Lactobacillus casei (L. casei) is a beneficial probiotic microorganism. These “good” bacteria reside naturally in the human digestive tract, maintaining a balanced gut environment. Though reclassified as Lacticaseibacillus casei in 2020, it’s still widely known as Lactobacillus casei, the name used here. L. casei helps break down food, absorb nutrients, and manage other gut microorganisms.
Where to Find L. casei
L. casei is found in various fermented foods. Many probiotic yogurts contain L. casei. Certain fermented dairy products, like Gouda cheese, also contain it.
Beyond dairy, it’s in fermented vegetables like sauerkraut and kimchi. Other sources include miso and sourdough bread. These foods provide L. casei as part of a complex microbial community.
L. casei is also available in dietary supplements. Supplements often feature specific strains like L. casei Shirota or L. casei DN-114001. Available as powders and capsules, supplements deliver a concentrated amount of these bacteria.
Health Benefits of L. casei
L. casei contributes to digestive well-being by regulating gut processes. It helps maintain a balanced gut microbiota by producing antimicrobial substances, like bacteriocins, which inhibit harmful bacteria. This supports a healthy intestinal environment and can improve gut regularity.
It has shown promise in managing various forms of diarrhea, including antibiotic-associated, infectious, and traveler’s diarrhea. Studies show L. casei can reduce the incidence and duration of acute diarrhea, especially in children. It also helps alleviate symptoms like abdominal bloating and discomfort by supporting proper food transit.
Beyond digestive support, specific L. casei strains have been explored for chronic constipation. Regular intake of milk fermented with L. casei Shirota has improved bowel habits for those with constipation. Research also suggests benefits for Irritable Bowel Syndrome (IBS) symptoms, as L. casei may help modulate gut microbiota and reduce abdominal pain.
L. casei also benefits the immune system. Certain strains can modulate the innate immune system, enhancing defense mechanisms. This includes increasing the activity of natural killer (NK) cells, part of the immune response against infected cells. It also supports gut barrier function, a physical defense preventing unwanted substances from crossing into the bloodstream.
L. casei may help regulate inflammatory responses. Studies indicate its potential in alleviating allergy symptoms and inflammation by modulating immune responses. This anti-inflammatory action may support overall well-being.
Important Considerations for L. casei
L. casei is generally safe for most healthy individuals, with a long history of use in fermented foods and supplements. However, some may experience mild, temporary side effects like gas or bloating when first introducing it. These symptoms typically subside as the digestive system adjusts.
Certain individuals should use L. casei supplementation with caution or consult a healthcare professional. This applies to those with weakened immune systems (e.g., undergoing chemotherapy or with HIV), due to a small risk of serious infection. Those with damaged heart valves or short bowel syndrome should also seek medical guidance.
L. casei effectiveness varies by strain and dosage. For adults, doses up to 100 billion CFUs daily have been used safely for up to three months; children have used up to 300 million CFUs daily for up to four months. Follow product label directions for storage to maintain viability. Probiotics are not a replacement for medical treatments, and any new or worsening symptoms should prompt a consultation with a healthcare provider.