Probiotics are live microorganisms that provide a health benefit when consumed in sufficient amounts. Among the most recognized probiotics is the group of bacteria known as Lactobacilli. These bacteria are frequently included in various health supplements and fermented foods.
Understanding Lactobacilli as Probiotics
Lactobacilli are a group of bacteria characterized as Gram-positive, rod-shaped, and are facultative anaerobes, meaning they can survive with or without oxygen. A defining feature is their ability to ferment carbohydrates and produce lactic acid as a primary byproduct. These bacteria are a natural part of the microbial communities in humans and animals, commonly inhabiting the digestive and urogenital tracts.
They are also the microorganisms responsible for fermentation in foods like yogurt and sauerkraut. However, not all Lactobacillus species or strains qualify as probiotics. To be designated a probiotic, a specific strain must be a live microorganism that confers a scientifically validated health benefit to the host when administered in adequate quantities. This distinction is important; while the genus Lactobacillus includes hundreds of species, only particular strains have been researched to confirm their probiotic effects.
The Working Principles of Lactobacilli Probiotics
Lactobacilli probiotics employ several methods to support health once established in the gut. One mechanism is competitive exclusion, where they compete with pathogenic bacteria for both nutrients and physical attachment sites on the intestinal lining. By occupying these spaces, they make it more difficult for pathogens to gain a foothold and multiply.
These beneficial bacteria also produce substances that create an unfavorable environment for pathogens. The production of lactic acid lowers the pH in the intestine, making it more acidic and inhibiting the growth of many harmful microbes. Some strains of Lactobacilli also generate antimicrobial compounds called bacteriocins, which can directly target and suppress pathogenic bacteria.
Furthermore, Lactobacilli contribute to the integrity of the gut’s physical barrier. They can stimulate the production of mucin, a key component of the mucus layer that lines the intestines, and help reinforce the “tight junctions” between intestinal cells to prevent unwanted substances from leaking into the bloodstream.
Finally, Lactobacilli interact with and help shape the host’s immune system. They influence the activity of immune cells in the gut, which can lead to a more balanced immune response, and break down dietary components into beneficial compounds like short-chain fatty acids (SCFAs).
Prominent Lactobacilli Strains and Their Health Contributions
The health benefits of probiotics are highly dependent on the specific strain of bacteria, as different strains have unique properties and functions. Several strains have been extensively researched for their contributions to human health.
- Lactobacillus rhamnosus GG (LGG) is one of the most studied probiotic strains. Research has shown it can be effective in managing certain types of diarrhea, particularly diarrhea associated with antibiotic use, and it also plays a role in supporting immune function.
- Lactobacillus acidophilus NCFM is another well-documented strain often associated with digestive health. It is used to address symptoms of lactose intolerance and has been studied for its potential to alleviate symptoms of irritable bowel syndrome (IBS).
- Lactobacillus reuteri, particularly the strain DSM 17938, has been investigated for its benefits in infants, showing promise in reducing crying time associated with colic.
- Lactobacillus plantarum 299v is a prominent strain noted for its connection to improving symptoms of IBS, such as bloating and gas, and for its ability to support gut barrier function.
- Lactobacillus casei Shirota has been studied for its role in digestive regularity and its influence on the immune system.
Finding and Choosing Your Lactobacilli Probiotic
Lactobacilli probiotics can be obtained through two main sources: fermented foods and dietary supplements. Foods like yogurt, kefir, sauerkraut, and kimchi are natural sources of these bacteria, but not all fermented foods contain live probiotic strains, as pasteurization can kill the microbes.
For those seeking a more targeted dose, supplements are available in various forms. When selecting a supplement, look for products that clearly identify the specific probiotic strain on the label, such as Lactobacillus rhamnosus GG.
The potency of a probiotic supplement is measured in Colony Forming Units (CFU), which indicates the number of viable bacteria per dose. Many supplements contain between 1 billion and 50 billion CFUs. Checking for an expiration date and storage instructions is also important, as some probiotics require refrigeration.
Before beginning a new supplement regimen, consulting with a healthcare professional is recommended, especially for individuals with underlying health conditions, compromised immune systems, and pregnant or breastfeeding women.