Hunger Training as a Self-regulation Strategy in a Comprehensive Weight Loss Program for Breast Cancer Prevention: A Randomized Feasibility Study.

Weight losses >10% favorably modulate biomarkers of breast cancer risk but are not typically achieved by comprehensive weight loss programs, including the Diabetes Prevention Program (DPP). Combining the DPP with hunger training (HT), an evidence-based self-regulation strategy that uses self-monitored glucose levels to guide meal timing, has potential to enhance weight losses and cancer-related biomarkers, if proven feasible. This two-arm randomized controlled trial examined the feasibility of adding HT to the DPP and explored effects on weight and metabolic and breast cancer risk biomarkers. Fifty postmenopausal women [body mass index (BMI) >27 kg/m2)] at risk of breast cancer were randomized to the DPP+HT or DPP-only arm. Both arms followed a 16-week version of the DPP delivered weekly by a trained registered dietitian. Those in the DPP+HT also wore a continuous glucose monitor during weeks 4-6 of the program. Feasibility criteria were accrual rates >50%, retention rates >80%, and adherence to the HT protocol >75%. All a priori feasibility criteria were achieved. The accrual rate was 67%, retention rate was 81%, and adherence to HT was 90%. Weight losses and BMI reductions were significant over time as were changes in metabolic and breast cancer risk biomarkers but did not vary by group. This trial demonstrated that HT was feasible to add to comprehensive weight management program targeted toward postmenopausal women at high risk of breast cancer, though upon preliminary examination it does not appear to enhance weight loss or metabolic changes. PREVENTION RELEVANCE: This study found that it was feasible to add a short glucose-guided eating intervention to a comprehensive weight management program targeting postmenopausal women at high risk of breast cancer. However, further development of this novel intervention as a cancer prevention strategy is needed.

Satiety does not affect neuroaffective electrophysiological responses to food-related or emotional visual cues.

Continuing to eat even when full leads to excessive calorie consumption and obesity. Thus, understanding brain responses to food cues when satiated has important implications for weight control interventions. We used the late positive potential (LPP, a component of the event-related potentials (ERP) indexing motivational relevance) to determine the extent to which satiety affects brain responses to images of highly palatable foods (high-fat, high-sugar), high and low motivationally relevant (pleasant, unpleasant) and neutral stimuli in a sample of obese (body mass index [BMI] ≥ 30 kg/m2) and lean (BMI < 25 kg/m2) individuals. Satiated individuals (N = 55, 21 with BMI ≥ 30 kg/m2) were fed a nutritional drink prior to the experimental session and were individually matched with 55 unsatiated individuals who saw the same images during a passive viewing task. Satiety did not affect LPP response to food-related or motivationally relevant cues in either BMI < 25 kg/m2 or BMI ≥ 30 kg/m2 individuals (p = .6). Irrespective of satiety, all participants showed larger LPPs as a function of the images' motivational relevance. There were no differences in LPP amplitude between BMI < 25 kg/m2 and BMI ≥ 30 kg/m2 individuals for any picture category, including food. However, within-group comparisons showed that BMI < 25 kg/m2 individuals had larger LPPs to low motivationally relevant pleasant images than to food-related cues (p < .001); this difference was not significant for BMI ≥ 30 kg/m2 individuals. Although satiety does not affect LPP responses to food-related cues, these results highlight the importance of evaluating reactivity to food-related cues in relation to other motivationally relevant stimuli. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Dietary inflammatory potential in relation to the gut microbiome: results from a cross-sectional study.

Diet has direct and indirect effects on health through inflammation and the gut microbiome. We investigated total dietary inflammatory potential via the literature-derived index (Dietary Inflammatory Index (DII®)) with gut microbiota diversity, composition and function. In cancer-free patient volunteers initially approached at colonoscopy and healthy volunteers recruited from the medical centre community, we assessed 16S ribosomal DNA in all subjects who provided dietary assessments and stool samples (n 101) and the gut metagenome in a subset of patients with residual fasting blood samples (n 34). Associations of energy-adjusted DII scores with microbial diversity and composition were examined using linear regression, permutational multivariate ANOVA and linear discriminant analysis. Spearman correlation was used to evaluate associations of species and pathways with DII and circulating inflammatory markers. Across DII levels, α- and ß-diversity did not significantly differ; however, Ruminococcus torques, Eubacterium nodatum, Acidaminococcus intestini and Clostridium leptum were more abundant in the most pro-inflammatory diet group, while Akkermansia muciniphila was enriched in the most anti-inflammatory diet group. With adjustment for age and BMI, R. torques, E. nodatum and A. intestini remained significantly associated with a more pro-inflammatory diet. In the metagenomic and fasting blood subset, A. intestini was correlated with circulating plasminogen activator inhibitor-1, a pro-inflammatory marker (rho = 0·40), but no associations remained significant upon correction for multiple testing. An index reflecting overall inflammatory potential of the diet was associated with specific microbes, but not overall diversity of the gut microbiome in our study. Findings from this preliminary study warrant further research in larger samples and prospective cohorts.

Dispensing apparatus for use in a cued food delivery task.

Neurobiological models of obesity postulate that obese individuals have difficulty regulating food intake partly because they attribute excessive salience to stimuli signaling food availability. Typically, human studies that investigate the relationship between brain responses to food-related stimuli and obesity present food cues without subsequent delivery of food. However, in order to identify the brain correlates of cue reactivity, we must record brain responses to food-related cues signaling food availability. Therefore, we have developed a dispensing apparatus for use in a cued-food delivery task in which event-related potentials (ERPs) to food-related images predicting food delivery and images not predicting food delivery can be recorded. Here, we describe a method where:•The experimental apparatus dispenses an edible item (i.e., a chocolate candy) which may or may not be eaten, or a non-edible control item (e.g., a plastic bead).•Deposit boxes are available to store uneaten candies and the non-edible control items.•The dispensing mechanism is capable of recording the exact timestamp when each delivery event occurs (e.g., release from the dispenser, arrival in the receptacle, storage in the deposit box).