day had 42% to 54% lower adjusted risk of AMD

Williams concluded that higher doses of vigorous exercise such as running are associated with lower incident AMD risk independent of weight, cardiorespiratory fitness, and cigarette use.

Learn more about macular degeneration (AMD)

SOURCE:  Prospective Study of Incident Age-Related Macular Degeneration in Relation to Vigorous Physical Activity during a 7-Year Follow-up, Williams, Paul, Investigative Ophthalmology and Visual Science. 2009;50:101-106.