A case-control study of the association between the gut microbiota and colorectal cancer: exploring the roles of diet, stress, and race.

BACKGROUND: The gut microbiota is associated with risk for colorectal cancer (CRC), a chronic disease for which racial disparities persist with Black Americans having a higher risk of CRC incidence and mortality compared to other groups. Given documented racial differences, the gut microbiota may offer some insight into previously unexplained racial disparities in CRC incidence and mortality. A case-control analysis comparing 11 women newly diagnosed with CRC with 22 cancer-free women matched on age, BMI, and race in a 1:2 ratio was conducted. Information about participants' diet and perceived stress levels were obtained via 24-h Dietary Recall and Perceived Stress Scale-10 survey, respectively. Participants provided stool samples from which microbial genomic DNA was extracted to reveal the abundance of 26 genera chosen a priori based on their previously observed relevance to CRC, anxiety symptoms, and diet. RESULTS: Significantly lower alpha diversity was observed among cancer-free Black women compared to all other race-cancer status combinations. No group differences were observed when comparing beta diversity. Non-Hispanic White CRC cases tended to have higher relative abundance of Fusobacteria, Gemellaceae, and Peptostreptococcus compared to all other race-cancer combination groups. Perceived stress was inversely associated with alpha diversity and was associated with additional genera. CONCLUSIONS: Our findings suggest that microbiome-CRC associations may differ by racial group. Additional large, racially diverse population-based studies are needed to determine if previously identified associations between characteristics of the gut microbiome and CRC are generalizable to Black women and other racial, ethnic, and gender groups.

Lifestyle interventions with dietary strategies after breast cancer diagnosis: a systematic review.

PURPOSE: Obesity can increase mortality and morbidity in breast cancer survivors. Healthy lifestyle factors such as diet can help manage weight in this population. This systematic review examined lifestyle interventions with dietary strategies for breast cancer survivors and their effect on diet and/or weight-related outcomes. METHODS: Searches were conducted in Ovid MEDLINE® ALL (1946-February 14, 2022), Embase (Elsevier), CINAHL Complete (EBSCO), and APA PsycArticles (EBSCO), using keywords for diet, breast cancer, and intervention. The search was limited to human studies, English language, and publication processing date 2016-2023. RESULTS: The search yielded 3427 articles. After title and abstract review, 225 full-text articles were screened, and 67 articles with 61 distinct samples and interventions met inclusion criteria. Of these 61 lifestyle interventions with dietary strategies, 43 interventions also addressed physical activity. Most studies were randomized controlled trials (n = 41) and conducted post-treatment (n = 45). Mean participant age was 54 years. Of 29 studies that reported race/ethnicity, 20 (69%) reported ≥50% White participants. Of 36 that reported dietary outcomes, 29 (81%) reported significant findings. Of 57 that reported weight-related outcomes, 51 (89%) reported significant findings. CONCLUSION: This review demonstrated promising evidence for the efficacy of lifestyle interventions with dietary strategies in breast cancer survivors. However, culturally tailored interventions and interventions conducted before and during treatment are lacking.

A case-control study of the association between the gut microbiota and colorectal cancer: exploring the roles of diet, stress, and race.

Background: The gut microbiota is associated with risk for colorectal cancer (CRC), a chronic disease for which racial disparities persist with Black Americans having a higher risk of CRC incidence and mortality compared to other groups. Given documented racial differences, the gut microbiota may offer some insight into previously unexplained racial disparities in CRC incidence and mortality. A case-control analysis comparing 11 women newly diagnosed with CRC with 22 cancer-free women matched on age, BMI, and race in a 1:2 ratio was conducted. Information about participants' diet and perceived stress levels were obtained via 24-hour Dietary Recall and Perceived Stress Scale-10 survey, respectively. Participants provided stool samples from which microbial genomic DNA was extracted to reveal the abundance of 26 genera chosen a priori based on their previously observed relevance to CRC, anxiety symptoms, and diet. Results: Significantly lower alpha diversity was observed among cancer-free Black women compared to all other race-cancer status combinations. No group differences were observed when comparing beta diversity. Non-Hispanic White CRC cases tended to have higher relative abundance of Fusobacteria, Gemellaceae, and Peptostreptococcus compared to all other race-cancer combination groups. Perceived stress was inversely associated with alpha diversity and was associated with additional genera. Conclusions: Our findings suggest that microbiome-CRC associations may differ by racial group. Additional large, racially diverse population-based studies are needed to determine if previously identified associations between characteristics of the gut microbiome and CRC are generalizable to Black women and other racial, ethnic, and gender groups.