Design of the Building Research in CRC prevention (BRIDGE-CRC) trial: a 6-month, parallel group Mediterranean diet and weight loss randomized controlled lifestyle intervention targeting the bile acid-gut microbiome axis to reduce colorectal cancer risk among African American/Black adults with obesity.

BACKGROUND: Among all racial/ethnic groups, people who identify as African American/Blacks have the second highest colorectal cancer (CRC) incidence in the USA. This disparity may exist because African American/Blacks, compared to other racial/ethnic groups, have a higher prevalence of risk factors for CRC, including obesity, low fiber consumption, and higher intakes of fat and animal protein. One unexplored, underlying mechanism of this relationship is the bile acid-gut microbiome axis. High saturated fat, low fiber diets, and obesity lead to increases in tumor promoting secondary bile acids. Diets high in fiber, such as a Mediterranean diet, and intentional weight loss may reduce CRC risk by modulating the bile acid-gut microbiome axis. The purpose of this study is to test the impact of a Mediterranean diet alone, weight loss alone, or both, compared to typical diet controls on the bile acid-gut microbiome axis and CRC risk factors among African American/Blacks with obesity. Because weight loss or a Mediterranean diet alone can reduce CRC risk, we hypothesize that weight loss plus a Mediterranean diet will reduce CRC risk the most. METHODS: This randomized controlled lifestyle intervention will randomize 192 African American/Blacks with obesity, aged 45-75 years to one of four arms: Mediterranean diet, weight loss, weight loss plus Mediterranean diet, or typical diet controls, for 6 months (48 per arm). Data will be collected at baseline, mid-study, and study end. Primary outcomes include total circulating and fecal bile acids, taurine-conjugated bile acids, and deoxycholic acid. Secondary outcomes include body weight, body composition, dietary change, physical activity, metabolic risk, circulating cytokines, gut microbial community structure and composition, fecal short-chain fatty acids, and expression levels of genes from exfoliated intestinal cells linked to carcinogenesis. DISCUSSION: This study will be the first randomized controlled trial to examine the effects of a Mediterranean diet, weight loss, or both on bile acid metabolism, the gut microbiome, and intestinal epithelial genes associated with carcinogenesis. This approach to CRC risk reduction may be especially important among African American/Blacks given their higher risk factor profile and increased CRC incidence. TRIAL REGISTRATION: ClinicalTrials.gov NCT04753359 . Registered on 15 February 2021.

Efficacy of behavioral interventions to improve maternal mental health and breastfeeding outcomes: a systematic review.

BACKGROUND: Despite extensive benefits and high intentions, few mothers breastfeed exclusively for the recommended duration. Maternal mental health is an important underlying factor associated with barriers and reduced rates of breastfeeding intent, initiation, and continuation. Given evidence of a bidirectional association between maternal mental health and breastfeeding, it is important to consider both factors when examining the efficacy of interventions to improve these outcomes. The purpose of this manuscript is to review the literature on the efficacy of behavioral interventions focused on both maternal mental health and breastfeeding outcomes, examining the intersection of the two. METHODS: This systematic review was completed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) reporting guidelines. Studies were selected if they were available in English, used primary experimental design, and used a behavioral intervention type to examine maternal mental health and breastfeeding outcomes. Articles were identified from PubMed, CINAHL, Embase, and PsycINFO from database inception to 3 March 2022. Study quality was assessed using the Cochrane Risk of Bias tool. Results were synthesized by intervention success for 1. Mental health and breastfeeding, 2. Breastfeeding only, 3. Mental health only, and 4. No intervention effect. PROSPERO CRD42021224228. RESULTS: Thirty interventions reported in 33 articles were identified, representing 15 countries. Twelve studies reported statistically significant positive effect of the intervention on both maternal mental health and breastfeeding; most showing a decrease in self-report depressive and/or anxiety symptoms in parallel to an increase in breastfeeding duration and/or exclusivity. Common characteristics of successful interventions were a) occurring across pregnancy and postpartum, b) delivered by hospital staff or multidisciplinary teams, c) offered individually, and d) designed to focus on breastfeeding and maternal mental health or on breastfeeding only. Our results are not representative of all countries, persons, experiences, circumstances, or physiological characteristics. CONCLUSIONS: Interventions that extend the perinatal period and offer individualized support from both professionals and peers who collaborate through a continuum of settings (e.g., health system, home, and community) are most successful in improving both mental health and breastfeeding outcomes. The benefits of improving these outcomes warrant continued development and implementation of such interventions. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42021224228.

Feasibility of a Web-Based Intervention to Prevent Perinatal Depression and Promote Human Milk Feeding: Randomized Pilot Trial.

BACKGROUND: Mothers who identify as Black or African American are more likely to report depressed moods in late pregnancy and early postpartum and have the lowest rates of human milk feeding compared with all other racial groups in the United States. Internet interventions offer the potential to extend preventative and supportive services as they address key barriers, particularly for those navigating the complex and vulnerable early postpartum period. However, there is limited evidence on the feasibility of such interventions for preventing perinatal mental health disorders and improving human milk feeding outcomes in Black mothers. OBJECTIVE: This pilot study aimed to assess the feasibility and preliminary findings of a web-based cognitive behavioral therapy-based internet intervention, with and without human milk feeding education and support, to prevent perinatal depression and promote human milk feeding in Black mothers. METHODS: Participants were Black-identifying individuals between 20 and 28 weeks of pregnancy with human milk feeding intention and mild to moderate depressive symptoms (Patient Health Questionnaire scores 5-14). Participants were randomized to either Sunnyside, a 6-week cognitive behavioral therapy-based web-based intervention, or Sunnyside Plus, which included additional education and support to promote human milk feeding. Assessments occurred at baseline, third trimester (end of antenatal treatment), 6 weeks postpartum (end of postpartum treatment), and 12 weeks postpartum. The primary focus of this randomized pilot trial was the feasibility and preliminary outcomes of mental health and human milk feeding. RESULTS: A total of 22 tertiary-educated participants were randomized. The mean number of log-ins was 7.3 (SD 5.3) for Sunnyside and 13.8 (SD 10.5) for Sunnyside Plus. Scores of depression and anxiety measures remained below the clinical threshold for referral to treatment in both groups. All the participants initiated human milk feeding (18/18, 100%). Most participants reported at least some human milk feeding at both 6 and 12 weeks postpartum (6/7, 86%; 11/11, 100%, or 10/10, 100%, for Sunnyside and Sunnyside Plus, respectively). CONCLUSIONS: The results suggest that tertiary-educated Black mothers at risk for perinatal depression and who intended to human milk feed were receptive to and satisfied with a web-based cognitive behavioral therapy-based internet intervention, with and without human milk feeding education and support. Preliminary findings indicate that both Sunnyside and Sunnyside Plus interventions have the potential to affect symptoms of depression, anxiety, and human milk feeding outcomes. TRIAL REGISTRATION: ClinicalTrials.gov NCT04128202; https://www.clinicaltrials.gov/ct2/show/NCT04128202.

Bile Acids, Gut Microbes, and the Neighborhood Food Environment-a Potential Driver of Colorectal Cancer Health Disparities.

Bile acids (BAs) facilitate nutrient digestion and absorption and act as signaling molecules in a number of metabolic and inflammatory pathways. Expansion of the BA pool and increased exposure to microbial BA metabolites has been associated with increased colorectal cancer (CRC) risk. It is well established that diet influences systemic BA concentrations and microbial BA metabolism. Therefore, consumption of nutrients that reduce colonic exposure to BAs and microbial BA metabolites may be an effective method for reducing CRC risk, particularly in populations disproportionately burdened by CRC. Individuals who identify as Black/African American (AA/B) have the highest CRC incidence and death in the United States and are more likely to live in a food environment with an inequitable access to BA mitigating nutrients. Thus, this review discusses the current evidence supporting diet as a contributor to CRC disparities through BA-mediated mechanisms and relationships between these mechanisms and barriers to maintaining a low-risk diet.

Current Evidence and Directions for Intermittent Fasting During Cancer Chemotherapy.

Almost 40% of the adult population in the USA will be diagnosed with cancer in their lifetime. Diet is a modifiable factor which is known to affect cancer risk and recurrence. Yet, little is known about how diet influences cancer treatment outcomes. Intermittent fasting, characterized by periods of abstaining from foods and beverages alternated with periods of ad libitum intake, when adopted in the context of chemotherapy, has shown promise in preclinical models resulting in decreased vomiting, diarrhea, visible discomfort, and improved insulin sensitivity and efficacy of chemotherapeutic treatment. Although intermittent fasting during receipt of chemotherapy has been well-established in preclinical models, limited numbers of human studies are now being reported. This review aims to survey the current data examining the effect of intermittent fasting on chemotherapy efficacy, patient treatment outcomes, patient centered outcomes, and circulating biomarkers associated with cancer. Available data show that periodic fasting, a form of intermittent fasting, may hold potential to improve the effectiveness of chemotherapy, decrease treatment-related side effects and cancer-promoting factors such as insulin, while ameliorating treatment-related decreases in quality of life and daily functioning. Larger controlled periodic fasting trials, including exploration of alternate forms of intermittent fasting, are needed to better elucidate the effect of intermittent fasting on treatment and patient outcomes during chemotherapy.

Effect of time restricted feeding on the gut microbiome in adults with obesity: A pilot study.

BACKGROUND: Time restricted feeding is a form of intermittent fasting where participants shorten the daily window in which they eat. AIM: This is the first study to examine the effects of intermittent fasting on changes in the gut microbiome. METHODS: Adults with obesity (n = 14) participated in a daily 8-hour time restricted feeding intervention (8-hour feeding window/16-hour fasting window) for 12 weeks. Fecal microbiota were determined by 16 S rRNA (ribosomal ribonucleic acid) gene sequencing of stool samples. RESULTS: Body weight decreased (P < 0.05) by -2 ± 1 kg. Gut microbiota phylogenetic diversity remained unchanged. The two most common phyla were Firmicutes and Bacteroidetes accounting for 61.2% and 26.9% of total abundance at baseline. No significant alterations in the abundance of Firmicutes, Bacteroidetes, or any other phyla were detected after 12 weeks of time restricted feeding. CONCLUSIONS: Time restricted feeding did not significantly alter the diversity or overall composition of the gut microbiome.