The prebiotic activity of a commercially available oat product and a novel oat ingredient, at similar β-glucan loads, was tested using a validated in vitro gut model (M-SHIME^®). The novel oat ingredient was tested further at lower β-glucan loads in vitro, while the commercially available oat product was assessed in a randomised, single-blind, placebo-controlled, and cross-over human study. Both approaches focused on healthy individuals with mild hypercholesterolemia. In vitro analysis revealed that both oat products strongly stimulated Lactobacillaceae and Bifidobacteriaceae in the intestinal lumen and the simulated mucus layer, and corresponded with enhanced levels of acetate and lactate with cross-feeding interactions leading to an associated increase in propionate and butyrate production. The in vitro prebiotic activity of the novel oat ingredient remained at lower β-glucan levels, indicating the prebiotic potential of the novel oat product. Finally, the stimulation of Lactobacillus spp. was confirmed during the in vivo trial, where lactobacilli abundance significantly increased in the overall population at the end of the intervention period with the commercially available oat product relative to the control product, indicating the power of in vitro gut models in predicting in vivo response of the microbial community to dietary modulation.

The topic of sweet taste and the relationship to health is one that has been of interest to researchers for many years. Recently, reduced consumption of sweet-tasting foods and beverages, regardless of how they are sweetened (ie, caloric or low/no-calorie sweeteners), has been recommended by some health authorities to encourage reduced sugar consumption. The hypothesized rationale is that human attraction to sweetness could increase the risk of developing less healthy eating patterns. This article summarizes the work presented by Professors Appleton and de Graaf on the topics of sweet taste perceptions and preferences, food intakes and obesity, during an American Society for Nutrition webinar on July 28, 2020, and finds little evidence to support this hypothesis.

Despite recommendations to reduce sweet-tasting foods and beverage consumption, there is limited understanding of our ability to adapt to a less sweet diet and the optimal method for doing so. Thus, we conducted two parallel, double-blind, randomized controlled trials in the USA and Mexico to investigate whether different methods of reducing sweetness could change sweetness preferences. Over 6 months, habitual consumers of full-sugar sweetened (FSS-CSD) or low-calorie sweetened carbonated soft drinks (LCS-CSD) consumed a full sweetness CSD (Control), CSD with gradually decreasing sweetness levels (StepR), and a reduced sweetness test CSD (DirR). The StepR and DirR methods were similarly effective in helping the USA FSS-CSD cohort maintain their preference for reduced-sweetness CSD, without affecting sweetness intensity perception. However, neither method significantly impacted the sweetness intensity perception or preference of the USA LCS-CSD cohort, and the FSS-CSD and LCS-CSD cohorts in Mexico. Nevertheless, participants from both sweetness reduction groups in all cohorts were more willing to purchase reduced sweetness CSD compared to Control, underscoring the potential for consumer acceptance of less sweet beverages regardless of adaptation strategies. This trial was registered at www.clinicaltrials.gov as NCT04609657 and NCT05010408.

An agreed-upon measure of total dietary sweetness is lacking hindering assessments of population-level patterns and trends in dietary sweetness. This cross-sectional study used 24-h dietary recall data for 74,461 participants aged ≥ 2 y from nine cycles (2001–2018) of the National Health and Nutrition Examination Survey (NHANES) to evaluate trends in the sweetness of the diet in the United States (US). LCS-containing items were matched to a sugar-sweetened counterpart (e.g., diet cola–regular cola or sucralose sugar). The matched pair was used to estimate the sugar equivalents from LCS-sweetened foods or beverages to estimate dietary level sweetness, which was described as grams of approximate sugar equivalent (ASE) per day. Trends in ASE were estimated overall and by subgroup, and trends were further disaggregated by food or beverage category. Overall, LCS sources contributed about 10.5% of ASE. Total ASE declined from 152 g/d to 117 g/d from 2001–2002 to 2017–2018 (p-trend < 0.001), with comparable declines in children and adults. Declines in total ASE were predominantly driven by beverages (−36.7% from 2001–2002 to 2017–2018) and tabletop sweeteners (−23.8%), but not food (−1.5%). Observed trends were robust to sensitivity analyses incorporating random, systematic, and sensory trial informed estimates of sweetness and also an analysis excluding possible under-reporters of dietary energy. This practical approach and underlying data may help researchers to apply the technique to other dietary studies to further these questions.

Corrigendum: Estimated Sweetness in US Diet Among Children and Adults Declined From 2001 to 2018: A Serial Cross-Sectional Surveillance Study Using NHANES 2001–2018

Reducing sugars consumption is an important public health priority. Because reducing one’s sugar intake is challenging, some organizations have suggested reducing the consumption of all sweet-tasting foods and beverages, regardless of the source of the sweet taste (i.e., caloric or low/no calorie sweeteners (LCSs)), due to the assumed correlation between dietary sweetness and sugars intake. Descriptive data summarizing patterns and trends in the overall sweetness of the diet may help inform dietary recommendations. For this cross-sectional study, dietary information was collected from 15,655 participants aged ≥1.5 year, as part of the National Diet and Nutrition Survey Rolling Programme (NDNS RP) over the course of four consecutive days between 2008/09 and 2018/19. Products that were sweetened with LCS were matched to their sugar-sweetened equivalents (e.g., a regular beverage with sugars and a diet beverage with LCS). The amount of sweetness in an individual’s diet was quantified in terms of grams of ASE (approximate sugar equivalent) per day. During the study period, the ASE of the diet declined by approximately 10%. The estimated ASE of the diet per 2000 calories was 96.7 g/d for children and 113.8 g/d for adults. Approximately one-fifth of the total ASE was from LCSs. There was evidence of a non-linear trend over time, with ASE levels remaining relatively stable between 2008/09 and 2014/15, and then declining. The amount of ASE coming from LCS sources increased, going from 8g/d to 12.6 g/d. The overall change in total sugars and ASE was more apparent for beverages compared to foods (ASE values decreased by 20.7% for beverages vs. 4.4% for foods), but both decreased significantly. In the UK, there has been a shift in both the overall sweetness of the diet, as well as the total amount of sugars consumed. This is partly attributable to the reformulation of products, as well as changes in preferences among consumers. According to the findings of this study, the sweetness levels in the diets of the UK population are declining over time.