Impact of energy restriction of ultra-processed foods on the intestinal microbiota of individuals with obesity

The study aimed to evaluate the impact of recommended energy restriction of ultra-processed foods compared to generic energy restriction on the intestinal microbiota of individuals with obesity. The randomized clinical trial lasted six months and involved 43 adult individuals (19-60 years old), of both sexes, with obesity, and who wanted to lose weight. Participants were randomly divided into two groups: those in the intervention group received a diet with specific energy restriction for ultra-processed foods, limiting their consumption to less than 5% of total daily energy, while participants in the control group received a diet with generic energy restriction, with no specific focus on reducing ultra-processed foods, prioritizing the reduction of food portions in general. For analysis of the intestinal microbiota, a stool collection kit was provided for self-collection and subsequent sending to the company BiomeHub. In the laboratory, amplicon sequencing analyses of the 16S rRNA gene (v3/v4 region) were performed to identify the bacteria present in the samples. After sequencing, the Firmicutes/Bacteroidetes ratio, richness, alpha diversity (Shannon, Simpson and Inverse Simpson indexes) and beta diversity, using the Bray-Curtis index, among other parameters, were analyzed. These analyses allowed a detailed assessment of changes in the microbiota composition throughout the study.

本研究旨在评估相较于通用能量限制方案，超加工食品（ultra-processed foods）推荐能量限制方案对肥胖人群肠道菌群的影响。本随机对照临床试验（randomized clinical trial）为期六个月，共纳入43名年龄19至60岁、患有肥胖且有减重需求的成年男女受试者。受试者被随机分为两组：干预组受试者接受针对超加工食品的专属能量限制饮食，将其每日总能量摄入占比控制在5%以下；对照组受试者则接受通用能量限制饮食，未特别针对超加工食品进行限制，而是以整体减少食物分量为优先原则。为开展肠道菌群分析，研究人员为受试者提供了粪便采集套件，用于自行采样后寄送至BiomeHub公司。实验室层面，研究人员针对16S rRNA基因（v3/v4区域）开展扩增子测序分析，以鉴定样本中存在的细菌。测序完成后，研究人员对多项参数展开分析，包括厚壁菌门/拟杆菌门比值、菌群丰富度、α多样性（香农、辛普森及逆辛普森指数）以及基于布雷-柯蒂斯（Bray-Curtis）指数的β多样性等。上述分析可对整个研究周期内肠道菌群组成的变化进行详细评估。