Impact of cattle feeding-style on beef and human postprandial inflammation

Abstract

Purpose: Various cattle-feeding styles have arisen in recent years, impacting the sustainability and environmental practices of many producers. While these changes are known to have an impact on the environment, little is known about the direct impact cattle raised using different feeding styles has on human health. Acute response focused studies, like this, are a glimpse into the expected impact of a certain food on the diet over time. The purpose of this study is to investigate the impact of cattle-feeding style on postprandial inflammation. Methods: A randomized, double blind, crossover study design was used to compare grass-fed (GRA) and conventional (CON) beef. Subjects (n=10) were comprised of men and women with a healthy body mass index (BMI) and no preexisting metabolic conditions. Blood samples were collected fasted and postprandially for four hours. Blood samples were analyzed for inflammation markers (TNF-alpha, IL-23, IL-17, IL-10, IL-1beta, IL-6, IFN-gamma and GM-CSF) at hourly timepoints. To observe postprandial changes with and without consideration for cattle feeding style, the net area under the curve (AUC) was calculated. Maxchange and CMAXtime were calculated by finding the maximum value of each cytokine between hours one and hour postprandially and subtracting that from the fasting value. CMAXtime represents the time at which the maximum value of each cytokine was reached in hours. Maxchange and AUC responses were compared to zero using a one-sample t-test to determine if response was greater than fasting. Results: In response to beef, maxchange of all measured markers and IFNgamma AUC were significantly greater than zero (p< 0.05). No differences were shown between GRA and CON in inflammation AUC (p> 0.05). Conclusion: This demonstrates that beef consumption does increase postprandial inflammation, but cattle-feeding style does not significantly impact this response.