How to choose a good acidophilus supplement

A good acidophilus supplement names an exact strain (not just the species), states its CFU count guaranteed through the end of shelf life rather than only at manufacture, matches a dose that's actually been tested in a human trial for whatever you're taking it for, and discloses its other ingredients plainly. Most products on the market fall short of at least one of these.

Look for a named strain, not just the species

"Lactobacillus acidophilus" is a species name; a strain code after it — NCFM, DDS-1, La-14, and others — identifies the specific, genetically distinct organism a manufacturer is actually using. Closely related strains can differ enough in their genes that a research finding for one doesn't transfer to another, so a label that only says "Lactobacillus acidophilus" with no strain code gives you no way to connect it to any specific trial. See what is acidophilus for why strain identity matters this much.

Check how the CFU count is guaranteed

Live bacteria can lose potency in storage, so the number that matters is the CFU count guaranteed through the end of shelf life, not the count at the moment of manufacture — a label should say which one it's reporting. If a label states a number with no mention of when it was measured, that's a gap worth noting, not a reason to assume the worse.

Match the dose to what's actually been studied

See acidophilus dosage for the specific CFU amounts used in human trials of named strains — they range from about 10 billion to 200 billion CFU a day, depending on the strain and what was being tested. A product with a much lower CFU count than any trial of its named strain used isn't necessarily useless, but it also isn't backed by the specific research you might be relying on when you buy it.

Read past the species name on a blend

Products labeled "acidophilus & bifidus" or "probiotic blend" contain acidophilus alongside other species — check the full ingredient list and the CFU count attributed to acidophilus specifically, since a blend's total CFU count can be split unevenly across several organisms. A trial of a blend also doesn't tell you what acidophilus contributed on its own, or vice versa.

Check the format and other ingredients

Some products are shelf-stable at room temperature; others need refrigeration to stay viable — follow the storage instructions on the specific product you buy, since a live-bacteria supplement stored the wrong way can lose potency before you take it. Check the other listed ingredients too: a capsule shell made of gelatin isn't vegan even if the probiotic culture itself is, and any allergen statement (some cultures are grown on a dairy- or soy-based medium) is worth reading if you have a relevant allergy.

Compare price per serving, not price per bottle

Divide a product's price by the number of servings in the bottle to get a price-per-serving figure you can actually compare across brands — a bigger bottle or a higher CFU count isn't automatically a better value if the price per serving is also higher.

Look for testing, if it's offered

Some manufacturers publish a certificate of analysis (COA) from an independent lab confirming the CFU count and strain identity match the label. Not every brand offers one; if a brand does, it's worth checking that the COA is for the actual product and lot you're considering, not a general claim about the company.

Questions people ask

Where can I buy acidophilus?

It's sold as a capsule, tablet or powder through most pharmacies, health food stores and online retailers, usually in the probiotic or digestive-health section. The checklist above applies regardless of where you buy it.

Which acidophilus is best?

There's no single "best" acidophilus — the right choice depends on which named strain and dose matches what a person is actually looking for, checked against the specific trials in acidophilus benefits, not a general ranking.

What is acidophilus milk, and can I buy that instead of a supplement?

Acidophilus milk is a fermented dairy food, not a supplement, and it isn't required to state a CFU count — see what is acidophilus for how the two compare.

Related reading: acidophilus dosage and acidophilus benefits: what the research does and doesn't show.