Probiotic
Quick Definition
Live beneficial microorganisms that, when consumed in adequate amounts, confer health benefits to the host.
In-Depth Explanation
Probiotics are live microorganisms -- primarily bacteria from the Lactobacillus and Bifidobacterium genera, as well as the yeast Saccharomyces boulardii -- that provide health benefits when consumed in sufficient quantities.
Scientific evidence supports probiotic use for antibiotic-associated diarrhea, infectious diarrhea, irritable bowel syndrome (IBS), and certain allergic conditions. Emerging research explores their role in mental health (psychobiotics), skin health, and weight management.
Probiotics are found in fermented foods like yogurt, kefir, sauerkraut, kimchi, miso, tempeh, and kombucha. When choosing supplements, specific strains matter -- different strains have different effects. Colony-forming units (CFUs) indicate the number of viable bacteria, with most effective supplements containing 1-10 billion CFUs. Probiotics work best alongside prebiotics (dietary fiber that feeds beneficial bacteria).