(P19-014-25) Effects of Organic Versus Conventional Beef on the Gut Microbiome, Inflammatory Markers and Plasma Lipids in Overweight and Obese Individuals

Objectives: Organic beef from pasture raised cows contains plant-derived phytochemicals, including phenolics and flavonoids, and about 4 times more omega-3 fatty acids than beef from conventionally raised, grain-fed cows. Due to the health-promoting effects these compounds, perhaps through the gut microbes, we compared the effects of organic to conventional beef on the gut microbiome and associated biological changes.

Methods: We conducted a double-blind, two-arm dietary cross-over study, with a 4-week washout period between study arms. Participants consumed four weekly servings of about 100 g of organic beef for 4 or 8 weeks, and after the washout period, another 4 or 8 weeks of conventional beef, or vice versa. Participants selected beef products to consume from 4 ready-made meals or beef patties. At baseline, we performed three 24-hour dietary recalls, collected stool and blood samples, and measured body weight. A1C levels were also assessed to screen for diabetes, an exclusion criterion. During arm 1, washout period, and arm 2, dietary intakes were assessed again, and biological samples and body weight were collected by the study team.

Results: Forty-nine healthy men and women with a BMI ≥ 25 kg/m² started beef intake between January and October 2024. All participants were regular meat consumers, but only consumed beef provided by the team during the intervention. Ten participants dropped out (20%), and 39 completed the study. Preliminary data analysis suggests that beef intake did not affect body weight or energy intake, compared with the baseline. From the stool samples, we are currently performing gut microbiome and metabolite analysis. Blood samples will be analyzed for lipid levels, inflammatory cytokines, short chain fatty acids (SCFAs), SCFA receptors, and GLP-1 levels.

Conclusions: Our study will generate data to determine if organic beef beneficially affects the gut microbiome and consequently might reduce inflammatory markers and increase circulating levels of HDL cholesterol and GLP-1.

Funding Sources: The study was funded by Applegate Farms, LLC. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.