21st Century Acidophilus Probiotic Blend Review
Our Acidophilus Probiotic Blend contains beneficial live cultures that help maintain a healthy gut flora balance and promote optimal digestive functions. This carefully formulated blend supports immune system health while aiding in nutrient absorption. The page describes it as a daily acidophilus capsule for adults. Listed benefits include promoting digestive function and helping maintain regularity for daily digestive comfort, maintaining healthy gut flora balanced to support a balanced microbiome, providing 1 billion live probiotic cultures, and helping strengthen natural defenses of the immune system. It is presented as an essential probiotic blend to support gut health from within, with a probiotic blend for digestive and intestinal support and prebiotic inulin for probiotic and immune system health. The product page states that Acidophilus Probiotic Blend contains Lactobacillus acidophilus, a friendly bacteria for the digestive system, synergistically combined with three other genetically distinct probiotic organisms and the prebiotic Inulin, to promote healthy probiotic activity and immune system health. The footnote states 1 billion active cultures per serving guaranteed at time of manufacture. The directions say adults take one capsule daily with any meal or as directed by a healthcare provider, and not to exceed the recommended dosage. Individual results may vary. The warnings advise consulting a healthcare provider before use if pregnant, nursing, on medications, having a medical condition, or planning a medical procedure, and to stop use and contact a physician if adverse reactions occur. The product should be refrigerated after opening and kept out of reach of children. The page lists the product as gluten free and non-GMO, with no added sugar, salt, preservatives, artificial flavors or artificial colors. The page also says the product is available in 100, 150 and 300 capsule sizes. The brand, 21st Century Vitamins, says it has provided trusted supplements for over 30 years and that products undergo rigorous testing. The page notes that the information may differ from the product purchased, so the supplement facts on the package label should be checked.
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Supplement Facts
Proprietary Blend Containing 1 billion live cultures† Lactobacillus acidophilus, Lactobacillus salivarius, Bifidobacterium bifidum, Streptococcus thermophilus 175 mg
| Proprietary Blend Containing 1 billion live cultures† Lactobacillus acidophilus, Lactobacillus salivarius, Bifidobacterium bifidum, Streptococcus thermophilus | 175 mg | † |
Other ingredients: Whey, Inulin, Gelatin, Cellulose, Citrus Pectin. Contains <2% of: Magnesium Stearate, Silicon Dioxide. Contains milk (whey).
Directions: As a dietary supplement, adults take one (1) capsule daily with any meal or as directed by a healthcare provider. Do not exceed recommended dosage. Individual results may vary.
Label source: 21stcenturyvitamins · Report a label change
Where to Buy
21st Century · iHerb · Walmart
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Graded October 28, 2026 by the Reverse Age Lab evidence engine, from human studies, real reviews and our biohacker panel. How we grade. Is this medical advice? No. Rala organizes the published evidence; go over any change with your doctor, especially if you take meds.

