Mary Beth Genter served as a roving reporter at the SOT 2013 Annual Meeting and submitted the article below.
Diet as a risk factor for susceptibility factor for air pollution susceptibility…who knew?
Two studies from GLACIER (the Great Lakes Air Center for Integrated Environmental Research) presented compelling evidence in laboratory rodents for the role of high fructose-rich diets in promoting various parameters related to metabolic syndrome (a condition that can occur prior to development of type 2 diabetes) and in alterations of heart rate.
Katryn Allen, with GLACIER in conjunction with Michigan State University (MSU), demonstrated that mice fed a diet containing 60% fructose displayed symptoms of insulin resistance, but no changes in body weight or blood insulin. When mice fed the high fructose diet were exposed to ozone for less than one month, there was a marked deterioration of endpoints related to metabolic syndrome. In addition to worsening of HOMA-IR, a measure of metabolic syndrome, the co-exposed mice showed fat accumulation in the liver, and an increase in the capacity to synthesize fats, specifically triglycerides, above and beyond the increases caused by the high fructose diet itself.
In another presentation, MSU professor James Wagner showed the effects of the same model system (high fructose diet + ozone) on the cardiovascular system. Dr. Wagner’s work examined such endpoints as heart rate and heart rate variability. Ozone treatment in high fructose-fed rats dramatically decreased heart rate; a puzzling finding that requires follow up is the observation that co-exposure of the modified diet rats to both ozone and fine particles had a decrease in heart rate variability, compared to those exposed to either air pollutant individually.
Bottom line—while there is some evidence that a diet high in fructose can contribute to endpoints related to metabolic syndrome and type 2 diabetes, the observation that air pollution can exacerbate these endpoints is novel and worthy of attention, particularly for countries dealing with severe air pollution problems and the recent introduction of a Western diet.