Resistant starch wheat increases PYY and decreases GIP but has no effect on self-reported perceptions of satiety

Authors: HUGHES, RILEY - University Of California, Davis; Horn, William; WEN, ANITA - University Of California, Davis; RUST, BRET - Washington State University; Woodhouse, Leslie; Newman, John; Keim, Nancy

Submitted to: Appetite
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/9/2021
Publication Date: 11/10/2021
Citation: Hughes, R., Horn, W.F., Wen, A., Rust, B., Woodhouse, L.R., Newman, J.W., Keim, N.L. 2021. Resistant starch wheat increases PYY and decreases GIP but has no effect on self-reported perceptions of satiety. Appetite. 168. Article 105802. https://doi.org/10.1016/j.appet.2021.105802.
DOI: https://doi.org/10.1016/j.appet.2021.105802

Interpretive Summary: Although there are numerous health benefits associated with adequate intake of dietary fiber, most Americans do not consume enough fiber on a daily basis to realize these benefits. Wheat is a grain that is consumed widely in the American diet, but the majority of wheat products consumed are baked products that use refined wheat. To address this problem, selective breeding was used to develop a wheat that is high in resistant starch, a type of starch that escapes digestion in the human upper intestinal tract. This wheat is also suitable for baking, and could potentially be exchanged with regular refined wheat in a variety of baked products including bread, rolls, cakes, cookies. ARS scientists tested the resistant starch wheat baked into rolls, and found that circulating hormones associated with increased satiety changed in response to ingestion of the high resistant starch rolls compared to the rolls prepared with regular refined wheat. Thus, incorporation of the resistant starch wheat in baked products has the potential to boost dietary fiber intake, and when ingested in sufficient amounts, these baked products produce hormone signals that promote satiety.

Technical Abstract: Dietary fiber has numerous health benefits, such as increasing satiety, and is regularly included in healthy dietary recommendations. However, different types and sources of fiber have different chemical properties and may therefore differ in their biological effects. This double-blind, randomized, placebo-controlled, crossover study investigated the effects of RS type 2 (RS2) from wheat on objective and subjective indicators of satiety in 30 healthy adults ages 40-65 years of age. Participants ate rolls made using either RS2-enriched wheat flour or a wild-type, control flour for one week before coming in for a test day during which they ate a mixed meal containing the same roll type. Both objective and subjective measures of satiety were measured following the meal to determine whether the RS2-enriched wheat enhanced satiety and suppressed hunger for a longer period than the control wheat. There was an increase in fasting and peak peptide YY3-36 (PYY3-36; pfast = 0.004, ppeak = 0.004) and a decrease in peak and iAUC of glucose-dependent insulinotropic peptide (GIP; ppeak < 0.001, piAUC < 0.001) following ingestion of RS2-enriched wheat. However, there were no significant differences found in subjective measures of hunger or fullness using visual analog scales (VAS) following the test meal.