人体肠道内数以万亿计的微生物通过将复杂碳水化合物分解为脂肪酸，为人体提供约10%的热量，同时合成维生素K及多种B族维生素，调节免疫系统并促进血清素等信号分子的生成。科学研究表明，维持肠道菌群多样性的最佳途径是保持多样化饮食。2018年的一项美国公民科学项目显示，每周摄入30种植物的人群其菌群多样性显著高于每周摄入少于10种的人；斯坦福大学2021年的研究也证实，泡菜和酸菜等发酵食品能有效提高菌群多样性。
然而，许多追求定制化方案的消费者转向直接面向消费者（D2C）的检测公司。这类公司通过测定粪便样本中的DNA和RNA提供菌群分析、定制食谱、活菌补剂及特制膳食补充剂。但这种定制干预面临科学挑战，因为人体并不存在统一的“标准”健康菌群参考模型，不同结构的菌群同样能保持良好功能。目前缺乏充分的公开发表研究证实微调特定菌种能显著改善健康，且多数D2C公司拒绝公开其专有数据，尽管英国Zoe等少数机构参与同行评议研究并显示定制饮食仅产生微弱的边际效应。
D2C检测本身的准确性也备受质疑。美国国家标准与技术研究院（NIST）将21份完全同质化的相同粪便样本分别寄送给7家D2C公司进行测试（每家3份）。2月份公布的结果显示，不仅不同公司之间的检测结果存在显著差异，甚至同一家公司对相同样本的多次分析也出现了严重不一致。加州大学戴维斯分校的专家指出，个性化微生物组医学的商业宣称多属夸大其词，消费者与其斥巨资购买定制检测，不如坚持摄入发酵食品与多样化植物饮食。
Trillions of microorganisms inhabiting the human gut digest complex carbohydrates into fatty acids providing approximately 10% of caloric intake, while synthesizing essential vitamins (including vitamin K and B-group vitamins) and regulating neurotransmitters like serotonin. Maintaining microbiome diversity is predominantly achieved through varied dietary habits. A 2018 American citizen-science initiative demonstrated that consuming 30 plant varieties weekly yielded significantly greater bacterial diversity than eating fewer than ten, while a 2021 Stanford University study confirmed that fermented foods such as kimchi and sauerkraut similarly enhance gut diversity.
Commercial direct-to-consumer (D2C) companies have capitalized on this interest by offering stool genomic testing (DNA and RNA analysis), tailored nutritional regimens, and specialized probiotic supplements. However, this approach lacks clinical grounding because there is no universal "ideal" microbiome baseline, and distinct microbial compositions can function effectively. The primary indicator of poor gut health is a general deficit in biodiversity rather than the absence of specific microbes; consequently, targeted microbial adjustments lack rigorous published scientific backing, with peer-reviewed data from firms like Britain's Zoe demonstrating only marginal benefits.
Furthermore, the analytical reliability of commercial testing remains deeply flawed. A benchmarking study by America's National Institute of Standards and Technology distributed 21 homogenized, identical fecal samples across seven D2C testing firms (three samples each). The findings, published in February, revealed striking discrepancies not only across different commercial providers but also between repeated analyses within the same individual company. Experts caution that most commercial claims regarding bespoke microbiome medicine are unfounded, making regular consumption of fermented foods and diverse fiber a vastly more cost-effective strategy.
Source: Can you hack your gut microbiome?
Subtitle: Yes. But perhaps best not to overthink it
Dateline: 8月 13, 2026 04:20 上午