一篇 2024 年发表在 Science 上的论文显示,工业化社会的人类已经失去了降解纤维素的肠道细菌,因此现代人的肠道"从来就不是为消化纤维素而构造的",也不再具备发酵植物细胞壁的机制。
原始表述
无阿拉伯语原文。
译文
一篇 2024 年发表在 Science 上的论文显示,工业化社会的人类已经失去了降解纤维素的肠道细菌,因此现代人的肠道"从来就不是为消化纤维素而构造的",也不再具备发酵植物细胞壁的机制。
出处
- 来源状态
- 档案网站编辑
- 归属
- Archive editors
- 出处
- https://eltayebat.com/rule/leafy-greens-cucurbits/
- 归属的不确定性
- Archive featured card and narrative on Moraïs et al. 2024; presented as 'the deepest support for Dr. Diaa's ruminant argument'.
- 所声称的机制
Loss of cellulosome-producing Ruminococcus species.
- 所声称的健康影响
Inability to ferment plant cell walls.
- 涉及人群
Industrialised populations
- Elawady 设定的地域限制
none found
科学评估
基本错误 – 该说法的主要部分没有证据支持,或被严重夸大。
证据确定性: 中 – 进一步研究仍可能影响该评估。
1. 说法是什么?
Modern humans lack microbes to ferment cellulose, so vegetables are the wrong fuel.
2. 哪些内容可证实是正确的?
Correctly reported: cellulosome-producing ruminococci are abundant in hunter-gatherers, rural and ancient populations and rare in industrialised societies; one species likely came from ruminants.
3. 哪些内容是错误或夸大的?
The paper is titled 'Cryptic diversity of cellulose-degrading gut bacteria in industrialized humans', i.e. such bacteria exist in industrialised humans, although rarely. Cellulose is only one component of plant fibre; pectins, hemicelluloses, inulin and resistant starch are fermented by many common gut bacteria. The paper says nothing about vegetables being harmful. The authors report these species in at most 4.6% of industrialised samples versus about 20-43% in non-industrialised and ancient samples, attribute their rarity to the westernised lifestyle, and suggest re-introducing them through targeted diets and specialised probiotics - the opposite of the inference that humans are not built to digest plant fibre. If anything, the authors interpret the loss as a consequence of the westernised lifestyle, which suggests that higher plant-fibre intake supports these microbes.
4. 哪些内容仍不明确?
Whether low abundance of cellulose degraders has health consequences is unknown.
5. 哪些研究支持该说法?
None for the archive's conclusion.
6. 哪些研究与该说法相矛盾?
Moraïs 2024 abstract itself; controlled feeding studies in US adults showing 42-70% apparent digestion of cellulose from fruits and vegetables (Slavin 1981, I-VEG-129; Kelsay 1981, I-VEG-130); microbes degrading spinach cell walls found in all French volunteers tested (Chassard 2010, I-VEG-131); Koh 2016; Reynolds 2019.
7. 对德国和欧洲而言情况如何?
Applies to industrialised populations including Germany.
8. 关于埃及的已知情况是什么?
Not specific.
9. 合理的实际结论是什么?
这项研究涉及的是微生物组生态学;它并不支持避免吃蔬菜。
评估详情
- 证据确定性的依据
The paper's abstract states that humans, like all mammals, depend on the gut microbiome for cellulose digestion and that cellulose-degrading species are present but rare in industrialised populations; it does not show that the gut cannot ferment other plant cell-wall fibres, and it does not study health effects of eating vegetables.
- 来源质量
High-quality basic-science paper; archive interpretation goes beyond the findings.
- 地区可推广性
The finding concerns industrialised populations (including Germany); rural Egyptian populations were not specifically mentioned in the abstract.
- 个体例外情况
Not applicable.
- 说法的地域范围
- 未说明
- 最近审核
- 2026年10月26日 初步
科学证据详解
已被科学证据否定 – 高质量证据显示情况恰恰相反,或该说法与已确立的生理学知识相矛盾。
研究问题: Does the 2024 Science paper (Moraïs et al.) show that industrialised humans lack the microbial machinery to ferment cellulose and plant cell walls?
研究问题详解 (PECO)
- 人群
- Industrialised human populations
- 干预或暴露
- Industrialised lifestyle / low-fibre diet
- 对照
- Non-industrialised and ancient populations
- 地域范围
- universal biology; microbiome composition varies with lifestyle
- 结局指标
- presence of cellulose-degrading microbes
- fermentation of plant cell walls
研究结果按作者报告呈现。我们的评估见下文。
哪些证据支持该说法?
Cellulose-digesting gut bacteria
Moraïs 2024 (Science), full text in register.
- 实际结果
- Cellulosome-producing ruminococci in at most 4.6% of industrialised samples vs 20-43% in rural, hunter-gatherer and ancient samples.
- 方法学质量
- high (large metagenomic analysis + biochemistry)
- 相关性
- direct for the "rare in industrialised people" part only
- 局限
- Does not test fermentation capacity of the whole microbiome or health effects.
哪些证据不支持该说法?
Every person tested had gut microbes that break down spinach cell walls
Chassard C et al.. FEMS Microbiol Ecol 2010 · PMID 20662929 · DOI 10.1111/j.1574-6941.2010.00941.x 其他已核查摘要新增Chassard 2010: culture and qPCR of human faecal cellulose degraders.
- 实际结果
- Spinach cell-wall degrading microorganisms present in all individuals (French volunteers); taxa differ by methane status.
- 方法学质量
- moderate
- 相关性
- direct
- 局限
- Small lab study.
Humans ferment much of the cellulose in vegetables
Slavin 1981 controlled feeding (US).
- 实际结果
- ~70% of cellulose from a mixed fruit/vegetable diet disappeared.
- 方法学质量
- moderate
- 相关性
- direct
- 局限
- n = 7.
Cellulose-digesting gut bacteria
The archive's own source.
- 实际结果
- Title and abstract describe cellulose degraders IN industrialised humans; authors attribute rarity to westernised low-fibre lifestyle and suggest restoring them via diet.
- 方法学质量
- high
- 相关性
- direct
- 局限
- n/a
总体证据说明了什么?
基于上述研究的编辑评估——其本身并非研究结果。
哪种观点有更好的证据支持?
Cellulosome-producing ruminococci have become rare in industrialised populations, but other cellulose and cell-wall degraders (e.g. Bacteroidetes) are present, and controlled feeding studies show substantial fermentation of vegetable cellulose in industrialised adults.
为什么有些研究权重更大
The archive's source is high quality but answers a narrower question (prevalence of one bacterial group); direct fermentation and culture studies answer the claim's question.
因果关系是否已确立? 不适用 Interpretation claim about a study.
仍存在的不确定性
Health consequences of losing cellulosome-producing ruminococci.
合理的结论
The archive correctly reports the rarity finding but draws the wrong conclusion; the paper and other studies show that modern human guts still ferment plant cell walls.
为什么研究结果看起来互相矛盾?
Moraïs 2024 (rarity of one bacterial group) and Slavin/Kelsay/Chassard (fermentation occurs) answer different questions and are compatible.
这是否取决于国家?
- 一般生物学效应
- Microbiome capacity differs by lifestyle, not by a fixed human design.
- 饮食习惯
- Higher-fibre traditional diets support fibre-degrading microbes.
- 食品原产地
- not applicable
- 污染物
- not applicable
- 本国生产条件
- not applicable
- 法律规则
- not applicable
- 实际监测数据
- not applicable
足以改变结论的地区差异没有可靠数据支持。
统计复核
- Cellulose fermented per day in industrialised adults – ~3.8 g/day (69.7% of 5.4 g). 已重新计算
总体证据的确定性(GRADE,简化版)
- 主要结局
- Capacity of industrialised human gut to ferment plant cell walls
- 起始等级
- 低(观察性研究)
- 降级理由
- imprecision
- 升级理由
- consistency across feeding studies and microbiology
- 结果
- 中
由单名审查者参照 GRADE 方法进行的简化评估;并非正式的 GRADE 专家组评估。GRADE 评价的是针对某一结局的整体证据,而非单项研究。
检索策略
本次审查的文献检索记录(检索式采用原数据库语法)。
| 数据库 | 日期 | 检索式 | 检索目标 | 命中数 | 纳入数 |
|---|---|---|---|---|---|
| PubMed | 2026年10月26日 | (cellulose) AND (human OR humans) AND (colon* OR fecal OR faecal OR gut) AND (degrad* OR digestib* OR ferment*) AND (Ruminococcus OR methanogen* OR "cellulolytic") | 双向 | 46 |
待解决的问题
Whether reintroducing cellulolytic ruminococci has health effects.
核查深度如何?
6 项相关研究:1 项核查了全文(其中 1 项进行了结构化偏倚风险评估),5 项基于摘要核查,0 项仅核查了文献信息。 尚未进行由两名独立审查者完成的正式评估,也尚未进行独立的人类专家审核。
最近一次科学审核: 2026年10月26日
评定结论的变更历史
- 2026年10月25日 · 第 1 阶段 · 初始评估: 基本错误 (中)
- 2026年10月26日 · 第 4 阶段(系统证据审查) · 在扩展证据后重新审查;评定结论不变: 基本错误 (中)
Direct human fermentation data strengthen the existing conclusion; the archive reproduces the rarity finding correctly, which keeps the verdict at MOSTLY_FALSE rather than FALSE.
新来源: I-VEG-129 I-VEG-130 I-VEG-131
通俗解释
档案网站引用一项 2024 年的研究,作为现代人无法消化植物纤维的证据。这项研究实际上在人体内发现了消化纤维素的细菌,它们在传统人群和农村人群中很常见,在工业化社会人群中则很罕见。它并未检验吃蔬菜是否有害。蔬菜中的许多其他类型的膳食纤维都能被常见的肠道细菌发酵,而这些微生物的减少本身可能反映了低纤维的西方饮食。
与该说法相关的研究
支持该说法的研究 (0)
该组中没有研究。
与该说法相矛盾或限制该说法的研究 (5)
-
How gut bacteria use fibre
Koh A et al.. Cell 2016 · PMID 27259147 · DOI 10.1016/j.cell.2016.05.041叙述性综述独立交叉核查已核查摘要Gut bacteria turn fibre into short-chain fatty acids that act as fuel and signals for the body.
该研究是否支持这一具体说法? 否 · 方法学质量: 中 · 证据确定性:见该说法的总体评估
研究通俗解读
- 研究人员想了解什么?
Explain SCFAs
- 研究是如何开展的?
Review
- 研究了多少人、动物或样本?
Not applicable
- 实际发现了什么?
SCFAs act on host physiology
- 观察到的效应有多大?
Not applicable
- 研究结果对日常生活意味着什么?
Fibre feeds beneficial processes.
- 该研究有哪些局限?
Mechanistic
- 它对 Elawady 的具体说法说明了什么?
Contradicts 'useless cellulose'
- 研究结果是否适用于德国和欧洲?
High
- 从该研究中明确不能得出什么结论?
Cannot quantify clinical benefit.
-
Fibre and health (Lancet 2019)
Reynolds A et al.. Lancet 2019 · PMID 30638909 · DOI 10.1016/S0140-6736(18)31809-9Meta分析独立交叉核查已核查摘要★ 关键研究High fibre intake is linked to 15-30% lower death and disease rates; trials show better weight, blood pressure and cholesterol.
该研究是否支持这一具体说法? 否 · 方法学质量: 高 · 证据确定性:见该说法的总体评估
研究通俗解读
- 研究人员想了解什么?
Fibre and NCDs
- 研究是如何开展的?
Meta-analyses
- 研究了多少人、动物或样本?
185 cohorts, 58 RCTs
- 实际发现了什么?
Large benefits
- 观察到的效应有多大?
15-30% lower risk
- 研究结果对日常生活意味着什么?
Eat 25-29 g fibre daily.
- 该研究有哪些局限?
Observational endpoints
- 它对 Elawady 的具体说法说明了什么?
Contradicts 'cattle food'
- 研究结果是否适用于德国和欧洲?
High
- 从该研究中明确不能得出什么结论?
Not specific to leafy greens.
-
Humans ferment much of the cellulose in vegetables
Slavin JL et al.. J Nutr 1981 · PMID 6257867 · DOI 10.1093/jn/111.2.287其他独立交叉核查已核查摘要★ 关键研究In 7 women on controlled diets, about 70% of cellulose from fruits and vegetables was broken down in the gut, but only 8-16% of purified cellulose.
Industrialised (US) adults fermented most vegetable cellulose.
该研究是否支持这一具体说法? 否 · 方法学质量: 中 · 证据确定性:见该说法的总体评估
研究通俗解读
- 研究人员想了解什么?
Measure fibre digestibility in humans.
- 研究是如何开展的?
Controlled feeding.
- 研究了多少人、动物或样本?
7 women.
- 实际发现了什么?
Plant-food cellulose ~70% digested; purified cellulose little.
- 观察到的效应有多大?
69.7% vs 15.7%.
- 研究结果对日常生活意味着什么?
Gut bacteria break down much of the cellulose in vegetables.
- 该研究有哪些局限?
Very small; old methods.
- 它对 Elawady 的具体说法说明了什么?
Contradicts the claim.
- 研究结果是否适用于德国和欧洲?
Applicable.
- 从该研究中明确不能得出什么结论?
Cannot measure health effects.
-
Vegetable cellulose partly broken down in men
Kelsay JL et al.. Am J Clin Nutr 1981 · PMID 6269418 · DOI 10.1093/ajcn/34.9.1849其他独立交叉核查已核查摘要★ 关键研究In 12 men eating fruits and vegetables, 42% of cellulose and 88% of hemicellulose were broken down in the gut.
Industrialised adults fermented a substantial share of vegetable cellulose.
该研究是否支持这一具体说法? 否 · 方法学质量: 中 · 证据确定性:见该说法的总体评估
研究通俗解读
- 研究人员想了解什么?
Measure fibre fractions' digestibility.
- 研究是如何开展的?
Controlled feeding.
- 研究了多少人、动物或样本?
12 men.
- 实际发现了什么?
Cellulose 42%, hemicellulose 88%.
- 观察到的效应有多大?
See results.
- 研究结果对日常生活意味着什么?
Gut microbes use a large part of vegetable fibre.
- 该研究有哪些局限?
Small; old methods.
- 它对 Elawady 的具体说法说明了什么?
Contradicts the claim.
- 研究结果是否适用于德国和欧洲?
Applicable.
- 从该研究中明确不能得出什么结论?
Cannot measure health effects.
-
Every person tested had gut microbes that break down spinach cell walls
Chassard C et al.. FEMS Microbiol Ecol 2010 · PMID 20662929 · DOI 10.1111/j.1574-6941.2010.00941.x其他独立交叉核查已核查摘要French researchers found bacteria able to degrade spinach cell walls in all volunteers, of different types depending on methane production.
Spinach cell-wall degraders found in all individuals; different taxa by methane status.
该研究是否支持这一具体说法? 否 · 方法学质量: 中 · 证据确定性:见该说法的总体评估
研究通俗解读
- 研究人员想了解什么?
Characterise human cellulose degraders.
- 研究是如何开展的?
Culture and PCR.
- 研究了多少人、动物或样本?
Volunteers (n not in abstract).
- 实际发现了什么?
Degraders present in all.
- 观察到的效应有多大?
Not applicable.
- 研究结果对日常生活意味着什么?
Modern European guts can ferment vegetable cell walls.
- 该研究有哪些局限?
Small lab study.
- 它对 Elawady 的具体说法说明了什么?
Contradicts the claim.
- 研究结果是否适用于德国和欧洲?
European.
- 从该研究中明确不能得出什么结论?
Cannot quantify fermentation in vivo.
该组中没有被标记为关键研究的研究。
结果不一或不明确的研究 (1)
-
Cellulose-digesting gut bacteria
Moraïs S et al.. Science 2024 · PMID 38484069 · DOI 10.1126/science.adj9223其他被 Tayebat 档案网站引用全文,含结构化偏倚风险评估★ 关键研究Humans carry cellulose-digesting bacteria; they are common in traditional populations and rare in industrialised ones.
该研究是否支持这一具体说法? 否 · 方法学质量: 高 · 证据确定性:见该说法的总体评估
研究通俗解读
- 研究人员想了解什么?
Map cellulose degraders
- 研究是如何开展的?
Metagenomics + biochemistry
- 研究了多少人、动物或样本?
Not stated
- 实际发现了什么?
Rare in industrialised humans
- 观察到的效应有多大?
Not applicable
- 研究结果对日常生活意味着什么?
Western lifestyle may reduce these microbes.
- 该研究有哪些局限?
No health data
- 它对 Elawady 的具体说法说明了什么?
Does not support avoiding vegetables
- 研究结果是否适用于德国和欧洲?
Moderate
- 从该研究中明确不能得出什么结论?
Cannot show vegetables are harmful.
该组中没有被标记为关键研究的研究。
地区背景
德国 / 欧盟
Applies to industrialised populations including Germany.
埃及
Not specific.
在我的国家适用什么?
一般科学评估
基本错误 这项研究被误读了:它记录的是降解纤维素的细菌变得罕见,而不是消失;其他研究显示,现代人的肠道微生物仍能发酵蔬菜中的大部分纤维素。
以下食品安全领域与该说法相关:
- 农药与农药残留
- 污染物(重金属、PFAS、PCB、二噁英、硝酸盐)
- 病原体(沙门氏菌、弯曲杆菌等)
水果与蔬菜
选择一个国家,查看针对该国已核查的信息。
局限:法律规则描述的是允许什么,而不是每一种食品实际含有什么。检测数据来自样本,只有结合其方法细节才有意义。
参考文献
- From Dietary Fiber to Host Physiology: Short-Chain Fatty Acids as Key Bacterial Metabolites.. Koh A et al.. Cell 2016 · PMID 27259147 · DOI 10.1016/j.cell.2016.05.041
- Carbohydrate quality and human health: a series of systematic reviews and meta-analyses.. Reynolds A et al.. Lancet 2019 · PMID 30638909 · DOI 10.1016/S0140-6736(18)31809-9
- Neutral detergent fiber, hemicellulose and cellulose digestibility in human subjects.. Slavin JL et al.. J Nutr 1981 · PMID 6257867 · DOI 10.1093/jn/111.2.287
- Effect of fiber from fruits and vegetables on metabolic responses of human subjects: fiber intakes, fecal excretions, and apparent digestibilities.. Kelsay JL et al.. Am J Clin Nutr 1981 · PMID 6269418 · DOI 10.1093/ajcn/34.9.1849
- The cellulose-degrading microbial community of the human gut varies according to the presence or absence of methanogens.. Chassard C et al.. FEMS Microbiol Ecol 2010 · PMID 20662929 · DOI 10.1111/j.1574-6941.2010.00941.x
- Cryptic diversity of cellulose-degrading gut bacteria in industrialized humans.. Moraïs S et al.. Science 2024 · PMID 38484069 · DOI 10.1126/science.adj9223