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ARS Home » Plains Area » Mandan, North Dakota » Northern Great Plains Research Laboratory » Research » Research Project #445549

Research Project: Comparing the Healthfulness of Grass-fed and Grain-fed Beef

Location: Northern Great Plains Research Laboratory

Project Number: 3064-21600-001-017-A
Project Type: Cooperative Agreement

Start Date: Nov 1, 2023
End Date: Aug 31, 2024

Objective:
Determine if consumption of grass-fed beef elicits more healthful inflammatory and metabolite profiles in adults in comparison to grain-fed beef.

Approach:
Chemical composition of beef sources – vitamin and mineral derivatives, fatty acids, organic acids, phenolics, xenobiotics, and bioactives – will be determined via untargeted metabolomics and overlaid with the serum and gut microbiome metabolome of participants to directly establish the impact of phytochemical richness of the meat on the human metabolome. Also, a human intervention study will be conducted: subjects: twenty middle-aged adults (35-65 years) of all races and ethnicities will participate; inclusion criteria: body mass index =25 and <35.0 kg/m2; weight stable (±4.5 kg); and consistent physical activity levels; exclusion criteria: use of tobacco products; medications that can affect inflammation; and/or evidence of disease (e.g., diabetes, impaired kidney function, cancer, etc.). We will use a randomized, double-blind, cross-over design. Subjects will consume each source of beef (grass- or grain-fed) as part of a controlled diet for 21-days with a 7-day washout period in between different meats, where subjects are allowed to consume foods in a self-selected unrestricted eating pattern. The 21-day interventional diets will be identical in all other foods (fruits, vegetables, grains etc.) and only differ in the source of beef consumed during this time. Plasma and stool samples will be taken in the morning after an overnight fast prior to- and after both dietary interventions. Concentrations of 20 plasma inflammatory biomarkers will be measured by multiplex electro-chemiluminescence. 16s rRNA gene sequencing of stool samples will be used for taxonomic profiling of the gut microbiome. Serum and gut metabolites will be determined via untargeted metabolomics. Change scores (post – baseline) will be created for inflammatory markers and metabolites. Partial Least Square Discriminant Analysis (PLS-DA) of metabolomics data will be used to provide unbiased, in-depth insight into the metabolic activity of participants after the ingestion of the specific beef sources.