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bioRxiv · 10.1101/249763

TAS2R38 predisposition to bitter taste associated with differential changes in vegetable intake in response to a community-based dietary intervention

Abstract

BackgroundAlthough vegetable consumption is associated with decreased risk for a variety of chronic diseases, few Americans meet the CDC recommendations for vegetable intake. The TAS2R38 gene encodes a taste receptor that confers bitter taste sensing from chemicals found in some vegetables. Common polymorphisms in TAS2R38, including rs713598, rs1726866, and rs10246939, lead to coding substitutions that alter receptor function and result in the loss of bitter taste perception.\n\nObjectiveOur study examines whether bitter taste perception TAS2R38 diplotypes were associated with vegetable consumption in participants enrolled in either an enhanced or a minimal nutrition counseling intervention within a community-based dietary intervention.\n\nMethodsDNA was isolated from the peripheral blood cells of study participants (N = 497) and analyzed for polymorphisms using genotyping arrays. The Block Fruit and Vegetable screener was used to determine frequency of vegetable consumption. Mixed effects models were used to test differences in frequency of vegetable consumption between intervention and genotype groups over time.\n\nResultsThere was no association between baseline vegetable consumption frequency and the bitter taste diplotype (p = 0.937), however after six months of the intervention, we observed an interaction between bitter taste diplotypes and time (p = 0.046). Participants in the enhanced intervention increased their vegetable consumption frequency (p = 0.020) and within this intervention group, the non-bitter and intermediate-bitter tasting participants had the largest increase in vegetable consumption. In contrast, in the minimal intervention group, the bitter tasting participants reported a decrease in vegetable consumption.\n\nConclusionsNon- and intermediate-bitter taste blind participants increased vegetable consumption in either intervention group more than those who perceive bitterness. Future applications of precision medicine could consider genetic variation in bitter taste perception genes when designing dietary interventions.\n\nAuthor summaryMost Americans under consume vegetables, despite clear associations between vegetable consumption and health benefits. Vegetables, such as broccoli, kale, and Brussels sprouts, contain bitter-tasting compounds, leading to taste aversion. Common polymorphisms on the TAS2R38 taste receptor gene (rs713598, rs1726866, and rs10246939) influence the perception of bitter taste. We tested whether genetic predisposition to bitter taste influenced vegetable intake in a dietary intervention and found that TAS2R38 diplotypes were related to vegetable consumption. Combining precision medicine approaches that identify taste profiles and personalizing dietary advice could help engage intervention participants and improve the impact of dietary interventions.

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Calancie, L., Keyserling, T. C., Smith-Taillie, L., Robasky, K., Patterson, C., Ammerman, A. S., Schisler, J. C.. 2018-01-18. TAS2R38 predisposition to bitter taste associated with differential changes in vegetable intake in response to a community-based dietary intervention. https://doi.org/10.1101/249763

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