High-protein diets may be linked to gut inflammation due to increased production of hydrogen sulfide (H 2 S), a potential toxin, as an end product of microbial fermentation in the colon by sulfidogenic sulfatereducing bacteria (SRB). We hypothesized that dietary content of sulfur-containing amino acids (SAA) leads to variation in the relative abundances of intestinal SRB, which include Desulfovibrio and Bilophila taxa. To test this hypothesis we performed a pilot crossover study in four healthy volunteers, who consumed two interventional diets for 10-14 days, containing high or low SAA content. The total energy intake was similar between the two dietary extremes. Microbial communities were characterized by 16S rRNA gene amplicon and shotgun next-generation DNA sequencing. While the relative abundance of Desulfovibrio differed among participants (ANOVA P= 0.001), we could not detect a change with dietary treatments. Similarly, no differences in Bilophila abundance were observed among individuals or dietary arms. Inter-personal differences in microbial community composition and functional gene categories differed between subjects and these differences were maintained over the course of the study. These observations are consistent with re-analysis of two previously published dietary intervention studies. Finally, we found that inter-personal differences in the taxonomic composition of fecal microbiota, including the relative abundances of SRB, were maintained over time in 19 healthy individuals in our stool donor program. These results suggest that the use of dietary interventions alone may be insufficient for rapid therapeutic targeting of SRB. Nevertheless, these pilot data provide a foundation to inform future, statistically powered, studies.

The findings of this descriptive analysis of postmenopausal women may help clinicians counsel women about expectations and treatment options to address menopause-associated symptoms and the relationship between postmenopausal symptoms and overall health.

Research and Nutrition Communications. She is responsible for developing and coordinating IFIC's consumer research efforts as well as nutrition science-focused communication programs. Marisa Paipongna, BS, is the Research and Nutrition Coordinator at IFIC where she supports the planning, implementation, and evaluation of IFIC's research and nutrition teams. Kristen Smith, PhD, RDN, LD, is the owner of K&T Consulting Services, LLC, providing nutrition consulting support as well as medical and technical writing services. The IFIC Food & Health Survey has been conducted by, and in partnership with, Greenwald Research since 2012.The International Food Information Council is a §501(c)(3) nonprofit educational organization supported by food, beverage, and agriculture companies. Its mission is to effectively communicate science-based information about health, nutrition, food safety, and agriculture. Dr Smith was a paid consultant of IFIC and participated in IFIC consumer data review and drafting of this article.