HOWARU® Strains Help Support Respiratory Health

Pollution, allergies and upper respiratory tract illnesses are growing concerns worldwide. HOWARU® probiotic solutions support overall immune health and bolster healthy respiratory function in adults.

Study Aim

To determine if daily intake of a formulation containing Bifidobacterium lactis Bl-04™ would have a positive impact in the prevention of upper respiratory tract illness (URTI) episodes

Study Design

5-month, double-blind, placebo controlled 

Study Method

310 healthy, physically active adults randomized to two treatment groups*:

  • Placebo
  • Bl-04™ (2 Billion CFU)

*An additional probiotic formula was investigated in this study, but results are not reported here.

Evaluation of symptoms and physical activity were conducted via Web-based questionnaire. The signs and symptoms of URTI included a scratchy throat, sore throat, sneezing, stuffy nose, or runny nose. A diagnosis of URTI was made when two or more symptoms were recorded for three or more consecutive days.

Study Results

Bl-04™ Was Associated With Decreased Risk of URTI Episodes

Change in colonic transit time over 14 days by study group. Values represent mean ± 95% confidence interval.
  • Subjects taking Bl-04™ had 27% less risk of experiencing URTI episodes compared to placebo (P=0.02).

Study Aim

To study the effect of B. lactis Bl-04™ on innate and adaptive immune responses, and nasal rhinovirus load for 5 days following a rhinovirus challenge infection.

Study Design

Randomized, double-blind, placebo controlled 

Study Method

115 healthy adults were randomized to two treatment groups:

  • Placebo
  • Bl-04™ (2 billion CFU)
  • All participants challenged with nasal application of rhinovirus

Markers of immune function (interleukin 8 and other cytokines) and rhinovirus levels were measured from nasal washes as well other endpoints.

Study Results

Bl-04™ Reduced the Amount of Rhinovirus in Nasal Mucosa

  • Bl-04™ supplementation decreased the amount of rhinovirus in nasal washes during the 5 days following a rhinovirus challenge compared to placebo (P=0.026).

Additional Study Information
West NP, et al. Clin Nutr. 2014;33(4):581-587.
Turner RB, et al. Benef Microbes. 2017;8(2):207-215.


1. West NP, Horn PL, Pyne DB, et al. Probiotic supplementation for respiratory and gastrointestinal illness symptoms in healthy physically active individuals. Clin Nutr. 2014;33(4):581-587.

2. Turner RB, Woodfolk JA, Borish L, et al. Effect of probiotic on innate inflammatory response and viral shedding in experimental rhinovirus infection – a randomized controlled trial. Benef Microbes. 2017;8(2):207-215.

When adult patients need immune support, recommend clinically researched HOWARU® strains  
The information on this site is intended for healthcare professionals in the United States and is not intended for the general public.