Choose yogurt and kefir with live active cultures

Buy yogurt and kefir labeled "live and active cultures." Plain, unsweetened varieties are best. Kefir is the most microbially diverse option with 30+ strains compared to 2-5 in most yogurts.

Why It Works

Yogurt is the most studied fermented food, with evidence for improved lactose digestion and immune benefits. Kefir contains both bacteria and yeasts in a symbiotic community, providing broader microbial diversity per serving. Both deliver live organisms directly to the gut alongside fermentation metabolites.

Tips

• Greek yogurt is strained but still contains live cultures — check the label
• Flavored yogurts often contain high sugar and fewer live cultures — add your own fruit instead
• Kefir is drinkable and easy to add to smoothies or pour over granola
• Goat and sheep milk versions are available for those sensitive to cow dairy