Scope Chronic, low-grade inflammation is a hallmark of many noncommunicable diseases, including obesity. Diets enriched with tomatoes and soy have been associated with better health outcomes in inflammation-related illnesses, with lycopene and isoflavones considered key bioactive components, respectively. On the basis that whole food combinations may exert greater effects than isolated phytochemicals, we examine the anti-inflammatory and metabolic effects of tomato-soy juice compared to a low carotenoid tomato juice control in obesity. Methods and results In a randomized, crossover trial, 12 healthy adults with obesity were provided either tomato-soy juice (54 mg lycopene/d, 189.9 mg isoflavones/d) or a low carotenoid tomato juice (no isoflavones) daily for 4 weeks, then crossed over to the other treatment following a washout period. Plasma carotenoids, cytokines, and the urine metabolome were measured pre- and post-interventions. Plasma lycopene significantly increased by 2.48-fold after tomato-soy intake. IL-5, IL-12p70, and GM-CSF significantly decreased (P < 0.05), and TNF-α trended downward (P = 0.052) following tomato-soy. Soy isoflavones and their metabolites primarily distinguished post-tomato-soy urine profiles. Both interventions induced some shared metabolomic changes in the urine, indicating tomato-driven effects independent of lycopene. Conclusion Tomato-soy intake reduced some pro-inflammatory cytokines and altered the urine metabolomic profile in adults with obesity, supporting future studies using this functional food product for other inflammation-related conditions.

The authors have declared no competing interest.

NCT03783013

This work was supported by grants from the United States Department of Agriculture (NIFA AFRI 2018-67017-27519, National Needs Fellowship 2020-38420-30723, and Hatch OHO01470, OHO01563, and OHO01538) and the National Institutes of Health (R01DK138871). Research was additionally supported by Lisa and Dan Wampler Endowed Fellowship for Foods and Health Research, and the Foods for Health Initiative at the Ohio State University.

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IRB of Chesapeake (now Advarra) gave ethical approval for this work.

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Raw MS1 data are available in Metabolomics Workbench (ST004178) and data-dependent MS/MS data have been reposited with GNPS MassIVE (MSV000099128). Code for metabolomics, carotenoids, and cytokines analyses can be found at https://github.com/CooperstoneLab/TomatoSoy-Obesity-Metabolomics.

https://github.com/CooperstoneLab/TomatoSoy-Obesity-Metabolomics.