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bioRxiv · 10.1101/2023.08.26.554975

The consumption of iceberg lettuce may reduce the adhesion of dietary fat to the mucus surface of the stomach barrier lining decreasing the risk of triggering acute gastroesophageal reflux

Hurr, T.
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Abstract

Iceberg lettuce (IL) leaves contain surface epicuticular waxes that can adsorb significant quantities of dietary fat per unit weight. Fats such as olive oil, butter, lamb fat and lard readily adsorb onto IL with soft solid fats contained in lamb fat and lard, showing strong adhesion and more resistance to removal on rinsing in a water stream. Dishwashing detergents containing surfactants prevent the adsorption of both liquid and solid fats to the lettuce leaf surface, unless at very low concentrations, highlighting their significant influence on surface properties. Based on the adhesion of fats to the IL leaf surface, it is proposed the consumption of IL could reduce acute gastroesophageal reflux (GER) and the development of gastroesophageal reflux disease (GERD). In diets containing fat, the adhesion to IL reduces the amount of fat available to adhere to the mucus surface of the stomach barrier lining, protecting the lining and reducing access by trigger foods to underlying surfaces that could potentially initiate GER. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=44 SRC="FIGDIR/small/554975v1_ufig1.gif" ALT="Figure 1"> View larger version (14K): org.highwire.dtl.DTLVardef@159cb99org.highwire.dtl.DTLVardef@45cf6eorg.highwire.dtl.DTLVardef@1355263org.highwire.dtl.DTLVardef@1b3fad2_HPS_FORMAT_FIGEXP M_FIG C_FIG Iceberg lettuce leaves have approximately twice the surface area of the stomach for a 50g serve and 500cm3 meal volume and due to the waxy surface, can adsorb significant amounts of dietary fat. Lettuce may also adsorb on the mucus layer of the stomach barrier lining but is not regarded as a trigger food. Lettuce with its large surface area to adsorb fat, can keep fat suspended in solution, protecting the lining from fat adsorption and reducing the probability that fatty trigger foods can access underlying surfaces and cause acute gastroesophageal reflux.

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Hurr, T.. 2023-08-28. The consumption of iceberg lettuce may reduce the adhesion of dietary fat to the mucus surface of the stomach barrier lining decreasing the risk of triggering acute gastroesophageal reflux. https://doi.org/10.1101/2023.08.26.554975

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