Probiotics are beneficial bacteria (sometimes referred to as "friendly germs") that help to maintain the health of the intestinal tract and aid in digestion. They also help keep potentially harmful organisms in the gut (harmful bacteria and yeasts) under control. Most probiotics come from food sources, especially cultured milk products. Probiotics can be consumed as capsules, tablets, beverages, powders, yogurts and other foods.
Research suggests that probiotics, especially those in milk or food, may help boost the immune system. However, commercially produced yogurt may not be as effective. More studies are needed, particularly with yogurt, in order to reach a firm conclusion.
In a new study, researchers randomly assigned 737 healthy elderly individuals from 53 nursing homes to receive probiotics in the form of two bottles of fermented milk or a placebo drink containing no probiotics daily for 176 days. All participants also received a flu shot on day 21. Several outcome measures, including respiratory symptoms and immune response to the flu shot were evaluated.
The researchers found that the consumption of probiotics had no significant effect on respiratory symptoms or immune response to the flu shot. Additional research is necessary in this area.
For more information about probiotics, please visit Natural Standard's Health & Wellness Database.
For more information about integrative therapies for cold and flu prevention, please visit Natural Standard's Comparative Effectiveness Database.