The Effectiveness of Lactobacillus Beverages in Controlling Infections among the Residents of an Aged Care Facility: A Randomized Placebo-Controlled Double-Blind Trial

Ann Nutr Metab. 2016;68(1):51-9. doi: 10.1159/000442305. Epub 2015 Nov 25.


Backgrounds/aims: To clarify the usefulness of Lactobacillus casei strain Shirota (LcS)-fermented milk in the normalization of bowel movements and improvement of infection control for the elderly residents and staff of facilities for the elderly.

Methods: A randomized placebo-controlled double-blind test was performed among the elderly residents (average age, 85) and staff members (average age, 37) of facilities for the elderly. The participants randomly received either LcS-fermented milk or a placebo beverage once daily for 6 months. Clinical data and enteric conditions were compared between the 2 groups.

Results: A significantly lower incidence of fever and improved bowel movements were seen in the LcS-fermented milk group (n = 36) in comparison to the placebo group (n = 36). The numbers of Bifidobacterium and Lactobacillus were significantly higher (p < 0.01), the numbers of destructive bacteria such as Clostridium difficile were significantly lower (p < 0.05), and the fecal acetic acid concentration and total acidity were significantly higher in the LcS group. A significant difference in the intestinal microbiota, fecal acetic acid, and pH was also observed between the LcS and placebo groups among the facility's staff members.

Conclusions: The long-term consumption of LcS-fermented milk may be useful for decreasing the daily risk of infection and improving the quality of life among the residents and staff of facilities for the elderly.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetic Acid / analysis
  • Adult
  • Aged
  • Aged, 80 and over
  • Beverages / microbiology*
  • Bifidobacterium
  • Body Mass Index
  • Clostridioides difficile / isolation & purification
  • Communicable Diseases / therapy*
  • Cultured Milk Products / microbiology*
  • Double-Blind Method
  • Feces / chemistry
  • Feces / microbiology
  • Female
  • Humans
  • Hydrogen-Ion Concentration
  • Lacticaseibacillus casei*
  • Male
  • Middle Aged
  • Probiotics / administration & dosage*
  • Quality of Life


  • Acetic Acid