Lactobacillus rhamnosus is a probiotic bacterium found naturally in the human digestive system. It is uniquely adapted to survive passage through the acidic conditions of the stomach to colonize the intestines. While available as a supplement, this article focuses on common foods that provide this bacterium through your diet.
Common Food Sources of Lactobacillus Rhamnosus
The most prevalent sources of Lactobacillus rhamnosus are in the dairy aisle. Yogurt and kefir are primary examples, as many manufacturers add specific strains, like Lactobacillus rhamnosus GG, to their products to ensure a consistent presence. The dairy matrix helps buffer the bacteria from stomach acid, improving its survival rate as it travels to the intestines.
Beyond yogurt and kefir, certain types of cheese can also contain this bacterium. It is sometimes used in the cheesemaking process to aid in ripening and flavor development. Soft cheeses are more likely to harbor live cultures, and specific varieties such as Gouda have been noted to sometimes contain L. rhamnosus. However, its presence is not guaranteed unless the manufacturer explicitly states it on the packaging.
Fermented vegetable dishes are another source of Lactobacillus rhamnosus. Traditional preparations of kimchi and sauerkraut often develop a wide array of lactic acid bacteria during fermentation, which can include L. rhamnosus. The specific microbial composition of these foods can vary based on the recipe and environmental conditions.
Other fermented beverages and foods may also contain this probiotic. Sourdough bread, for instance, relies on a starter culture of wild yeasts and lactobacilli, which can include L. rhamnosus. Miso, a fermented soybean paste, is another potential source. While the popular fermented tea drink kombucha is rich in probiotics, L. rhamnosus is less commonly a dominant strain unless it is specifically added by the producer during manufacturing.
Health Benefits Associated with Lactobacillus Rhamnosus
One of the most researched attributes of Lactobacillus rhamnosus is its positive influence on digestive health. It contributes to a balanced gut microbiome by producing lactic acid, which helps inhibit the growth of less beneficial bacteria. This action is particularly helpful in managing certain types of diarrhea. Studies have shown that supplementing with the GG strain can reduce the risk of developing diarrhea associated with antibiotic use. It may also lessen the duration of other forms, such as traveler’s diarrhea.
A healthy gut environment is closely linked to the body’s immune function, and L. rhamnosus supports this connection. By reinforcing the gut barrier, this probiotic can help modulate immune responses. Some research has pointed to its ability to reduce the occurrence of mild upper respiratory tract infections in children.
Beyond digestion and immunity, emerging research suggests other potential benefits. For example, some studies have investigated the link between specific strains and skin health. The strain L. rhamnosus HN001 has been studied for its potential to help reduce the risk of eczema in young children with a family history of the condition when taken by the mother during pregnancy and breastfeeding. Other research has explored its role in alleviating symptoms associated with irritable bowel syndrome (IBS), such as abdominal pain and bloating, though more human studies are needed to form conclusive recommendations.
Identifying Lactobacillus Rhamnosus on Food Labels
Finding Lactobacillus rhamnosus in a product requires looking closely at the food label, as its presence is not always guaranteed, even in fermented foods. The most direct method is to read the ingredients list. Food manufacturers who add specific probiotics will typically list them by their scientific name. You should look for the words “Lactobacillus rhamnosus” printed on the packaging, often found in a section describing the “live and active cultures.”
For greater assurance, look for the specific strain designation, which indicates a higher level of quality control. The most extensively researched and commonly used strain is Lactobacillus rhamnosus GG, often abbreviated as “LGG”. Seeing this specific name in the ingredients list means the manufacturer has used a strain with a documented history of scientific study. Other strains, such as HN001 or GR-1, may also be listed and are associated with different researched benefits.
Consumers may notice a “Live & Active Cultures” seal, particularly on yogurt products. This seal, created by the National Yogurt Association, certifies that the yogurt contained at least 100 million cultures per gram at the time of manufacture. While this indicates the product is a good source of probiotics, it does not specify which types are present. Therefore, even with the seal, it is still necessary to check the ingredients to confirm the presence of L. rhamnosus specifically.