Postbiotics (heat-killed probiotics)
What it is
Heat-killed bacterial preparations that provide immune and gut benefits without live organisms. The advantage is perfect shelf stability with no need for refrigeration. A 2024 review of 8 trials found heat-killed Lactobacillus preparations significantly reduce respiratory infection incidence and duration. The ISAPP scientific association formally defined postbiotics in 2021. Still an emerging category with less evidence than live probiotics.
Dose
1–10 billion heat-killed cells/day (e.g., HK L-137 250 mg/day, ET-901 100 mg/day). Take any time of day with or without food — shelf-stable, no refrigeration needed.
Time of day & tips
Take 1× daily, any time of day, with or without food — shelf-stable, no refrigeration needed. Can be combined with live probiotics. Consistency over weeks matters more than timing.
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