Benefits
Immune Support
Colostrum contains immunoglobulins and lactoferrin, which may help support immune function. The strongest adult result is a 2023 randomized, triple-blind, placebo-controlled trial in medical university students who took 0.5 to 1.0 grams a day for about 45 days and had fewer days with upper respiratory symptoms, and milder symptoms, than the placebo group. The difference was concentrated in the medical students, who spend the most time around sick patients, rather than in their lower-exposure classmates. A second trial was done in pre-school children, so it does not tell you what to expect as an adult. One caveat belongs with all of it: these low-dose trials come from a single research group testing a single manufacturer's product, with the senior author declaring payment from that manufacturer, and no independent group has repeated them. A pooled analysis of 10 trials in trained adults found little to no change in antibody levels, so the markers do not yet explain the symptom findings.
Gut Health
Colostrum may help support the gut lining. Human trials do exist here, but they are small and they do not agree. Two crossover studies of 12 and 8 people found colostrum blunted the rise in a urinary marker of gut leakiness after hard exercise, and a trial in athletes at about 1 gram a day for 20 days reported lower permeability and lower stool zonulin. A 2024 pooled analysis of 10 trials found an overall reduction in that marker while noting that the trials contradicted one another almost completely and that a blood marker of gut cell damage did not change. The largest single trial, 30 runners on 60 grams a day for eight weeks, found the marker moved the wrong way. The idea that colostrum seals a leaky gut is itself laboratory and animal work, and colostrum is not a treatment for inflammatory bowel disease or any other diagnosed gut condition. The 2020 diarrhea trial treated children who were already ill and under medical care, which is not the same as a healthy adult taking a daily powder.
Athletic Performance and Recovery
Colostrum contains growth factors such as IGF-1, and the theory is that these help muscle repair. Trials measuring strength, power, sprint performance or muscle-damage markers have been small and inconsistent, some reporting modest gains in recovery measures and others finding nothing, and most of the IGF-1 in a swallowed dose is digested before it can act. The better-studied athletic use is the gut rather than the muscle, and even there the results conflict, with the largest and longest trial finding permeability rose on 60 grams a day. Treat colostrum as unproven for performance.
Skin Health
Marketing and social-media claims that colostrum improves skin elasticity or clears acne rest on its growth factors and antioxidants rather than on trials. Oral colostrum has not been shown in human trials to change skin elasticity, acne or wound healing.
Antimicrobial Properties
Lactoferrin and antibodies may act against pathogens. Reports that colostrum reduces infections such as E. coli or H. pylori come from laboratory dishes and animal work, including calf studies using rotavirus, rather than from human trials. The exception is hyperimmune colostrum, a targeted product made by vaccinating the cow against one pathogen, which is a different thing from the standard colostrum sold as a supplement. Colostrum should not be used in place of medical treatment for an infection.
Mechanism of action
Immunoglobulins (IgA, IgG, IgM)
These antibodies neutralize pathogens (bacteria, viruses, fungi) by binding to them, preventing adhesion to mucosal surfaces (e.g., gut lining) and aiding their clearance. IgA, abundant in colostrum, coats intestinal mucosa, enhancing barrier protection. May reduce infections or inflammation, particularly in the gut or respiratory tract.
Lactoferrin
Lactoferrin is an iron-binding protein with antimicrobial properties. It inhibits bacterial growth by sequestering iron, disrupts microbial cell membranes, and modulates immune responses by reducing pro-inflammatory cytokines. These effects come mainly from laboratory studies; the human trials have measured gut permeability rather than gut inflammation directly.
Growth Factors (IGF-1, TGF-α/β)
Stimulate cell proliferation, repair, and regeneration. IGF-1 promotes muscle and tissue growth, while TGF-α/β supports epithelial cell repair, particularly in the gut lining. This is a proposed mechanism from laboratory work. In people, oral colostrum has been tested mainly against markers of gut permeability, with mixed results, and not against tissue healing; most of the IGF-1 in a swallowed dose is digested before it reaches the bloodstream.
Cytokines and Immune Modulators
Regulate immune responses by balancing pro- and anti-inflammatory pathways. They activate immune cells like T-cells and macrophages to fight infections while preventing excessive inflammation. May improve immune resilience, though specific mechanisms in adults are less clear.
Oligosaccharides and Prebiotics
Nourish beneficial gut bacteria, promoting a healthy microbiome. They also bind pathogens, preventing their attachment to intestinal cells. This is a proposed mechanism. No human colostrum trial has measured microbiome composition, and the diarrhea evidence comes from children who were already ill and under medical care.
Clinical trials
Randomized, placebo-controlled trial in pre-school children given bovine colostrum or placebo, looking at upper respiratory tract infection symptoms. (Nutrients, 2023)
Preschool children.
The children given colostrum had fewer and less severe upper respiratory symptoms than those given placebo. This was studied in pre-school children, so it does not show what colostrum does for an adult, and it does not mean colostrum prevents or treats any infection.
A treatment trial published in the Journal of Tropical Pediatrics in 2020, in children who were already ill with acute diarrhea and receiving medical care. They were given bovine colostrum or placebo alongside their usual care.
Children with acute diarrhea.
The children given colostrum had shorter diarrhea and fewer stools than those given placebo, and it was generally well tolerated. This was treatment of a diagnosed illness in children under medical care, not a supplement taken by a healthy adult. Acute diarrhea, especially in a child, needs oral rehydration and a doctor's care, and colostrum is not a substitute for either.
Randomized, triple-blind, placebo-controlled trial in medical university students who took 0.5 to 1.0 grams of bovine colostrum a day, or placebo, for about 45 days. (Baskiewicz-Halasa and colleagues, Nutrients, 2023)
Medical university students, healthy young adults.
Students taking colostrum had fewer days with upper respiratory symptoms, and milder symptoms, than the placebo group. No independent group has repeated it: the same research team, testing the same manufacturer's product and disclosing payment from it, produced the other low-dose colostrum trials as well. It needs replication elsewhere before it can be called settled.