A diet high in carotenoid-rich vegetables and fruits modifies plasma Interferon alpha-2, Macrophage inflammatory protein-1 beta and Tumor necrosis factor-alpha in healthy individuals

Authors: Jahns, Lisa; Conrad, Zachary; JOHNSON, LUANN - University Of North Dakota; WHIGHAM, LEAH - The Paso Del Norte Institute For Healthy Living; Wu, Dayong; Larson, Kate

Submitted to: Nutrition Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/6/2018
Publication Date: 4/1/2018
Publication URL: https://handle.nal.usda.gov/10113/6472287
Citation: Jahns, L.A., Conrad, Z.S., Johnson, L., Whigham, L.D., Wu, D., Larson, K.J. 2018. A diet high in carotenoid-rich vegetables and fruits modifies plasma Interferon alpha-2, Macrophage inflammatory protein-1 beta and Tumor necrosis factor-alpha in healthy individuals. Nutrition Research. 52:98-104. https://doi.org/10.1016/j.nutres.2018.02.005.
DOI: https://doi.org/10.1016/j.nutres.2018.02.005

Interpretive Summary: Low-grade inflammation is associated with cardiovascular disease, cancer, and diabetes. Regular vegetable and fruit consumption is widely known to be good for health, partly because they often have high amounts of nutrients called carotenoids. But little is known about how carotenoids relate to inflammation. In this study we enrolled 26 healthy individuals from Grand Forks, North Dakota. Participants followed a low-carotenoid diet for six weeks, followed by a high-carotenoid diet for eight weeks. Blood samples were taken at the beginning and end of the study to measure markers of inflammation. We identified an increase in two inflammatory markers and a decrease in one inflammatory marker after participants followed the high-carotenoid diet. These results show that carotenoid consumption influences inflammation in healthy, non-obese individuals.Low-grade inflammation is associated with cardiovascular disease, cancer, and diabetes. Regular vegetable and fruit consumption is widely known to be good for health, partly because they often have high amounts of nutrients called carotenoids. But little is known about how carotenoids relate to inflammation. In this study we enrolled 26 healthy individuals from Grand Forks, North Dakota. Participants followed a low-carotenoid diet for six weeks, followed by a high-carotenoid diet for eight weeks. Blood samples were taken at the beginning and end of the study to measure markers of inflammation. We identified an increase in two inflammatory markers and a decrease in one inflammatory marker after participants followed the high-carotenoid diet. These results show that carotenoid consumption influences inflammation in healthy, non-obese individuals.

Technical Abstract: Vegetable and fruit (VF) intake is generally associated with good health, but the relationship between VF intake and inflammatory markers is unclear due to limited numbers of cytokines measured in most studies. The objective of this study was to determine the association between varying doses of carotenoid-rich VF intake, plasma carotenoids, and a comprehensive array of 26 cytokines and hsCRP.Data were derived from a single-arm controlled feeding study with different levels of carotenoid-rich VF. Individuals followed a low-carotenoid prescription for 6 weeks, then consumed a provided high-VF diet for 8 weeks. Proinflammatory cytokines and plasma carotenoids were measured at baseline and at the end of the 8-week feeding period. Maximum likelihood estimation was used to calculate overall correlations between total plasma carotenoid concentrations and the cytokines. Plasma carotenoids decreased during the low-carotenoid phase and increased during the feeding phase. Of the inflammatory markers measured, we found increased Interferon alpha-2 (P = 0.003), and decreased Macrophage inflammatory protein-1 beta (P = 0.027) and Tumor necrosis factor-alpha (P = 0.012) in plasma after consumption of the carotenoid-rich diet. In conclusion, high-carotenoid VF intake modifies some inflammatory factors in healthy, non-obese individuals. Our findings have provided a new mechanistic interpretation to support the anti-inflammatory benefit of VF consumption