Place · Level 3
Probiotics
全球年销 $70B+ · 但广谱益生菌概念几乎不成立 · 真正循证的只有几个菌株 + 几个适应症
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Story path
- 1ISAPP definition · strain mattersISAPP definition · strain matters
- 2Acid massacre · 0.01-1% surviveAcid massacre · 0.01-1% survive
- 3Evidence tiers · indication listEvidence tiers · indication list
- 4Fermented foods · daily probioticsFermented foods · daily probiotics
- 5FMT · the gold standardFMT · the gold standard
- 6Practical · should I / howPractical · should I / how
Chapter 1
ISAPP definition · strain matters
ISAPP definition · strain matters
The WHO/FAO 2002 + ISAPP 2014 official definition of a probiotic: 'live microorganisms that, when administered in adequate amounts, confer a health benefit on the host'.
Four key words in that definition; each one decides whether 99% of commercial products even qualify.
① 'Adequate live amount': most supplement labels show CFU (colony-forming units); clinically effective doses are typically 10⁹-10¹⁰ CFU/day. Critically, the manufacture-date count is not the end-of-shelf-life count — most strains lose viability over time and require refrigeration, dryness, or enteric coating. Spot checks routinely find labels claiming 10 billion CFU with only 1-10% remaining at end of shelf life.
② 'Strain' ≫ 'species': the species is *Lactobacillus rhamnosus*; the strain is *Lactobacillus rhamnosus* GG (LGG). Clinical effect is strain-specific — LGG has strong evidence for preventing pediatric acute diarrhea, but another strain of the same species may be completely useless. This is the root of the 'lactic acid bacteria' confusion: vendors say 'contains probiotics' without naming the strain, which usually means an inexpensive strain with no clinical data.
③ 'Confers a health benefit on the host': requires human RCT evidence for that strain + that specific indication. Not 'theoretically beneficial', not 'improves a biomarker' — clinically meaningful improvement in a defined disease or symptom.
④ 'Live': dead organisms aren't probiotics by definition, though the *postbiotic* concept is gaining ground. This is why hot water, acidic drinks, and high-heat cooking discount the probiotic value of fermented foods.
So to judge whether the bottle on your shelf is real, check three things:
1. Does it name a specific strain (LGG / BB-12 / DSM xxxxx, etc.)?
2. Does that strain have an RCT for your indication?
3. Is the labeled CFU the minimum at end of shelf life, or just the manufacture-date number?
Four key words in that definition; each one decides whether 99% of commercial products even qualify.
① 'Adequate live amount': most supplement labels show CFU (colony-forming units); clinically effective doses are typically 10⁹-10¹⁰ CFU/day. Critically, the manufacture-date count is not the end-of-shelf-life count — most strains lose viability over time and require refrigeration, dryness, or enteric coating. Spot checks routinely find labels claiming 10 billion CFU with only 1-10% remaining at end of shelf life.
② 'Strain' ≫ 'species': the species is *Lactobacillus rhamnosus*; the strain is *Lactobacillus rhamnosus* GG (LGG). Clinical effect is strain-specific — LGG has strong evidence for preventing pediatric acute diarrhea, but another strain of the same species may be completely useless. This is the root of the 'lactic acid bacteria' confusion: vendors say 'contains probiotics' without naming the strain, which usually means an inexpensive strain with no clinical data.
③ 'Confers a health benefit on the host': requires human RCT evidence for that strain + that specific indication. Not 'theoretically beneficial', not 'improves a biomarker' — clinically meaningful improvement in a defined disease or symptom.
④ 'Live': dead organisms aren't probiotics by definition, though the *postbiotic* concept is gaining ground. This is why hot water, acidic drinks, and high-heat cooking discount the probiotic value of fermented foods.
So to judge whether the bottle on your shelf is real, check three things:
1. Does it name a specific strain (LGG / BB-12 / DSM xxxxx, etc.)?
2. Does that strain have an RCT for your indication?
3. Is the labeled CFU the minimum at end of shelf life, or just the manufacture-date number?
定义 · 拆成四个词看
官方定义只有一句话, 但它是一把筛子: 拆成四个词, 货架上绝大多数瓶子当场出局。WHO/FAO 2002 + ISAPP 2014 给 probiotic 的官方定义是: 给予足量活菌, 对宿主健康产生有益作用的微生物。
这个定义里有四个关键字, 每个都决定 99% 的商业产品是否够格。
① 足量活菌 (sufficient live): 多数补剂标签写 CFU (colony forming units, 集落形成单位), 临床有效剂量通常在 10⁹-10¹⁰ CFU/天。关键是出厂时的含量不等于货架期末的含量, 大多数菌活力随时间衰减, 需要冷藏、干燥保护或肠溶包衣。抽检里常见的情况是: 标签写 100 亿 CFU, 货架末实测只剩 1-10%。
② 菌株 (strain) 远比菌种 (species) 重要: 种 是 Lactobacillus rhamnosus, 株 是 Lactobacillus rhamnosus GG (LGG)。临床效果是菌株特异的——LGG 防儿童急性腹泻有强证据, 同种的另一株可能完全无效。这是乳酸菌 概念被滥用的根源: 商家只说含益生菌, 不告诉是哪一株, 通常就是没临床数据的便宜株。
③ 对宿主健康产生有益作用: 需要该菌株加上具体适应症的人体 RCT 证据, 不是理论上有益, 也不是某一指标好看, 必须对具体疾病或症状有临床意义上的改善。
④ 活菌: 死菌不算 probiotic, 虽然 postbiotic 概念在兴起。这就是为什么冲热水、加酸饮料、高温烹调之后的发酵食品, probiotic 价值会打折。
所以判断家里这瓶益生菌 是否真有效, 看三件事:
1. 是否标了具体菌株名 (LGG / BB-12 / DSM xxxxx 等)
2. 这一菌株加你的适应症有没有 RCT
3. 标签是货架期末最低 CFU 还是出厂值
机制 · 为什么株才携带信息
为什么种这一层不够用? 因为决定一株菌能不能干活的那些本事, 都写在株这一层的基因里, 同种的两株可以一个有、一个没有。至少四样本事是这么分出来的:
能不能挂住: 菌表面伸出来的一些蛋白像小钩子, 能不能勾在肠壁那层黏液上, 全看它带不带这些钩子。挂不住的菌, 在肠道一路往下推的水流里待不了多久。扛不扛得住胆汁: 胆汁本质上是去污剂, 会把细胞膜上的脂溶开。能先把胆汁盐拆掉的菌活得下来, 不能的在小肠开头就散了。抢不抢得动地盘: 有些菌会往外分泌毒杀邻居的小分子, 有些不会。这决定了它挤不挤得动已经住在那儿的菌。免疫怎么读它: 菌壁外面那层多糖的形状不同, 肠上皮底下的免疫细胞读出来的信号就不同。同种的两株, 一株可能让免疫更沉得住气, 另一株什么反应也不引起。
所以乳酸杆菌有益这句话的信息量等于零: 它说的是姓, 不是人。
这条也解释了两件常见的事。一是为什么临床试验换一株就得从头做一遍——上一株的钩子、胆汁本事、地盘手段, 下一株未必有。二是为什么把一株菌的证据挪到同种的另一株身上 (货架上最常见的偷换) 不成立: 你买的是那串代号, 不是那个属名。
顺着往下推还有一个实用推论: 一个连菌株代号都不肯印的产品, 不是印不下, 是印出来就得接受这一株有没有做过试验的追问。写不出代号, 本身就是答案。
Star strains cheat sheet
A working list of RCT-supported strains + indications — not exhaustive but it covers 90% of real clinical use.Lactobacillus genus:
L. rhamnosus GG (LGG): prevention of eczema in high-allergy-risk infants (*Kalliomäki 2001* *Lancet*). ⚠️ The pediatric acute-diarrhea line no longer stands: pooling 6 trials and 3,058 participants, Cochrane 2020 found a mean difference of only 8.64 hours shorter — with a range running from 29 hours shorter to 12 hours longer, certainty rated very low. An interval that crosses zero has not demonstrated an effect. AGA 2020 accordingly suggests against probiotics in children with acute infectious gastroenteritisL. rhamnosus GR-1 + L. reuteri RC-14: adjunct for recurrent UTI / vaginosis in women, moderate evidenceL. reuteri DSM 17938: infant colic, some positive RCTsL. casei Shirota (Yakult): general gut function — marketing far outruns clinical evidence
Bifidobacterium genus:
B. lactis BB-12 / DN-173 010: general gut motility, partial symptom improvement in IBSB. infantis 35624 (Align): the single most-named strain in IBS (Ford 2018's meta-analysis, and the same year's ACG IBS monograph, both reached positive conclusions). But the AGA 2020 guideline makes no recommendation on IBS — it says to use probiotics only within a clinical trial. The two societies do not literally agree, so don't write this up as 'guideline-recommended'
Saccharomyces (yeast, not bacterium):
S. boulardii CNCM I-745: moderate-certainty evidence for preventing pediatric antibiotic-associated diarrhea (AAD) (Guo 2019 Cochrane, ages 0-18: 8% on probiotics vs 19% on control, RR 0.45, roughly one case avoided per 9 children treated). The adult case rests on something else: AGA 2020's conditional recommendation for preventing antibiotic-associated C. difficile infection. Traveler's diarrhea has no citation on this site — don't count it as strong evidenceCrucially it's a yeast — antibiotics don't kill it, so it can be taken concurrently with antibiotics
Multi-strain combinations:
VSL#3 (now renamed Visbiome / Vivomixx): 8-strain combo used for chronic pouchitis and some UC casesPediatric multi-strain combinations (various brands): mixed data
Categories without meaningful evidence:
Most supermarket 'digestive health' blends, labeled only as a *Lactobacillus / Bifidobacterium* blend with no specific strain identityThe 'active probiotics in yogurt' marketing line: most yogurts use *L. bulgaricus* + *S. thermophilus*, which barely survive to the colon — they help lactose tolerance but aren't true probioticsPrebiotics (fiber) feeding the bacteria you already have are often more effective than adding new ones
Before buying, ask three things: which strain (only consider if a strain ID is written); is there a human RCT for this strain + your indication (5 minutes on PubMed); is the labeled CFU end-of-shelf-life or manufacture-date?
kalliomaki-2001-lancet
Chapter 2
Acid massacre · 0.01-1% survive
Acid massacre · 0.01-1% survive
'Swallowing 10 billion live bacteria' and '10 billion reaching the colon' are two completely different orders of magnitude.
Stomach acid at pH 1.5-2.0 is lethal for most lactic-acid and bifido strains:
Typical *Lactobacillus* + *Bifidobacterium* strain: 0.01-1% gastric survival*S. boulardii* (yeast): much more acid-resistant, ~10-30% gastric survivalSpore-formers (*Bacillus coagulans* / *B. subtilis*): nearly 100% gastric survival, but clinical evidence is limited
Protection strategies:
Enteric coating: doesn't dissolve in acid, releases in the small intestine — effective delivered CFU rises 10-100×Take with meals: food buffers acid pH, but also dilutesHeat-killed / postbiotic preparations: some studies show dead cells still work, because cell-wall components (LPS, peptidoglycan) modulate immunity — but the concept is still evolving
Colonization is a separate concept — most probiotics do not establish permanent colonies in your gut:
Zmora 2018 *Cell*: an 11-strain probiotic given after antibiotics — most strains had vanished 3-4 weeks after stopping, and mucosal colonization was strongly person-specificSuez 2018 *Cell* (the sister paper, same issue): in some individuals probiotics actually *delayed* the natural recovery of the gut microbiomeReality: probiotics are *transient passengers* — they pass through, leave short-term signals (immune modulation, SCFAs, interactions with resident microbes), and then get washed out
Three clinical implications:
1. Probiotics generally need continuous use to maintain an effect — it isn't 'set the gut once and benefit forever'.
2. Individual variation is huge — some people's gut environment lets specific probiotics temporarily settle; others reject them entirely.
3. Fecal microbiota transplant (FMT) is a categorically different intervention, not a bigger dose of the same one: it delivers the full community + metabolites + the 'home' (mucin / sIgA), which is why it can colonize where a single strain cannot.
So claims like 'yogurt cures everything' or 'one probiotic capsule rewrites your microbiome' miss the real position of probiotics as 'transient + short-term modulators'.
Stomach acid at pH 1.5-2.0 is lethal for most lactic-acid and bifido strains:
Typical *Lactobacillus* + *Bifidobacterium* strain: 0.01-1% gastric survival*S. boulardii* (yeast): much more acid-resistant, ~10-30% gastric survivalSpore-formers (*Bacillus coagulans* / *B. subtilis*): nearly 100% gastric survival, but clinical evidence is limited
Protection strategies:
Enteric coating: doesn't dissolve in acid, releases in the small intestine — effective delivered CFU rises 10-100×Take with meals: food buffers acid pH, but also dilutesHeat-killed / postbiotic preparations: some studies show dead cells still work, because cell-wall components (LPS, peptidoglycan) modulate immunity — but the concept is still evolving
Colonization is a separate concept — most probiotics do not establish permanent colonies in your gut:
Zmora 2018 *Cell*: an 11-strain probiotic given after antibiotics — most strains had vanished 3-4 weeks after stopping, and mucosal colonization was strongly person-specificSuez 2018 *Cell* (the sister paper, same issue): in some individuals probiotics actually *delayed* the natural recovery of the gut microbiomeReality: probiotics are *transient passengers* — they pass through, leave short-term signals (immune modulation, SCFAs, interactions with resident microbes), and then get washed out
Three clinical implications:
1. Probiotics generally need continuous use to maintain an effect — it isn't 'set the gut once and benefit forever'.
2. Individual variation is huge — some people's gut environment lets specific probiotics temporarily settle; others reject them entirely.
3. Fecal microbiota transplant (FMT) is a categorically different intervention, not a bigger dose of the same one: it delivers the full community + metabolites + the 'home' (mucin / sIgA), which is why it can colonize where a single strain cannot.
So claims like 'yogurt cures everything' or 'one probiotic capsule rewrites your microbiome' miss the real position of probiotics as 'transient + short-term modulators'.
机制 · 一个过路菌凭什么管用
先看抗生素把肠道弄成了什么样, 那句风险降一半 (儿童抗生素相关腹泻, Guo 2019 Cochrane) 才有落脚点。抗生素不认敌我。它冲着某个感染去, 顺手把你结肠里的常驻菌也打掉一大片。接着两件事同时发生:
位置空了: 常驻菌平时把墙面上的黏附点和肠腔里的糖全占着, 那些平时挤不进来的机会菌 (艰难梭菌是最出名的一个) 一直在门外排队。常驻菌被打空, 队就放行了。饭没人做了: 会发酵纤维的菌少了, 结肠壁细胞平时最爱吃的那种短链脂肪酸 (丁酸) 就断供。肠壁自己饿着, 该被吸走的水留在肠腔里, 大便就稀。
现在回头看过路菌。它安不了家, 但只要它人在场, 三件事就成立:
占位: 它也要黏附点、也要糖。它把这些抢在手里的那几十个小时, 机会菌就抢不到。这是替补队员站在空位上, 不是新住户搬进来。就地产酸: 它发酵糖, 当场吐出酸, 把那一小片肠腔的酸碱度往下压。不少机会菌在偏酸的环境里长得费劲, 于是被压住。让免疫看见: 它的菌壁碎片会被肠上皮底下的免疫细胞读到。免疫读到外面还有正常菌, 黏液和抗菌肽的产线就不停工——而那层黏液正是屏障的第一道。
三件事有一个共同点: 全都只在它在场的时候成立。这一条几乎把后面所有的实操都解释了——为什么要和抗生素同期吃而不是等疗程结束再补、为什么要连着吃、为什么停了效果就走、为什么调好一次终身受益根本不可能。它不是搬进来改造房子的人, 它是你雇的临时工, 工钱停了人就走。
还有一个特例值得单独记: 布拉迪酵母是酵母, 不是细菌, 抗生素的枪口对不着它。别的菌得等抗生素代谢干净才有活路, 它可以在抗生素还在你体内的时候就站上那些空位。这就是它在抗生素相关腹泻这件事上证据最硬的机制原因, 也是为什么它可以和抗生素同时服, 不必错开时间。
反过来读这三件事, 还能得到一条判断工具: 凡是宣称在菌群完好的健康人身上产生明显效果的益生菌卖点, 先验都很低——位置本来就满着, 前两件事无从谈起, 只剩免疫那一条, 而那一条的效应量本来就小。
过胃这一关 · 谁活得下来
能不能干活的前提是能不能到。这一关的数字很不客气。吃下 100 亿活菌 和100 亿菌到达结肠 是两个数量级完全不同的事。
胃酸 pH 1.5-2.0 对大多数乳酸菌和双歧杆菌都是致命的:
典型 Lactobacillus + Bifidobacterium 株: 通过胃后的存活率 0.01-1%S. boulardii (酵母): 抗酸能力强得多, 通过胃后约 10-30% 存活孢子形成菌 (Bacillus coagulans / B. subtilis): 通过胃几乎 100%, 但临床证据有限
保护策略:
肠溶包衣 (enteric coating): 在胃酸里不溶解, 到达小肠后释放, 有效到达 CFU 提升 10-100 倍餐时服用: 食物缓冲胃酸 pH, 但同时稀释死菌制剂 (postbiotic / heat-killed): 部分研究显示死菌也有效, 因为菌壁成分 (LPS、肽聚糖) 本身能调节免疫, 但概念仍在演变
⚠️ 这些百分比要当量级读, 不要当精确值。 存活率随菌株、剂型和测量方法差出好几个数量级: 综述里对专门筛选过耐酸性的菌株给出的估计可以高到 20-40%, 而货架上没做过这层筛选的普通株就落在上面那个很低的区间。所以别把某个具体数字背下来, 记住的应该是那条规律: 耐酸性是菌株层面的性状, 不是整个益生菌类别的性状。
bezkorovainy-2001-ajcn-survival
定植 · 为什么它住不下来
定植 (colonization) 是另一个概念——多数 probiotic 不能在你的肠道里建立永久菌落:Zmora 2018 *Cell*: 抗生素后服 11 株 probiotic, 多数在停用 3-4 周后消失, 而且能不能挂在肠黏膜上因人而异Suez 2018 *Cell* (同一期的姐妹研究): probiotic 在某些个体身上反而延迟了肠道菌的自然恢复真相: probiotic 是过路菌, 它们经过, 留下一点短期信号 (帮着调一调免疫、产一些有益的短链脂肪酸 short-chain fatty acids: Small molecules (acetate/propionate/butyrate) gut bacteria make from fiber — they feed the gut lining and calm inflammation.、和你原有的菌互动几句), 然后就被冲走
这有三个临床含义:
1. probiotic 通常需要持续服用才能维持效果, 不是调好一次终身受益
2. 个体差异大: 有些人的肠道环境让特定 probiotic 暂时定植, 有些则完全不接受
3. 粪便菌移植 (FMT) 不是加大剂量的益生菌, 而是另一类干预: 它传递完整菌群、代谢物, 加上菌的家 (mucin / sIgA), 所以它能定植, 而单株菌不能
所以酸奶治百病 或一颗益生菌胶囊改写微生物组 这类宣传, 都偏离了 probiotic 过路菌 + 暂时调节 的真实定位。
为什么住不下来, 机制其实很朴素: 结肠不是一间空房, 是一间满员的房。一株菌要待住得同时满足两件事——找得到墙面上没被占的黏附点, 以及找得到没被别人吃掉的那口饭。常驻菌早把这两样占满了, 而且还往外分泌压制邻居的小分子。新来的一株没有空位可占, 就只能悬在肠腔的水流里; 而肠内容物一直在往下走, 悬着的东西自然被冲出去。
所以停用之后迅速查不到, 不是被杀死, 是被冲走。这两个词差别很大: 前者暗示你可以加大剂量硬扛过去, 后者告诉你剂量再大也只是把被冲走的时间往后推一点。
顺着这条链还能推出两件事:
为什么益生元 (说白了就是纤维) 常常比补菌更划算: 纤维喂的是已经占好位、已经住下来的常驻菌, 它压根不需要过定植这一关, 也不怕胃酸。你不是往满员的房间里塞人, 是给已经住在里面的人送饭。为什么整套菌群一起移植是另一个量级的事: 那不是往满员的房间里再塞一个人, 而是换掉整屋住户, 连同他们之间的分工一起搬进来。后面那一格讲的就是它。
Fermented food vs supplement
The Sonnenburg lab's 2021 *Cell* study (covered in the digestive story) is a high-quality RCT: 36 randomized, 18 per arm, 10 weeks.Group A: high-fiber dietGroup B: high-fermented-food diet (yogurt, kefir, kimchi, sourdough, kombucha, vinegared vegetables)
Results:
Group B (fermented foods): microbiome diversity ↑; of the 93 cytokines, chemokines, and other inflammatory serum proteins measured, 19 decreased (the publicly reported names are interleukin-6: A pro-inflammatory signal molecule (cytokine) released by immune cells during inflammation., IL-10, IL-12b) — 19 out of 93, not 'across the board'Group A (high fiber): limited improvement; some subjects' microbiomes couldn't ferment that much fiber (needed adaptation + slow ramp-up)
This result shocked the microbiome field: in theory fiber should win (directly feeds bacteria to produce SCFAs), but fermented foods won.
Mechanism hypothesis: fermented foods simultaneously deliver multiple live cultures, their metabolites (short-chain fatty acids, amino acids, vitamin K2, polyphenol derivatives), and cell-wall components (the postbiotic effect). This is the 'whole-food matrix' effect — not a single strain, but bacteria + metabolites + food matrix together; probiotic capsules deliver a single high-purity strain and lose this matrix.
Practical recommendations:
Rotate fermented foods as the first move: plain unsweetened yogurt, kefir, kimchi, sauerkraut, natto, miso, kombucha, vinegared vegetables1-2 different types daily works better than 'one cup of the same yogurt every day'Pair with fiber to feed your existing bacteria: oats, legumes, whole grains, vegetables, fruitUse supplements only for specific indications — AAD, IBS, recurrent UTI, acute pediatric diarrhea, and other RCT-supported scenariosDon't take probiotic capsules long-term for vague 'gut health' — fermented food + fiber + dietary diversity is stronger for almost everyone
This is why the section is titled 'Gastric massacre': the vast majority of probiotics die before reaching the battlefield. What actually tunes the microbial ecosystem is repeatedly giving the bacteria a good working environment (fiber, diversity, fewer antibiotics) — not dropping a single dose of hundreds of millions of soldiers in.
Chapter 3
Evidence tiers · indication list
Evidence tiers · indication list
Probiotics aren't 'good for everything' — layering by RCT evidence strength makes the picture much clearer.
A-tier (strong RCT + meta-analysis):
Antibiotic-associated diarrhea (AAD) prevention in children: *S. boulardii* or LGG taken with the antibiotic — 8% vs 19%, RR 0.45, about one case avoided per 9 children treated, moderate certainty (Guo 2019 Cochrane). This is a pediatric result; don't quietly generalize it to adultsPreventing **antibiotic-associated *C. difficile* infection** in adults and children on antibiotics: AGA 2020 conditionally suggests specific probiotics (low certainty). Recurrent, established *C. difficile* infection is a different question — there FMT is the gold standard (80-90% cure) and AGA makes no recommendation on probiotics outside a trialNecrotizing enterocolitis (NEC) prevention in preterm infants: AGA 2020 suggests specific *Lactobacillus* + *Bifidobacterium* combinations. ⚠️ This benefit comes with a real, documented harm — see the safety page: in September 2023 the FDA warned that preterm infants given probiotics risk invasive, potentially fatal disease, after an infant under 1000 g died of *Bifidobacterium longum* sepsis genomically matched to the product administered. Both halves are true, and this is a decision for the neonatal team, not a shelf purchase
B-tier (RCT evidence but mixed or small effects):
IBS: specific strains (*B. infantis* 35624, multi-strain combos) give modest improvement in meta-analysis (Ford 2018, *Aliment Pharmacol Ther*) and in the same year's ACG monograph — but AGA 2020 makes no recommendation for IBS and says to use probiotics only inside a clinical trial. Read that disagreement as the honest state of the evidencePediatric acute infectious diarrhea: demoted out of the A tier. Cochrane 2020 (Collinson) pooled 6 trials / 3,058 participants and found the duration difference was 8.64 hours shorter with a range from 29 hours shorter to 12 hours longer — very low certainty. AGA 2020 suggests against probiotics in children with acute infectious gastroenteritisInfant colic: *L. reuteri* DSM 17938 partially positiveAllergy / eczema *primary* prevention: LGG during pregnancy / infancy in high-risk families cuts incidence ~25%Adjunctive bacterial vaginosis: paired with antibiotics, reduces recurrence
C-tier (mixed, weak real-world impact):
'Immunity' / common-cold prevention: weakly positive small RCTs, effect size smallAllergic rhinitis: weak evidenceTreating (not preventing) atopic dermatitis: limited effectDepression / anxiety ('psychobiotics'): early evidence is interesting but RCTs are few and effects smallAthletic performance: only 1-2 small RCTs
No meaningful evidence but widely marketed: weight loss (no strain has been shown to lower body weight); anti-aging / longevity (no human RCT); autism spectrum (animal studies yes, human RCTs null); beauty / skin glow (marketing); diabetes prevention / glucose control (small signal, weak).
Important warnings:
Critically ill / immunosuppressed / central venous line patients: probiotics can cause bacteremia (rare but real) — use cautiously in ICUSevere pancreatitis: the 2008 PROPATRIA *Lancet* trial showed a multi-strain probiotic doubled mortality — severe illness is not a 'just add bacteria' situationPreterm infants in hospital: FDA safety warning, September 2023 — preterm infants given probiotics are at risk of invasive, potentially fatal disease caused by the organisms in the product. One infant under 1000 g birthweight died of *B. longum* sepsis genomically matched to the probiotic administered. No probiotic is FDA-approved for use in infants of any agePregnancy / infants: most evidence comes from LGG / BB-12 with long safety records; don't substitute random other strains
To decide whether a probiotic is worth buying, ask three things:
1. Is my indication on the A-B list?
2. Does it contain a specific strain with an RCT — not a generic 'broad-spectrum' blend?
3. Could I substitute fermented foods + fiber?
If none of the three apply, the money is better spent at the produce market.
A-tier (strong RCT + meta-analysis):
Antibiotic-associated diarrhea (AAD) prevention in children: *S. boulardii* or LGG taken with the antibiotic — 8% vs 19%, RR 0.45, about one case avoided per 9 children treated, moderate certainty (Guo 2019 Cochrane). This is a pediatric result; don't quietly generalize it to adultsPreventing **antibiotic-associated *C. difficile* infection** in adults and children on antibiotics: AGA 2020 conditionally suggests specific probiotics (low certainty). Recurrent, established *C. difficile* infection is a different question — there FMT is the gold standard (80-90% cure) and AGA makes no recommendation on probiotics outside a trialNecrotizing enterocolitis (NEC) prevention in preterm infants: AGA 2020 suggests specific *Lactobacillus* + *Bifidobacterium* combinations. ⚠️ This benefit comes with a real, documented harm — see the safety page: in September 2023 the FDA warned that preterm infants given probiotics risk invasive, potentially fatal disease, after an infant under 1000 g died of *Bifidobacterium longum* sepsis genomically matched to the product administered. Both halves are true, and this is a decision for the neonatal team, not a shelf purchase
B-tier (RCT evidence but mixed or small effects):
IBS: specific strains (*B. infantis* 35624, multi-strain combos) give modest improvement in meta-analysis (Ford 2018, *Aliment Pharmacol Ther*) and in the same year's ACG monograph — but AGA 2020 makes no recommendation for IBS and says to use probiotics only inside a clinical trial. Read that disagreement as the honest state of the evidencePediatric acute infectious diarrhea: demoted out of the A tier. Cochrane 2020 (Collinson) pooled 6 trials / 3,058 participants and found the duration difference was 8.64 hours shorter with a range from 29 hours shorter to 12 hours longer — very low certainty. AGA 2020 suggests against probiotics in children with acute infectious gastroenteritisInfant colic: *L. reuteri* DSM 17938 partially positiveAllergy / eczema *primary* prevention: LGG during pregnancy / infancy in high-risk families cuts incidence ~25%Adjunctive bacterial vaginosis: paired with antibiotics, reduces recurrence
C-tier (mixed, weak real-world impact):
'Immunity' / common-cold prevention: weakly positive small RCTs, effect size smallAllergic rhinitis: weak evidenceTreating (not preventing) atopic dermatitis: limited effectDepression / anxiety ('psychobiotics'): early evidence is interesting but RCTs are few and effects smallAthletic performance: only 1-2 small RCTs
No meaningful evidence but widely marketed: weight loss (no strain has been shown to lower body weight); anti-aging / longevity (no human RCT); autism spectrum (animal studies yes, human RCTs null); beauty / skin glow (marketing); diabetes prevention / glucose control (small signal, weak).
Important warnings:
Critically ill / immunosuppressed / central venous line patients: probiotics can cause bacteremia (rare but real) — use cautiously in ICUSevere pancreatitis: the 2008 PROPATRIA *Lancet* trial showed a multi-strain probiotic doubled mortality — severe illness is not a 'just add bacteria' situationPreterm infants in hospital: FDA safety warning, September 2023 — preterm infants given probiotics are at risk of invasive, potentially fatal disease caused by the organisms in the product. One infant under 1000 g birthweight died of *B. longum* sepsis genomically matched to the probiotic administered. No probiotic is FDA-approved for use in infants of any agePregnancy / infants: most evidence comes from LGG / BB-12 with long safety records; don't substitute random other strains
To decide whether a probiotic is worth buying, ask three things:
1. Is my indication on the A-B list?
2. Does it contain a specific strain with an RCT — not a generic 'broad-spectrum' blend?
3. Could I substitute fermented foods + fiber?
If none of the three apply, the money is better spent at the produce market.
分层清单 · A / B / C 级
按证据强度排一遍。顺序本身就是信息: 越往下, 你越该怀疑印在瓶子正面的那句话。A 级 (强 RCT + meta-analysis):
儿童抗生素相关腹泻 (AAD) 预防: S. boulardii 或 LGG 与抗生素同服, 益生菌组 8% vs 对照 19% (RR 0.45, 大约每治 9 个孩子少 1 例, 中等确定性; Guo 2019 Cochrane)。这是儿童数据, 别不声不响地挪到成人身上成人和儿童在吃抗生素期间预防艰难梭菌感染: AGA 2020 弱推荐特定菌株 (低确定性)。注意这和已经发作的复发性艰难梭菌感染是两回事——后者的金标准是 FMT (80-90% 治愈), AGA 对那一档的益生菌不给推荐, 只说在临床试验里用早产儿坏死性小肠结肠炎 (NEC) 预防: AGA 2020 弱推荐特定的乳杆菌加双歧杆菌组合。⚠️ 这一条的收益和一条真实伤害捆在一起: 2023 年 9 月 FDA 警告, 给早产儿用益生菌有发生侵袭性、可能致命感染的风险——一名出生体重不足 1000 g 的早产儿死于双歧杆菌 (B. longum) 败血症, 基因测序显示致病菌与所用产品里的菌完全对得上。两半都是真的, 所以这是新生儿科团队的决定, 不是货架上的选择 (细节见安全那一页)
B 级 (有 RCT 证据, 但混杂或效应小):
IBS (肠易激): 特定菌株 (B. infantis 35624、多菌组合) 小幅改善——Ford 2018 的 meta 和同年美国胃肠病学院 ACG 的专论都是正性结论, 但美国胃肠协会 AGA 2020 对 IBS 不给推荐, 只说在临床试验里用。两家不一致这件事本身, 就是当前证据的真实状态儿童急性感染性腹泻: 已从 A 级降下来。 Cochrane 2020 (Collinson) 汇总 6 项试验 3058 人, 病程只缩短 8.6 小时, 而误差范围从缩短 29 小时跨到延长 12 小时, 确定性极低; AGA 2020 对这一条明确不建议婴儿肠绞痛: L. reuteri DSM 17938 部分阳性过敏、湿疹一级预防: 孕期、婴儿期 LGG 在高风险家庭里降发生率约 25%细菌性阴道病辅助: 与抗生素配合, 复发风险下降
C 级 (混杂证据, 实际意义弱):
免疫力、普通感冒预防: 部分 RCT 弱正性, 效应小过敏性鼻炎: 弱证据特应性皮炎治疗 (已确诊): vs 一级预防, 治疗效果差抑郁、焦虑 (psychobiotics): 早期证据有趣, 但 RCT 数量少 + 效应小运动表现: 仅 1-2 个小 RCT
没有有意义证据但常被营销宣称的几类: 减肥 (没有任何菌株被证明降体重); 抗衰老、长寿 (没有人体 RCT); 自闭症谱系 (有动物研究, 人体 RCT 阴性); 美容、皮肤光泽 (营销话术); 糖尿病预防、血糖控制 (个别小研究信号弱)。
判断这个 probiotic 值不值得买, 问自己三件事:
1. 我的适应症是否在 A-B 级清单里?
2. 它含的菌株是不是有 RCT 的具体株, 而不是广谱?
3. 我能不能用发酵食品 + 纤维替代?
三个都不满足, 那这笔钱花在菜场更好。
fda-2023-probiotics-preterm-warning
机制 · 强证据为什么只落在那几处
把 A 级那几条排在一起看, 它们共享同一个形状: 肠道菌群此刻是空的, 或者还没建起来。正在吃抗生素的人: 常驻菌被打掉一片, 墙面和口粮空出来, 机会菌在门外排队。急性病毒性腹泻的孩子: 肠内容物一天冲刷好几遍, 把常驻菌一起冲淡, 同时肠壁本身还在修。早产儿: 菌群还在从零往上建, 谁先到谁占位。
只有在这几种情况下, 一个过路菌带来的占位 + 产酸 + 让免疫看见才有杠杆, 因为有位置可占。反过来, 菌群完好的健康成年人身上位置本来就满着, 再塞一株进去, 它连站的地方都找不到, 几十个小时后就被冲走了。
这条推理是全篇最有用的一件工具, 因为它让你不必背下整张表也能判断没见过的新宣称:
某个卖点声称在普通健康人身上产生明显效果 → 先验很低, 因为它要求过路菌在没有空位的环境里做功。某个卖点声称改变的是长期指标 (体重、寿命、皮肤状态) → 先验更低, 因为过路菌的作用随停用消失, 而长期指标需要长期在场的东西去推动。某个卖点落在菌群刚被扰动的窗口里 → 值得认真看它到底用了哪一株、在哪个人群做的试验。
同一件事的另一面: 这也解释了为什么益生菌的效果在人和人之间差别那么大。你的肠道当下是空是满、常驻菌是哪一副组合, 决定了同一粒胶囊在你身上有没有落脚点——这不是体质这种模糊说法, 而是一个很具体的有没有空位的问题。
安全 · 什么时候反而不该吃
几条重要警告:危重患者、免疫抑制、中心静脉导管者: probiotic 可能导致菌血症 (罕见但真实), ICU 谨慎使用重症胰腺炎: PROPATRIA 试验 2008 *Lancet* 显示多菌组合死亡率升高 2 倍, 重病不是多补点细菌 的场合住院的早产儿: 2023 年 9 月 FDA 发出警告, 给早产儿用益生菌有发生侵袭性、可能致命感染的风险。一名出生体重不足 1000 g 的早产儿在院内用过一款益生菌后死于双歧杆菌 (B. longum) 败血症, 基因测序显示致病菌与产品里的菌是同一株。FDA 同时提醒: 美国没有任何一款益生菌被批准用于婴儿怀孕、婴儿: 大多数证据来自 LGG / BB-12 等长期使用安全的株, 不要随便买其它
⚠️ 早产儿这一条要和前面那张分层表一起读, 不要只记一半。 同一群早产儿, 益生菌确实能降低坏死性小肠结肠炎的风险 (AGA 2020 弱推荐), 同时也确实有孩子死于产品里的那株菌。这不是两个互相矛盾的说法, 这就是一件收益和伤害同时存在的事——正因为如此, 它必须由新生儿科团队逐个孩子权衡, 而不是家长在货架前决定。
这几条不是保险起见的套话, 它们落在一条很具体的链上: 益生菌是活的, 而肠壁只是一层细胞。
健康人身上, 这层细胞加上覆在它表面的黏液, 把菌牢牢关在肠腔那一侧; 危重、免疫抑制、肠壁本身受损, 或者身上插着直通血管的导管时, 这道关不严了, 本来只该待在肠腔里的活菌就可能越过去, 进入血流。这就是菌血症。
所以多补点好菌这个直觉在重病场景里是彻底反过来的: 你补的不是一种营养素, 是活的生物; 营养素进错地方最多是浪费, 活菌进错地方就是感染。这也是为什么这一条永远该由医生判断, 而不是由你在货架前判断。
besselink-2008-propatria-lancetfda-2023-probiotics-preterm-warning
Label traps · billion bacteria fog
Common label traps.'10 billion live bacteria': is that the manufacture-date number or the end-of-shelf-life number? Most cheap products overstate at manufacture; 6 months later only 1-10% remains. Good labels write 'At expiration: X CFU' or include refrigeration instructions.
'16-strain blend': sounds more comprehensive, but strains often compete / inhibit each other, and per-strain CFU gets diluted; clinical RCTs are almost all single-strain + single-indication, not 'the full bouquet'. VSL#3 / Visbiome is one of the few multi-strain combos with RCT evidence.
'Now with prebiotic — upgraded version': prebiotics (fiber / FOS / inulin) work on their own, but there's almost never data on whether they synergize with the specific probiotic strain you're buying. Eating more fiber on its own is much cheaper.
'Clinically proven' / 'Doctor recommended': with no FDA or major medical-society evaluation behind it, this is marketing rhetoric. The real consensus that exists is the AGA 2020 guideline, and its three verdicts have to be kept apart:
Conditionally suggests using: pouchitis; **prevention of *C. difficile* infection in adults and children taking antibiotics**; prevention of NEC in preterm low-birth-weight infantsSuggests against: children with acute infectious gastroenteritis (moderate certainty)No recommendation — use only within a clinical trial: Crohn's disease, ulcerative colitis, IBS, and established *C. difficile* infection
⚠️ The one most often reversed is *C. difficile*: preventing it while on antibiotics is a conditional yes; treating established infection is where AGA declines to recommend. As for generic 'gut health', the guideline has no such row at all — never evaluated is not the same as recommended.
'Live bacteria / probiotic / postbiotic' concept upgrades: heat-killed cells or bacterial metabolites — theoretically interesting, but RCTs are scarce; don't pay a premium for a concept upgrade.
Cold-storage vs shelf-stable: cold-storage products typically have higher activity but are harder to travel with; shelf-stable products use spore-formers (*Bacillus*) or lyophilization — convenient, but some strains lose potency relative to their refrigerated equivalents. Pick the form you'll actually keep taking; that matters more than 'theoretically better' but inconvenient.
Operational bottom line:
Have an A-B indication: buy the RCT-validated strain for that indication (LGG, *S. boulardii*, 35624, etc.)'Tune my gut': fermented foods + high fiber + dietary diversity > probiotic supplementSeverely ill / immunosuppressed: discuss with a doctorHealthy person wanting 'insurance' daily supplementation: don't bother — spend the money on vegetables and fruit
Chapter 4
Fermented foods · daily probiotics
Fermented foods · daily probiotics
Fermented foods are an 8000-year byproduct of food preservation and the real daily source of probiotics — better evidence and cheaper than capsules.
Main types (by region and culture):
Yogurt: standard *L. bulgaricus* + *S. thermophilus* cultures; real yogurt's ingredient list is just 'milk + active cultures' — no sugar, no flavoring, no thickenersKefir: milk- or water-based, 10-30 bacteria + yeast in mixed fermentation; far more diverse than yogurtKimchi (Korean): vegetables + lactic-acid-bacteria fermentation, plus chili and anti-inflammatory polyphenolsSauerkraut (German): cabbage + salt, spontaneous fermentationNatto (Japanese): *Bacillus subtilis* var. *natto* — the only food source of K2 (MK-7)Miso / soy sauce: *Aspergillus oryzae* koji + later bacterial activity; salt + partial pasteurization leave few live cellsKombucha: tea + SCOBY (symbiotic culture of bacteria + yeast), contains acetic-acid bacteria + yeastSourdough: wild yeast + lactic-acid bacteria; most cells die during baking, but phytate is reduced and glycemic response is gentler
Real fermentation vs fake fermentation:
Real: cultures inoculated naturally or deliberately, refrigerated, label reads 'live cultures'Fake (commercial short-ferment + pasteurized): shelf-stable (no refrigeration), ingredient list reads 'vinegar' rather than 'culture', almost no live cells
Most supermarket pickled cucumbers, vinegar-pickled vegetables, and heat-treated German sauerkraut aren't real fermentation; refrigerated brands like Bubbies, Wildbrine, and homemade kimchi are.
Health evidence for fermented foods:
Sonnenburg 2021 *Cell* (previous page): 10 weeks → 19 inflammation markers down, diversity upKorean cohorts (Park 2017 and others): high kimchi intake correlates with lower BMI / metabolic syndrome (with confounders)Yogurt + CV: multiple meta-analyses link yogurt with lower diabetes / CV risk
Practical:
Rotate 1-2 different fermented foods daily — stronger than 'same brand every day'Breakfast yogurt or kefir 200 g + small kimchi or sauerkraut 50-100 g with meals is a good comboLactose intolerant: try plant-based yogurts, coconut kefir, vinegared vegetables, kombuchaSalt watch: Korean kimchi and German sauerkraut are high-salt — hypertension patients bewareChildren / elderly / immunosuppressed: prioritize commercial pasteurized + culture-added products, avoid home spontaneous fermentation (contamination risk)
Main types (by region and culture):
Yogurt: standard *L. bulgaricus* + *S. thermophilus* cultures; real yogurt's ingredient list is just 'milk + active cultures' — no sugar, no flavoring, no thickenersKefir: milk- or water-based, 10-30 bacteria + yeast in mixed fermentation; far more diverse than yogurtKimchi (Korean): vegetables + lactic-acid-bacteria fermentation, plus chili and anti-inflammatory polyphenolsSauerkraut (German): cabbage + salt, spontaneous fermentationNatto (Japanese): *Bacillus subtilis* var. *natto* — the only food source of K2 (MK-7)Miso / soy sauce: *Aspergillus oryzae* koji + later bacterial activity; salt + partial pasteurization leave few live cellsKombucha: tea + SCOBY (symbiotic culture of bacteria + yeast), contains acetic-acid bacteria + yeastSourdough: wild yeast + lactic-acid bacteria; most cells die during baking, but phytate is reduced and glycemic response is gentler
Real fermentation vs fake fermentation:
Real: cultures inoculated naturally or deliberately, refrigerated, label reads 'live cultures'Fake (commercial short-ferment + pasteurized): shelf-stable (no refrigeration), ingredient list reads 'vinegar' rather than 'culture', almost no live cells
Most supermarket pickled cucumbers, vinegar-pickled vegetables, and heat-treated German sauerkraut aren't real fermentation; refrigerated brands like Bubbies, Wildbrine, and homemade kimchi are.
Health evidence for fermented foods:
Sonnenburg 2021 *Cell* (previous page): 10 weeks → 19 inflammation markers down, diversity upKorean cohorts (Park 2017 and others): high kimchi intake correlates with lower BMI / metabolic syndrome (with confounders)Yogurt + CV: multiple meta-analyses link yogurt with lower diabetes / CV risk
Practical:
Rotate 1-2 different fermented foods daily — stronger than 'same brand every day'Breakfast yogurt or kefir 200 g + small kimchi or sauerkraut 50-100 g with meals is a good comboLactose intolerant: try plant-based yogurts, coconut kefir, vinegared vegetables, kombuchaSalt watch: Korean kimchi and German sauerkraut are high-salt — hypertension patients bewareChildren / elderly / immunosuppressed: prioritize commercial pasteurized + culture-added products, avoid home spontaneous fermentation (contamination risk)
机制 · 发酵在罐子里替你做了什么
发酵这件事的原始动机不是健康, 是保存。而保存的原理本身就是一条干净的机制链。第一步: 菌把糖吃掉, 吐出酸。 乳酸菌把食物里的糖发酵成乳酸, 罐子里的酸碱度一路往下走。绝大多数会让食物腐败的杂菌在这个酸度里长不起来, 于是食物存住了。你尝到的那股酸, 就是保存机制本身的味道——酸不是发酵的副产品, 酸就是发酵在干的活。
第二步: 酸和酶把大分子拆小。 菌在这段时间里顺带替你做了一轮预消化: 一部分乳糖被拆掉 (这是很多乳糖不耐的人能吃酸奶却喝不了牛奶的原因); 谷物和豆子里那种会把铁和锌牢牢抓住不放的植酸被拆掉一部分, 于是这些矿物质更容易被你的小肠拿走; 一部分蛋白被切成小肽和游离氨基酸, 也就更好吸收, 顺带带来鲜味。
第三步: 菌把自己的产物留在食物里。 短链脂肪酸、一些维生素、被菌改过形态的多酚。这些不是活菌, 是活菌干活留下的东西, 通称后生元。它们不怕胃酸, 也不需要定植, 更不需要在你肠子里安家。
三步做完, 一罐发酵食品里同时装着三样东西:
活菌——娇气, 大部分过不了胃那一关代谢物——不娇气, 全都到被改造过的食物基质——不娇气, 全都到
胶囊只装了第一样, 而且恰好是三样里最容易折损的那一样。这就是整体食物矩阵这个说法的具体含义, 也是为什么在同一项试验里, 换着吃发酵食品的那组会赢过只加纤维的那组。
顺带能解释两件常被问到的事:
为什么冲滚水、拌进热汤、做成常温罐头之后要打折? 活菌是靠一整套酶撑着的活体, 高温把这些蛋白折散就折不回来了。但折掉的只是第一样, 后两样还在——所以加热过的发酵食品不是变成了垃圾, 只是从三样变成了两样。为什么味噌、酱油这类经过盐渍和加热的东西活菌很少, 却仍然值得吃? 同一个道理: 你要的那两样一直都在。
常见品类 · 真发酵 vs 假发酵
发酵食品是 8000 年食品保存技术的副产品, 也是真正每日的 probiotic 来源, 比胶囊更有循证, 也更便宜。主要类型 (按地区和菌种):
酸奶 (yogurt): L. bulgaricus + S. thermophilus 标准培养; 真酸奶配料表只有奶 + 活菌培养, 不加糖、不调味、不加增稠剂开菲尔 (kefir): 牛奶或水基, 10-30 种菌 + 酵母混合发酵, 多样性比酸奶高得多泡菜、韩式泡菜 (kimchi): 蔬菜 + 乳酸菌发酵, 含辣椒和抗炎多酚酸菜 (sauerkraut, 德式): 卷心菜 + 盐自发酵纳豆 (Japanese natto): Bacillus subtilis var. natto, 是唯一 K2 (MK-7) 的食物来源味噌 (miso) / 酱油: Aspergillus oryzae 曲菌 + 后期细菌; 经过盐 + 部分巴氏杀菌, 活菌少康普茶 (kombucha): 茶 + SCOBY (symbiotic culture), 含醋酸菌 + 酵母酸面包 (sourdough): 天然酵母 + 乳酸菌; 烘焙后大部分菌死亡, 但抗营养物质 (植酸) 下降, 血糖反应温和
真发酵 vs 假发酵:
真发酵: 用菌种自然或人工接种, 冷藏储存, 配料表会写活性培养 或Live cultures假发酵 (商业短发酵 + 巴氏杀菌): 货架稳定 (不需冷藏), 配料表写 "vinegar" 而非 "culture", 几乎无活菌
大多数超市架上的腌黄瓜、醋渍菜、加热处理过的德式酸菜其实不是真发酵; 冷藏区的 Bubbies、Wildbrine、自制泡菜才是。
证据与实操 · 每天怎么吃
发酵食品的健康证据:Sonnenburg 2021 *Cell* (上一页): 10 周降 19 种炎症标志物, 多样性 ↑韩国队列 (Park 2017 等): 高 kimchi 摄入与 BMI / 代谢综合征 ↓ 相关 (但有混杂)酸奶 + CV: 多个 meta-analysis 显示与糖尿病 / CV 风险下降相关
实操:
每天 1-2 份不同发酵食品, 比同一品牌每天吃强早餐酸奶或开菲尔 200 g + 餐配少量泡菜或酸菜 50-100 g 是好搭配不耐乳糖可以试植物基酸奶、椰子开菲尔、醋渍蔬菜、康普茶盐摄入注意: 韩式泡菜和德式酸菜含盐高, 高血压患者要留意儿童、老人、免疫抑制者优先选商业化 + 巴氏后接种产品, 避免家庭自发酵 (污染风险)
Yogurt buying · 1-line ingredient rule
Real yogurt vs the 'milk beverage' trap — the ingredient list tells you in 1 minute.Real yogurt ingredients: 'raw milk, *Streptococcus thermophilus*, *Lactobacillus bulgaricus*' — that's it, no more than 5 items.
Milk-beverage / flavored-yogurt common ingredients (to avoid):
Raw milk / reconstituted milk / waterWhite sugar / HFCS / sucrose appearing in large quantitiesFlavoring agentsThickeners (pectin / carrageenan / xanthan gum)Food coloringPreservatives (potassium sorbate)
A few common misconceptions:
'Sugar-free' doesn't equal healthy — check grams of carbohydrate. Real yogurt has ~4 g carbs/100 g (lactose); 'sugar-free' flavored yogurts may still contain artificial sweetenersGreek yogurt is strained and concentrated — high protein (10 g/100 g vs 3-4 g in regular), low carb — a good choiceWhole-fat vs non-fat: multiple meta-analyses show whole-fat yogurt associates with *lower* CV risk — don't fall for the 'low-fat' label
For children: under 3, prioritize whole-fat plain yogurt (no sugar) — protein, calcium, and fortified vitamin D for development; sugared 'kids' yogurts' contain sugar comparable to soda — pure marketing.
For lactose intolerance: fermentation partially degrades lactose in yogurt or kefir, and most lactose-intolerant people tolerate 100-200 g; with full intolerance or milk-protein allergy, choose plant-based (soy, coconut, almond) — but plant-based yogurts have lower protein and calcium, so pick fortified versions.
Storage details: refrigerate strictly < 6°C; finish within 3-5 days after opening; whey separation (yellow liquid) is normal — protein-rich, don't pour it off; clumping, off smell, or bulging lid → discard.
'Yogurt cures everything' marketing vs reality:
Gut tuning: real yogurt + dietary diversity has some evidence, don't expect miracles'Boosts immunity': vagueWhitening / weight loss: no evidence
Yogurt's best role: natural, high-protein, moderate-calorie, Ca + D fortified, low-GI breakfast or snack component — treat it as food, not medicine.
Chapter 5
FMT · the gold standard
FMT · the gold standard
Fecal Microbiota Transplantation (FMT) sounds disgusting, but it's one of the rare cases in modern medicine of a 'whole-ecosystem transplant' with an 80-90% cure rate for a single indication.
FDA / NICE-approved indication: recurrent *Clostridioides difficile* infection is the gold standard. After three or more recurrences despite standard antibiotic therapy, FMT achieves an 80-90% cure rate (van Nood 2013 *NEJM*, the classic RCT — stopped early because the effect was so strong). In 2022 the US FDA approved the first stool-derived live biotherapeutic, RBX2660 (Rebyota) — note it is a rectal suspension, not a capsule; SER-109 (Vowst), approved 2023, is the first oral capsule form.
Research-stage indications (B-C tier):
IBD (ulcerative colitis): partial positive RCTs for remission, but require multiple high-frequency sessionsIBS-D: small RCTs show symptom improvementMetabolic syndrome / insulin resistance: Vrieze 2012 *Gastroenterology* — transplanting from lean to obese subjects raised insulin sensitivity at 6 weeks, but the effect was transientAutism (ASD): Kang 2017 *Microbiome*, n=18 — reported symptom improvement, but it was open-label with no control group, which is exactly the design that cannot separate a real effect from expectation and natural fluctuation. The same page warns you not to trust DIY FMT; this study is why the research version isn't settled eitherDepression / anxiety: early stageMultiple sclerosis: early research
Why FMT can do what a probiotic cannot — it is a different kind of intervention, not a larger dose of the same one:
1. Transfers the full microbial community — 1,000+ species including unculturable ones; a probiotic capsule has 1-16 strains
2. Transfers bacterial metabolites — short-chain fatty acids, vitamins, bile-acid metabolism already running
3. Transfers the 'home' — mucin, peptidoglycan, fungal components, phages
4. Transfers a pre-selected community that has already worked in another healthy individual
Delivery methods: colonoscopy / enema (traditional, direct colonization); nasojejunal tube (NJ tube, upper-GI delivery); frozen capsules (oral 'crapsules', now in many hospitals); donor stool banks (OpenBiome in the US; similar in other countries).
Risks: pathogen transmission requires strict donor screening (HIV / HBV / HCV / parasites / multi-drug-resistant organisms). In 2019 two immunocompromised US recipients of stool from the same donor developed ESBL-producing *E. coli* bacteremia and one of the two died (DeFilipp 2019 *NEJM*) — often mis-retold as 'two deaths'. FDA upgraded screening standards in response. Long-term effects remain unknown — does FMT transplant metabolic tendency, behavior, or immunity? Active research.
The current consensus is that FMT is not 'general wellness' — it is a specific medical treatment under regulatory oversight. Don't trust any 'DIY FMT' or 'home stool transplant' clinic.
FDA / NICE-approved indication: recurrent *Clostridioides difficile* infection is the gold standard. After three or more recurrences despite standard antibiotic therapy, FMT achieves an 80-90% cure rate (van Nood 2013 *NEJM*, the classic RCT — stopped early because the effect was so strong). In 2022 the US FDA approved the first stool-derived live biotherapeutic, RBX2660 (Rebyota) — note it is a rectal suspension, not a capsule; SER-109 (Vowst), approved 2023, is the first oral capsule form.
Research-stage indications (B-C tier):
IBD (ulcerative colitis): partial positive RCTs for remission, but require multiple high-frequency sessionsIBS-D: small RCTs show symptom improvementMetabolic syndrome / insulin resistance: Vrieze 2012 *Gastroenterology* — transplanting from lean to obese subjects raised insulin sensitivity at 6 weeks, but the effect was transientAutism (ASD): Kang 2017 *Microbiome*, n=18 — reported symptom improvement, but it was open-label with no control group, which is exactly the design that cannot separate a real effect from expectation and natural fluctuation. The same page warns you not to trust DIY FMT; this study is why the research version isn't settled eitherDepression / anxiety: early stageMultiple sclerosis: early research
Why FMT can do what a probiotic cannot — it is a different kind of intervention, not a larger dose of the same one:
1. Transfers the full microbial community — 1,000+ species including unculturable ones; a probiotic capsule has 1-16 strains
2. Transfers bacterial metabolites — short-chain fatty acids, vitamins, bile-acid metabolism already running
3. Transfers the 'home' — mucin, peptidoglycan, fungal components, phages
4. Transfers a pre-selected community that has already worked in another healthy individual
Delivery methods: colonoscopy / enema (traditional, direct colonization); nasojejunal tube (NJ tube, upper-GI delivery); frozen capsules (oral 'crapsules', now in many hospitals); donor stool banks (OpenBiome in the US; similar in other countries).
Risks: pathogen transmission requires strict donor screening (HIV / HBV / HCV / parasites / multi-drug-resistant organisms). In 2019 two immunocompromised US recipients of stool from the same donor developed ESBL-producing *E. coli* bacteremia and one of the two died (DeFilipp 2019 *NEJM*) — often mis-retold as 'two deaths'. FDA upgraded screening standards in response. Long-term effects remain unknown — does FMT transplant metabolic tendency, behavior, or immunity? Active research.
The current consensus is that FMT is not 'general wellness' — it is a specific medical treatment under regulatory oversight. Don't trust any 'DIY FMT' or 'home stool transplant' clinic.
适应症 · 已批准的与研究中的
粪菌移植 (FMT, Fecal Microbiota Transplantation) 听起来恶心, 但它是现代医学里少有的整生态系移植 + 单一适应症治愈率 80-90% 的方案。已 FDA / NICE 批准的适应症: 复发性艰难梭菌感染 (recurrent C. difficile) 是金标准。标准抗生素治疗后复发 3+ 次, FMT 治愈率 80-90% (van Nood 2013 *NEJM* 经典 RCT, 因为效果太好被提前终止)。美国 2022 年 FDA 批准首个粪菌来源的活体生物药 RBX2660 (Rebyota) —— 注意它是直肠灌肠用的混悬液, 不是胶囊; 2023 年的 SER-109 (Vowst) 才是首个口服胶囊剂型。
研究中适应症 (B-C 级):
IBD (溃疡性结肠炎): FMT 缓解率部分 RCT 阳性, 但需要多次 + 高频次IBS-D (腹泻型): 小型 RCT 显示症状改善代谢综合征、胰岛素抵抗: Vrieze 2012 *Gastroenterology* 显示瘦人粪移植给胖人 6 周后胰岛素敏感性提升, 但效应短暂自闭症 (ASD): Kang 2017 *Microbiome* 18 个孩子的小型研究报告了症状改善, 但它是开放标签、没有对照组——这正是那种分不清真效果和期待加自然波动的设计。这一页后面叫你别信自助 FMT; 而研究版本本身也还没定论, 原因就在这里抑郁、焦虑: 早期阶段多发性硬化: 早期研究
kang-2017-microbiome-mtt-autism
机制 · 整套能成, 单株不能
为什么 FMT 做得到、单株益生菌做不到 —— 它不是剂量更大的益生菌, 而是另一类干预:1. 传递完整菌群: 1000+ 菌种, 包括不可培养菌; probiotic 胶囊只有 1-16 株
2. 传递菌代谢产物: 已经在做 short-chain fatty acids: Small molecules (acetate/propionate/butyrate) gut bacteria make from fiber — they feed the gut lining and calm inflammation.、维生素、胆汁酸代谢
3. 传递菌的家: 黏液、肽聚糖、真菌组分、噬菌体
4. 传递宿主已经选好的菌群组合: 这套已经在另一个健康个体身上工作过
这四条其实是同一条: 它带过来的是一个已经在运转的系统, 而不是一个零件。
拿合租房打比方。补一株菌, 是让一个陌生人拎着行李站在走廊上: 没有空床、没有他能吃的那份饭、原住户还联手排挤他, 于是他待几天就走了——这正是前面几幕反复讲的那个过路。FMT 不是让他挤进去, 是整屋人连同他们的秩序一起搬进来: 谁睡哪张床、谁买菜谁做饭、垃圾谁倒, 这套分工是跟着人一起来的。所以它落得下脚。
顺着这条推理往下走, 立刻能得到两个判断:
为什么它最硬的适应症恰好是那一个。 反复用强抗生素打过之后, 常驻菌所剩无几, 艰难梭菌把地盘全占了。这时候房子是空的 (确切说是被一个恶房客独占), 搬进来一整屋健康住户才挤得动它。为什么它至今没有变成一种保健手段。 在一个菌群完好的人身上做同一件事, 没有那个杠杆——房子满着, 换住户既没必要, 风险也不成比例。
所以 FMT 和益生菌的差别不是强弱, 而是能不能定植这个二选一的问题。理解了这一点, 你也就知道为什么货架上没有、也不该有家用版 FMT。
途径与风险 · 为什么必须在监管下做
FMT 的实施方式: 结肠镜、灌肠 (传统, 直接定植); 鼻空肠管 (NJ tube, 上消化道进入); 冷冻胶囊 (粪丸, 患者口服, 越来越多医院在用); 来自商业粪便库 (OpenBiome 美国, 类似公司在多国出现)。风险: 病原传播需要严格筛查供者 (HIV / HBV / HCV / 寄生虫、多药耐药菌等); 2019 年美国有 2 例免疫抑制患者因同一供体的粪便发生多重耐药 (ESBL) 大肠杆菌血流感染, 其中 1 例死亡 —— FDA 因此升级了筛查标准。⚠️ 这条常被转述成2 例死亡, 但原始通报和 NEJM 的报告都是2 例感染 / 1 例死亡; 长期效应仍是未知, 移植了代谢倾向、行为或免疫? 还在研究。
目前的共识是 FMT 不是普通保健, 而是特定适应症的医学治疗, 必须在监管下进行。不要相信任何自助 FMT 或家用粪菌 诊所。
Future of microbiome medicine
The microbiome field's evolution from 2010 to 2025, and the limitations of the probiotic era.First-generation probiotics (1900-2000s): the concept was to add a single 'good bacterium' to repair the gut; in practice most strains didn't colonize, individual variation was large, and clinical effects were small — represented by yogurt cultures and generic commercial probiotics.
Second-generation probiotics (2010-2020s): the concept shifted to strain-specific + indication RCT validation; in practice products like LGG, *S. boulardii*, and *B. infantis* 35624 became evidence-based options — what actually landed is the handful of situations guidelines give a conditional yes to (pouchitis, *C. difficile* prevention while on antibiotics, NEC prevention in preterm low-birth-weight infants), not the generic blends on the shelf.
Third generation — microbiome therapeutics (2022+):
Standardized stool-derived products: Rebyota (2022, rectal suspension) / Vowst (2023, oral capsule)Next-generation probiotics (NGP) beyond lactic-acid bacteria and bifido — *Akkermansia muciniphila* (Cani lab work) and *Faecalibacterium prausnitzii* (a major anti-inflammatory strain)Synthetic designed consortia: dozens of strains engineered togetherBacteria + metabolite combinations (the postbiotic concept): a probiotic plus its key metabolites
Personalized microbiome medicine (active research): testing your own microbiome composition (uBiome went under, Viome continues), but clinical utility is very limited — knowing what bacteria you have doesn't tell you what to supplement. Microbiome-based disease prediction: anti-PD-1 immunotherapy response is partly predicted by gut bacteria (Routy 2018 *Science*); drug responses to digoxin and chemotherapy are influenced by gut microbes (Haiser 2013 *Science*).
Most likely directions for the next 5-10 years:
More FDA-approved microbiome therapeutics (live biotherapeutic products, LBPs)NGPs going mainstream (*Akkermansia* already commercialized via the Lacroix team)Microbiome + drug combination therapy (paired with immunotherapy or chemotherapy)Precision probiotics — selection + tracking based on individual microbiome + indication
At the household-daily level, however, the next 5 years are unlikely to bring large change: the best move for healthy people remains a diverse diet + fermented foods + high fiber — not outdated, but a cheap, practical solution repeatedly validated over 30+ years of research.
Final operating psychology: the probiotic industry is $70B+ per year, and massive commercial interest inflates the 'insurance use' concept. The gap between reality and marketing is large; spending a bit more time on information consumption has a far better ROI than supplement consumption.
Chapter 6
Practical · should I / how
Practical · should I / how
The most practical decision tree.
Q1: Do I have a specific clinical indication?
On antibiotics or just finished: *S. boulardii* 250 mg ×2/day, or LGG 10¹⁰ CFU/day, spaced 2 h from the antibioticTraveling to a developing country: this site has no citation supporting that use, so it doesn't belong on this list — water and food hygiene plus packing oral rehydration salts is what actually helpsRecurrent IBS: you can try *B. infantis* 35624 (Align) × 4 weeks — stop if it doesn't work. Note this is 'try', not 'follow the guideline': AGA 2020 makes no recommendation for IBSAcute infectious diarrhea in children: rehydration is the treatment; probiotics are not. Pooled in Cochrane 2020 the duration difference crosses zero (8.64 hours shorter, range 29 hours shorter to 12 hours longer, very low certainty), and AGA 2020 suggests against it. Put the money and the attention into oral rehydration saltsRecurrent vaginosis / UTI in women: *L. rhamnosus* GR-1 + *L. reuteri* RC-14High-risk family allergy prevention during pregnancy / infancy: LGG, used in late pregnancy and infancy
Q2: I just want to 'tune my gut.'
You don't need a probiotic capsule; these three are more effective:
1. 1-2 different fermented foods daily (yogurt, kefir, kimchi, natto)
2. 25-40 g fiber daily, 30+ different plant species per week
3. Fewer antibiotics, less ultra-processed food
Money spent at the produce market has a better ROI than at the pharmacy.
Q3: I've heard probiotics support immunity / anti-aging.
These indications have weak evidence; continuing to take them just means you've been persuaded by marketing rather than science. Energy is better spent on sleep, exercise, waist reduction, and stress management — the things with strong evidence.
How to take — key points:
Take with or after meals: food buffers acid and provides nutrients for the bacteriaSpace 2-4 h from antibiotics — otherwise the antibiotic also kills the probioticKeep refrigerated products refrigerated; keep shelf-stable products cool — don't leave them in a hot carTake continuously for at least 4 weeks — effects usually need time to accumulate; if one strain doesn't work, try anotherDon't mix multiple brands at once — wasteful and you can't tell which is doing whatAfter symptoms improve, taper gradually or switch to fermented foods for maintenance
Red flags (stop and see a doctor):
Bloating or diarrhea worsens rather than improves — not the right fitFever, chills, persistent discomfort: emergency evaluation (rare bacteremia)Critically ill / immunosuppressed / central venous line / severe pancreatitis: pause and don't self-administer
Wellness-grade vs pharmaceutical-grade probiotics: wellness-grade products are loosely regulated by FDA / NMPA and label accuracy varies — choose third-party certified (USP / NSF / ConsumerLab); pharmaceutical-grade probiotics have approved indications, regulation, and RCT data. For everyday use, wellness-grade is usually sufficient; for critical or therapeutic use, look for pharmaceutical-grade.
Q1: Do I have a specific clinical indication?
On antibiotics or just finished: *S. boulardii* 250 mg ×2/day, or LGG 10¹⁰ CFU/day, spaced 2 h from the antibioticTraveling to a developing country: this site has no citation supporting that use, so it doesn't belong on this list — water and food hygiene plus packing oral rehydration salts is what actually helpsRecurrent IBS: you can try *B. infantis* 35624 (Align) × 4 weeks — stop if it doesn't work. Note this is 'try', not 'follow the guideline': AGA 2020 makes no recommendation for IBSAcute infectious diarrhea in children: rehydration is the treatment; probiotics are not. Pooled in Cochrane 2020 the duration difference crosses zero (8.64 hours shorter, range 29 hours shorter to 12 hours longer, very low certainty), and AGA 2020 suggests against it. Put the money and the attention into oral rehydration saltsRecurrent vaginosis / UTI in women: *L. rhamnosus* GR-1 + *L. reuteri* RC-14High-risk family allergy prevention during pregnancy / infancy: LGG, used in late pregnancy and infancy
Q2: I just want to 'tune my gut.'
You don't need a probiotic capsule; these three are more effective:
1. 1-2 different fermented foods daily (yogurt, kefir, kimchi, natto)
2. 25-40 g fiber daily, 30+ different plant species per week
3. Fewer antibiotics, less ultra-processed food
Money spent at the produce market has a better ROI than at the pharmacy.
Q3: I've heard probiotics support immunity / anti-aging.
These indications have weak evidence; continuing to take them just means you've been persuaded by marketing rather than science. Energy is better spent on sleep, exercise, waist reduction, and stress management — the things with strong evidence.
How to take — key points:
Take with or after meals: food buffers acid and provides nutrients for the bacteriaSpace 2-4 h from antibiotics — otherwise the antibiotic also kills the probioticKeep refrigerated products refrigerated; keep shelf-stable products cool — don't leave them in a hot carTake continuously for at least 4 weeks — effects usually need time to accumulate; if one strain doesn't work, try anotherDon't mix multiple brands at once — wasteful and you can't tell which is doing whatAfter symptoms improve, taper gradually or switch to fermented foods for maintenance
Red flags (stop and see a doctor):
Bloating or diarrhea worsens rather than improves — not the right fitFever, chills, persistent discomfort: emergency evaluation (rare bacteremia)Critically ill / immunosuppressed / central venous line / severe pancreatitis: pause and don't self-administer
Wellness-grade vs pharmaceutical-grade probiotics: wellness-grade products are loosely regulated by FDA / NMPA and label accuracy varies — choose third-party certified (USP / NSF / ConsumerLab); pharmaceutical-grade probiotics have approved indications, regulation, and RCT data. For everyday use, wellness-grade is usually sufficient; for critical or therapeutic use, look for pharmaceutical-grade.
决策树 · 说得出名字的那些情况
问 1: 我有具体临床适应症吗?抗生素疗程中或刚结束: S. boulardii 250 mg ×2/天, 或 LGG 10¹⁰ CFU/天, 与抗生素错开 2 小时旅行去发展中国家: 站内没有支持这一条的引用, 所以它不该出现在这张单子上——真正管用的是水和食物卫生, 以及带上口服补液盐IBS 反复发作: 可以试 B. infantis 35624 (Align) × 4 周, 无效就停。注意这是试不是遵指南: AGA 2020 对 IBS 不给推荐儿童急性感染性腹泻: 补液是治疗, 益生菌不是。 Cochrane 2020 汇总后病程差异跨过零 (缩短 8.6 小时, 区间从缩短 29 小时到延长 12 小时, 确定性极低), AGA 2020 对这一条明确不建议。把钱和注意力放在口服补液盐上反复阴道炎 / UTI 女性: L. rhamnosus GR-1 + L. reuteri RC-14高风险家庭孕期或婴儿期防过敏: LGG, 用于孕末和婴儿期
问 2: 我只是想调理肠道?
不需要 probiotic 胶囊, 做这三件事更有效:
1. 每天 1-2 份不同的发酵食品 (酸奶、开菲尔、泡菜、纳豆)
2. 每天 25-40 g 纤维, 每周 30 种以上不同植物
3. 少用抗生素, 少超加工食品
钱花在菜场比药房性价比更高。
问 3: 我听说益生菌能防免疫、抗衰?
这些适应症证据偏弱, 继续吃就是被营销说服, 而不是科学。把精力关注在睡眠、锻炼、减腰围、心理压力这些确实有强证据的事上更划算。
怎么吃 · 每条规则背后的机制
怎么吃 的要点:餐时或餐后服: 食物缓冲胃酸, 也给菌一些养料与抗生素错开 2-4 小时, 否则抗生素同时把 probiotic 也杀掉冷藏品冷藏, 室温品放阴凉处, 不要丢车里晒连续服至少 4 周, 效果通常需要时间累积; 一种无效再换不要同时多品牌混吃, 浪费且观察不出哪个有效症状改善后可以逐渐减量, 或者转向发酵食品维持
这几条不是经验之谈, 每一条都能倒推回前面讲过的机制:
餐时或餐后服: 食物把胃里的强酸稀释、把酸度往上顶一点, 过胃那一关的折损就小一些。同一口饭还顺带给菌带了点口粮。与抗生素错开几小时: 抗生素不认敌我, 你补的菌和它要杀的菌在它眼里长得一样。错开的意思是让肠腔里的药物浓度先降下去, 别让两个东西正面撞上。布拉迪酵母是那个不必错开的例外, 因为它是酵母, 抗生素的枪口对不着它。冷藏品必须冷藏: 活菌是靠一套酶维生的活体, 温度越高酶坏得越快, 到你嘴里时剩下的活菌就越少。丢在太阳底下的车里, 你为之付钱的那个数字就蒸发了。连着吃一段时间: 过路菌不定植, 效果全靠在场。断了就等于人走了, 所以要连着给; 也正因如此, 世上没有吃一个疗程一劳永逸这回事。不要多品牌混吃: 临床证据是一株一株做出来的。混着吃, 你既拿不到任何一株的完整剂量, 也分不清是哪一株在起作用——下一次照样不知道该买什么。好转之后转向发酵食品维持: 症状消下去以后, 你需要的不再是抢占空位的临时工, 而是把常驻菌的工作环境养住。发酵食品和纤维干的正是这件事, 而且不必每天过胃酸那一关。
把这几条连起来看, 它们其实只在说一件事: 你买的是一段在场时间, 不是一次永久改造。所以吃法的每个细节, 都是在让这段在场时间更长、更完整、更容易被你自己观察到。
红旗与产品分级
红旗 (停服并看医生):服用后腹胀或腹泻加重而不缓解, 说明不适合发热、寒战、持续不适: 急诊评估 (罕见菌血症)危重、免疫抑制、中心静脉导管、重症胰腺炎: 暂停, 不要自行使用早产儿: 不要自行给。FDA 2023 年 9 月警告过这一条, 而且美国没有任何一款益生菌被批准用于婴儿; 住院早产儿要不要用, 由新生儿科团队决定
保健级 probiotic vs 药品级: 保健食品类 FDA / NMPA 监管松, 标签准确性差异大, 选第三方认证 (USP / NSF / ConsumerLab); 药品级 (Rx) 有适应症、监管和 RCT 数据。大多数日常用途保健级足够, 危重或治疗用途找药品级。
fda-2023-probiotics-preterm-warning
TL;DR
A few core takeaways:Probiotics aren't a 'good-bacteria supplement' — they're a precision tool requiring a match of strain + indication + time windowFor most people most of the time, food (fermented + fiber + diversity) beats capsulesFMT is the real microbiome therapy, but only for specific indications — don't fall for 'home stool transplant' scams'Insurance-style daily probiotic capsules' aren't needed for most people; spend the money on higher-ROI things (vegetables and fruit, exercise, sleep)
The core wisdom of this island: a healthy gut isn't the result of 'eating more good bacteria' — it's the result of giving the bacteria that already live in you a good working environment.
Good working environment = enough fiber + diverse plants + fewer antibiotics + less ultra-processed food + adequate sleep + stress management.
These are cheap, sustainable long-term, and side-effect-free — the real 'probiotic alternative'.
References · 11
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- Zmora, N., Zilberman-Schapira, G., Suez, J., et al. (2018). Personalized gut mucosal colonization resistance to empiric probiotics is associated with unique host and microbiome features. Cell, 174(6), 1388-1405.e21. 10.1016/j.cell.2018.08.041
- Suez, J., Zmora, N., Zilberman-Schapira, G., et al. (2018). Post-antibiotic gut mucosal microbiome reconstitution is impaired by probiotics and improved by autologous FMT. Cell, 174(6), 1406-1423.e16. 10.1016/j.cell.2018.08.047
- Guo, Q., Goldenberg, J. Z., Humphrey, C., & El Dib, R. (2019). Probiotics for the prevention of pediatric antibiotic-associated diarrhea. Cochrane Database of Systematic Reviews, 4, CD004827. 10.1002/14651858.CD004827.pub5
- Su, G. L., Ko, C. W., Bercik, P., Falck-Ytter, Y., Sultan, S., Weizman, A. V., & Morgan, R. L. (2020). AGA Clinical Practice Guidelines on the Role of Probiotics in the Management of Gastrointestinal Disorders. Gastroenterology, 159(2), 697-705. 10.1053/j.gastro.2020.05.059
- Collinson, S., Deans, A., Padua-Zamora, A., Gregorio, G. V., Li, C., Dans, L. F., & Allen, S. J. (2020). Probiotics for treating acute infectious diarrhoea. Cochrane Database of Systematic Reviews, 2020(12), CD003048. Duration of diarrhoea: mean difference 8.64 hours shorter (95% CI 29.4 hours shorter to 12.1 hours longer; 6 trials, 3058 participants), certainty very low. 10.1002/14651858.CD003048.pub4
- Ford, A. C., et al. (2018). Systematic review with meta-analysis: the efficacy of prebiotics, probiotics, synbiotics, and antibiotics in IBS. Alimentary Pharmacology & Therapeutics, 48(10), 1044–1060. 10.1111/apt.15001
- Wastyk, H. C., et al. (2021). Gut-microbiota-targeted diets modulate human immune status. Cell, 184(16), 4137–4153.e14. 10.1016/j.cell.2021.06.019
- van Nood, E., Vrieze, A., Nieuwdorp, M., et al. (2013). Duodenal infusion of donor feces for recurrent Clostridium difficile. The New England Journal of Medicine, 368(5), 407-415. 10.1056/NEJMoa1205037
- DeFilipp, Z., Bloom, P. P., Torres Soto, M., et al. (2019). Drug-resistant E. coli bacteremia transmitted by fecal microbiota transplant. The New England Journal of Medicine, 381(21), 2043-2050. Two immunocompromised recipients of stool from one donor developed ESBL-producing E. coli bacteremia; one of the two died. 10.1056/NEJMoa1910437
- U.S. Food and Drug Administration. (2023). FDA approves first orally administered fecal microbiota product for the prevention of recurrence of Clostridioides difficile infection [Press release, April 26, 2023]. Vowst is the first oral fecal microbiota product (four capsules once daily for three days); Rebyota, approved 2022, is a rectal suspension. www.fda.gov/news-events/press-announcements/fda-approves-first-orally-administered-fecal-microbiota-product-prevention-recurrence-clostridioides