Supplements for Gut Health: Probiotics, Prebiotics, and What Actually Works

Different probiotic strains treat different conditions, and taking a random multi-strain probiotic is like throwing darts blindfolded. Here's what the evidence actually supports for specific issues.

For antibiotic-associated diarrhea: Saccharomyces boulardii (250-500mg daily) during and 1 week after antibiotics. This is a yeast-based probiotic, so antibiotics don't kill it. Strong evidence from multiple meta-analyses.

For IBS: Bifidobacterium infantis 35624 (Align) and Lactobacillus plantarum 299v have the most IBS-specific evidence. Not all IBS subtypes respond the same way. IBS-D (diarrhea-dominant) tends to respond better to probiotics than IBS-C.

For general digestive maintenance: Lactobacillus rhamnosus GG and Lactobacillus acidophilus are the most studied strains with broad digestive benefits. Look for at least 10 billion CFU.

Key point: a probiotic with 15 strains at 50 billion CFU total isn't necessarily better than a single targeted strain at 10 billion CFU. More is not always more.

Prebiotics feed your existing good bacteria. They're arguably more important long-term than probiotics because they support the ecosystem you already have. Think of probiotics as adding seeds to a garden. Prebiotics are the fertilizer.

Best prebiotic options: partially hydrolyzed guar gum (PHGG, 5g daily) has strong IBS evidence. Acacia fiber is well-tolerated. Inulin and FOS feed bifidobacteria specifically but can cause gas if you ramp up too fast.

L-Glutamine (5-10g daily) is used for intestinal permeability ("leaky gut"). It's the primary fuel source for intestinal cells. Hospitals use it for gut recovery after surgery. The evidence for everyday "leaky gut" supplementation is moderate but growing. If you have IBD or post-infectious IBS, it's worth considering.

A note about "leaky gut": increased intestinal permeability is a real, measurable phenomenon. But the supplement industry has turned it into a catch-all diagnosis. If you suspect gut permeability issues, work with a gastroenterologist. Don't just self-treat based on a wellness blog.

Digestive enzymes (for people without pancreatic insufficiency): your body makes its own. Unless you have a diagnosed enzyme deficiency, supplemental enzymes are probably unnecessary.

Apple cider vinegar: the internet loves it for gut health. The evidence is thin. It might help blood sugar slightly but it won't fix your microbiome.

Bone broth as a "gut healing" supplement: it's food. Fine food. But the collagen content is inconsistent and below therapeutic doses. Eat it if you enjoy it. Don't count on it as medicine.

Detox and cleanse products: your liver and kidneys are your detox system. They work 24/7 for free.