Lactobacillus rhamnosus GG (LGG) is a specific type of bacterium that naturally resides in the human intestines. It is classified as a probiotic, which refers to live microorganisms that, when administered in adequate amounts, can offer a health benefit to the host. As one of the most widely researched probiotic strains globally, its scientific designation “GG” is derived from the surnames of the two scientists, Sherwood Gorbach and Barry Goldin, who first isolated it.
Health Applications of LGG
Lactobacillus rhamnosus GG is recognized for its positive effects on digestive health, particularly against diarrhea. Research found that supplementing with LGG lowered the risk of diarrhea associated with antibiotic use. Antibiotics can disturb the natural balance of gut microorganisms, and taking LGG may help restore this balance. It is also used to manage diarrhea from rotavirus in infants and children and may help prevent traveler’s diarrhea.
Beyond the digestive tract, LGG interacts with and supports the body’s immune system. Its use has been linked to a reduced risk of certain common infections, and some studies suggest it may lower the incidence of lung infections in children in daycare settings. The probiotic may also improve the immune response to vaccines, indicating its influence extends beyond the gut.
Researchers have explored the effects of LGG on skin health, particularly in pediatric populations with atopic dermatitis, a type of eczema. While more investigation is needed, some studies have pointed to a potential benefit. The connection is related to the “gut-skin axis,” a concept suggesting that gastrointestinal health can influence skin conditions.
How LGG Works in the Body
One of the primary mechanisms behind LGG’s effectiveness is its capacity to adhere to the intestinal lining. This strain possesses hair-like appendages known as pili, which allow it to stick to the cells of the gut wall. This adhesion helps the probiotic to colonize the gastrointestinal tract and persist longer. By doing so, it helps to fortify the natural barrier of the gut, which is composed of cells linked by structures called tight junctions. A stronger gut barrier can prevent unwanted substances from leaking from the intestine into the bloodstream.
Once established in the gut, LGG engages in a process known as competitive exclusion. It competes with potentially harmful bacteria for physical space on the intestinal wall and for essential nutrients. By consuming resources and occupying attachment sites, LGG makes it more difficult for pathogenic organisms to thrive. LGG also produces substances like lactic acid, which creates a more acidic environment less hospitable to many harmful bacteria.
LGG also actively communicates with the body’s immune system. A large portion of the immune system is located within the gut, and LGG can interact with these immune cells. This interaction helps to modulate the immune response, preventing it from overreacting or underreacting. For instance, bacteria can bind to proteins on immune cells, which in turn activates the immune system. This modulation is a reason why LGG is studied for its effects on both local gut inflammation and systemic immune functions.
Sources and Recommended Intake
Lactobacillus rhamnosus GG is not typically found naturally in most common fermented foods; instead, it is specifically added to certain products during manufacturing. Consumers can find it in a variety of fortified dairy items, such as specific brands of yogurt, kefir, and milk. It is important to read product labels carefully, as only some will contain this exact strain, and the packaging should explicitly state its presence.
The most common way to consume LGG is through dietary supplements, which offer a more concentrated dose. These supplements are available in several convenient forms, including capsules, chewable tablets, powders, and liquid drops designed for infants. This variety allows for easier administration across different age groups and preferences.
The quantity of probiotics in a product is measured in Colony-Forming Units (CFUs), which indicates the number of viable bacteria. Dosages of LGG used in scientific studies vary widely depending on the health condition being examined, but often range from 1 billion to 20 billion CFUs per day. For specific guidance, follow the dosage instructions on the supplement’s label or consult with a healthcare professional.
Safety and Potential Side Effects
Lactobacillus rhamnosus GG is widely considered safe for consumption by the general public and has a long history of use in foods and supplements. It is generally recognized as safe (GRAS) by regulatory bodies for healthy adults, children, and infants. Most individuals who take LGG do not experience any adverse effects.
When side effects do occur, they are typically mild and short-lived, related to the digestive system adjusting to the new microorganisms. The most commonly reported issues are temporary increases in gas or bloating. These symptoms usually resolve on their own as the body adapts.
Despite its excellent safety record, certain individuals should exercise caution and speak with a doctor before using LGG supplements. This includes people who are severely immunocompromised, such as those with certain medical conditions or undergoing treatments that suppress the immune system. Critically ill patients in a hospital setting should also avoid probiotics unless directed by their medical team, to avoid the rare risk of infection.