Abstract
This study aimed to assess the impact of a high-fiber/low-fat agrarian diet (AD) on inflammation and metabolic outcomes in HIV-positive men who have sex with men (MSM). Since the gut microbiomes of MSM resemble those of individuals in agrarian cultures, including being Prevotella-rich and Bacteroides-poor, we hypothesized that they would have particularly strong health benefits from consumption of a diet matched to their microbiome type. Sixty-six participants, including 36 HIV-positive MSM [HIV(+)MSM], 21 HIV-negative MSM, and 9 HIV-negative men who have sex with women, were randomized to either an AD or a high-fat/low-fiber western diet (WD) for 4 weeks. Plasma, fecal, and colonic biopsy samples were obtained. Metabolic and inflammatory markers were measured in plasma. 16S ribosomal RNA sequencing was performed on fecal and biopsy samples, and shotgun metagenomic sequencing was performed on fecal samples. The AD reduced plasma low-density lipoprotein cholesterol (LDL-C) in HIV(+)MSM, with median reductions of 0.4138 mmoL/L at 2 weeks and 0.2845 mmol/L at 4 weeks. Greater LDL-C reductions were predicted by Prevotella-rich/Bacteroides-poor microbiomes with increased starch utilization potential, emphasizing the importance of personalized microbiome-dietary matching. The AD also reduced T cell exhaustion and pro-inflammatory intermediate monocytes and altered host transcription in the colonic mucosa. IMPORTANCE: Our findings suggest tailoring diet interventions to baseline microbiome types can promote metabolic health in Prevotella-rich/Bacteroides-poor MSM, a significant portion of people living with HIV at risk for metabolic syndrome.This study was registered at NCT02610374.