Colostrum

Colostrum

Identity and Natural Source

Colostrum — also called "first milk," "early milk," or beestings — is the pre-milk secretion produced by the mammary glands of mammals during the perinatal period. As a secretion of the mammary gland, it is produced and accumulated in the final stage of pregnancy and in the first days after parturition. In commercial supplement contexts, supplemental forms of colostrum are from bovine sources, meaning they are produced by cows shortly after they give birth.

Known as the "first milk" or the "first food," bovine colostrum (BC) is produced by healthy mammary glands up until the first 72 hours after delivery. While similar in composition to human colostrum, bovine colostrum contains a different profile of antibodies and growth factors tailored to the needs of newborn calves.

The substance has accumulated several informal designations in the scientific and trade literature. Due to the importance of colostrum, it is occasionally also referred to as "Liquid Gold." In trade and regulatory contexts, it is known by a range of common names, including BCC (bovine colostrum concentrate), bovine colostrum, cow milk colostrum, early milk, hyperimmune milk, immune milk, Lactobin, and lactoferrin.

Common Forms and Preparations

Bovine colostrum for human consumption is collected and frozen on individual farms and thereafter shipped frozen to processing facilities, where it is pasteurized and further treated through optional fat and lactose removal before spray- or freeze-drying to powder. Available colostrum products include raw whole colostrum powder, raw skim colostrum powder, and industrially produced colostrum milk protein concentrate. Currently, bovine colostrum is available in liquid form or as spray- or freeze-dried colostrum powder. The powder can also be marketed as a dietary supplement in the form of sachets, capsules, or chewable tablets.

The drying method has consequences for bioactivity. Freeze-dried samples contain higher levels of protein and defensive proteins (IgG and IgA) compared to spray-dried samples. The use of spray drying is limited, as it may cause heat-induced damage to colostrum proteins, causing disruption of key bioactive proteins such as lactoferrin and a loss in immunoglobulins. Pasteurization caused a 33% decrease in IGF-1, while a further 30% reduction was observed in freeze-drying, indicating that the bioactive components of bovine colostrum decrease gradually by filtration, heat treatment, and freeze-drying processes.

Historically, liquid fresh colostrum was primarily consumed, but pasteurized colostrum is also commercially available as a standalone drink, though production remains small. In European cultures and elsewhere such as India and Scandinavia, colostrum is also used in the production of cheeses and other traditional foods.

A specialized commercial category, known as hyperimmune bovine colostrum (HBC), is produced by vaccinating pregnant cows against specific pathogens so that the resulting colostrum contains elevated targeted antibody titers. BC is homologous to human colostrum, although immune factors are present in greater concentrations. This hyperimmune BC, rich in targeted IgG, is different from conventional antimicrobials as it does not disturb the integrity of the gut microflora, nor will it potentially lead to the emergence of new antibiotic-resistant organisms.

Standardization of commercial bovine colostrum products is difficult because antibody content varies widely. The concentration of the above-mentioned compounds is variable and depends on many factors, including breed, productivity, parity, feeding intensity, season of the year, and/or production system.

Traditional and Historical Use

Ayurvedic and Indian Traditions

The use of colostrum for both medicinal and spiritual purposes has been documented in traditional Ayurvedic medicine and among the ancient Hindu rishis (spiritual leaders) of India. Bovine colostrum is well known for its medicinal properties from ancient cultures. Historically in India, the colostrum is used in both medical and spiritual terms since ancient times.

Scandinavia and European Traditions

In European cultures and elsewhere such as India and Scandinavia, colostrum is also used in the production of cheeses and other traditional foods. In Scandinavian countries, traditional colostrum-based puddings and dishes have historically been prepared from the surplus first milk of dairy cows.

Pre-Antibiotic Medical Use

At the turn of the 20th century, the use of colostrum was advocated to protect infants against both human and bovine infections. Prior to the advent of sulfa drugs and other antibiotics, colostrum was used to boost defense against immune diseases. Albert Sabin isolated anti-polio antibodies in bovine colostrum in the 1950s; the first experiments with hyperimmune colostrum were conducted in the 1960s.

Modern Supplement Era

More recently, dried colostrum is collected and processed as a dietary supplement, which is widely consumed for perceived health benefits. In the US and EU, colostrum supplements are marketed for a variety of health benefits, including boosting immunity and gastrointestinal (GI) health.

Key Constituents and Active Compounds

Overview of Composition

Colostrum's composition closely resembles that of blood and differs markedly from milk. It contains a range of nutrients, including biologically active compounds and proteins, lipids, lactose, and vital fatty acids. Compared to mature dairy milk, bovine colostrum contains around double the total solids, double the fat content, approximately five-fold the protein content, and significantly higher content of most micronutrients.

Immunoglobulins

The immunoactive substances with immune activity in BC are mainly immunoglobulins (Ig), which are very abundant. Ig and antibacterial components such as lactoferrin, cytokines, lactoperoxidase, and lysozyme play a very important role in the body's immunity.

Bovine colostrum contains between 50-fold and 300-fold higher concentrations of immunoglobulins (IgG, IgA, IgM), up to 250-fold higher concentrations of lactoferrin, and up to double the content of other antimicrobial proteins and peptides (such as lactoperoxidase and lysozyme) compared to mature dairy milk.

Colostrum initially contains approximately 90 mg/mL IgG1, 2.8 mg/mL IgG2, 1.6 mg/mL IgA, and 4.5 mg/mL IgM; these concentrations decline by 92%, 87%, 93%, and 84% respectively in samples collected later. The IgG concentration in BC is nearly 100 times higher than in human colostrum, thus providing better passive immunity and enhanced antimicrobial defense.

Growth Factors

The major bioactive components of bovine colostrum include immunoglobulin G (IgG), lactoferrin (LF), growth factors (IGF-I, TGF-β, EGF), oligosaccharides, and bioactive peptides. Growth factors — including insulin-like growth factor (IGF), epidermal growth factor (EGF), transforming growth factor (TGF), platelet-derived growth factor (PDGF), and vascular endothelial growth factor (VEGF) — regulate the growth, maturation, and function of various tissues, such as bone, muscle, connective tissue, nerve tissue, skin, and especially the gastrointestinal mucosa.

Colostrum initially contains 289–310 ng/mL TGF-β2, which diminishes to 66 ng/mL over time. The content of IGF-1 postpartum decreases from 870 to 150 ng/mL. Within the first 10 hours after birth, colostrum contains the optimal concentration of growth factors, although this timeframe may vary depending on the source and environmental factors.

Lactoferrin

Lactoferrin is a glycoprotein with antibacterial as well as antiviral, lipopolysaccharide-binding, and growth-regulating effects. It is present in bovine colostrum at concentrations far exceeding those found in mature bovine milk.

Antimicrobial Enzymes

Lactoperoxidase is an antibacterial enzyme that inhibits bacterial metabolism and has been shown to be toxic to a range of gram-positive and gram-negative bacteria. It also possesses antiviral activities.

Other Components

Colostrum contains relatively low concentrations of lactose, indicating its primary functions are immunologic and trophic rather than nutritional. Levels of sodium, chloride, and magnesium are higher, and levels of potassium and calcium are lower in colostrum than in later milk.

Colostrum also contains heat shock protein 70 (Hsp70), which has a protective function for cells, specifically protecting the integrity of cell membranes under stress conditions.

Approximately 50 polypeptides are present in BC as growth factors. In addition, proline-rich polypeptides (PRPs) have been identified as contributors to immunomodulatory effects, though investigation into their precise mechanisms continues.

Mechanisms of Action

Mucosal Immune Defense

The major bioactive components of bovine colostrum play a role in epithelial repair, suppression of inflammation, balancing the microbiota, and enhancing the mucosal barrier. The intestinal sealing capacity of BC has also been attributed to BC-mediated induction of the intestinal barrier-strengthening cytokine TGF-β.

Growth Factor Signaling

IGFs stimulate epithelial cell migration and proliferation, which improves re-epithelialization, an essential stage of the healing process that replaces the skin's or mucosal protective layer over a wound site. TGF-β is a key growth factor involved in the regulation and repair of the GI tract and has a variety of biological functions, including oncogenesis suppression, suppression of immune responses, and cell proliferation.

Systemic IGF-1 — An Important Clarification

Early suggestions that supplementation with bovine colostrum products could increase systemic IGF-1 levels are not supported by the balance of available evidence examining a range of doses over both short- and long-term periods.

Scientific Evidence by Area of Use

1. Gastrointestinal Health and Intestinal Permeability

Various animal models and recent human studies show that bovine colostrum has various positive effects against gastrointestinal tract diseases such as inflammatory bowel disease (IBD), irritable bowel syndrome (IBS), NSAID-induced enteropathy, and necrotizing enterocolitis (NEC). These effects include preservation of epithelial integrity, reduction of inflammatory markers, and improvement of intestinal permeability.

A systematic review and meta-analysis published in PubMed found that vigorous exercise profoundly increases intestinal permeability, and BC supplementation helps to reverse gut permeability in athletes. BC supplementation may be highly beneficial in improving gut permeability in athletes.

A systematic review of studies evaluating standard bovine colostrum oral supplementation identified 51 studies (N=2,326, with study sizes ranging from 3 to 605 patients); only 2 studies were of high quality. Data from the only 2 studies (n=7 and n=15) evaluating use in NSAID-induced GI injury showed evidence of possible benefit and protection of gut permeability; however, the studies were small and of short duration.

Use as a food supplement showed interesting effects in reducing intestinal permeability in healthy and sick subjects. Overall, evidence for gut permeability is among the more robust findings in the BC clinical literature, though studies tend to be small and heterogeneous.

2. Infectious Diarrhea

BC shows promise for the treatment and/or prevention of infectious diarrhea in adults and children. Several human studies in children and adults, usually performed in low-income countries, suggest that the use of hyperimmunized BC against specific pathogens has value in reducing diarrhea. A smaller number of studies has shown positive effects when using non-hyperimmunized BC, especially against rotavirus and E. coli-induced diarrhea.

A meta-analysis published in Scientific Reports (2019) searched PubMed, Cochrane Library, and ClinicalTrials.gov and included five RCTs (N=324 children). Under pooled analysis, bovine colostrum consumption correlated with a significant reduction in stool frequency of infectious diarrhea, by 1.42 times per day (95% CI: −2.70, −0.14).

A systematic review of clinical trials on GI diseases published in Systematic Reviews (Springer, 2024) enrolled 22 clinical trials with 1,427 patients. Diarrhea, the most frequently evaluated symptom (20 interventional arms), was decreased in frequency with BC supplementation in 15 of these arms. However, there was debate about the effect of BC on GI symptoms based on BC dosage and duration of consumption.

Evidence for HBC against H. pylori is mixed. HBC also had a beneficial effect on rotavirus but not on H. pylori infection. In vitro data and animal models are more consistently positive than human trial data for this indication.

3. HIV-Associated Diarrhea

Bovine colostrum may have a role in the management of HIV-associated diarrhea. More recently, bovine colostrum was well-tolerated in HIV-infected persons for the treatment of HIV-associated diarrhea. Early trials from the 1990s investigating immunoglobulin concentrates from bovine colostrum in HIV-positive patients with chronic diarrhea demonstrated some clinical benefit, though study sizes were small and further controlled research in this area is limited.

4. Upper Respiratory Tract Infections (URTI)

A systematic review and meta-analysis of RCTs (Jones et al., 2016, BMC Sports Science, Medicine and Rehabilitation) identified five trials involving 152 participants, all involved in regular exercise training. Over an 8–12 week follow-up period, bovine colostrum supplementation compared to placebo significantly reduced the incidence rate of URS days (rate ratio 0.56, 95% CI 0.43 to 0.72, P < 0.001) and URS episodes (0.62, 0.40 to 0.99, P = 0.04) by 44% and 38% respectively.

A broader systematic review of 10 studies found some support for BC for preventing URTI; however, caution is warranted in interpreting the results because statistical significance was only found in pooled self-reported data. Additionally, heterogeneity was found in study populations, dosages, formulations, quality of methodologies, and results.

Use as a food supplement showed interesting effects in preventing upper respiratory illness in sportsmen. The evidence is most consistent within exercising populations and during periods of intensified training; extrapolation to the general non-athlete population is premature.

5. Athletic Performance, Body Composition, and Recovery

Studies have investigated the effects on body composition, physical performance, recovery, gut damage and permeability, immune function, and illness risk. Although some studies have shown protection against performance decrements caused by periods of intensified training, there is limited evidence for effects on body composition and physical performance. There is stronger evidence for benefit on gut permeability and damage markers and on immune function and illness risk, especially during periods of intensified training.

There is some evidence from well-conducted placebo-controlled experimental trials that bovine colostrum supplementation may be beneficial to endurance performance, especially during periods of intensified training. However, overall results across trials are inconsistent. Bovine IGF-I is structurally identical to human proteins, and short-term studies have been conducted in both high-performance (elite) athletes and other athletes by a limited pool of researchers. Findings from these studies are inconsistent, with some, but not all, showing enhanced performance and changes in body composition.

One randomized crossover placebo-controlled study examined the effects of a 12-week supplementation protocol in endurance athletes. Each athlete was supplemented with a chronic (12-week) dose of 25 g/day of bovine colostrum and placebo treatment in a randomized crossover sequence.

6. Immunological Outcomes in Physically Active Individuals

A 2020 systematic review and meta-analysis published in Nutrients analysed data from 10 RCTs involving 239 participants. There is currently only one systematic review and meta-analysis of five RCTs showing that oral supplementation of BC can reduce the incidence rate of URTI days and episodes in athletes. In terms of immunological biomarkers, studies are inconclusive. These results suggest that a period of supplementation longer than 4 weeks and/or higher doses of BC split throughout the day may be necessary to induce significant changes in salivary IgA production. It may also be possible that the effect of BC is not universal across athletes in different sports and in different age groups.

7. Pediatric Use

Conflicting results have been provided in the pediatric population, and little evidence is available on its use in older adults. There are many reports that the use of bovine colostrum as a breast milk fortifier for preterm infants provides necessary immune support for premature infants, but the selection of bovine colostrum products must be free of Bacillus cereus because this organism is very dangerous for premature infants.

8. Other Investigated Areas

BC supplements are promoted for prevention and management of neurological disorders (dementia, cognition, Parkinson's disease, and Alzheimer's disease), cardiovascular diseases, immunity-related and allergy problems, skin disorders, inflammatory bowel disease, gut microbial symbiosis, type-2 diabetes, and improved athletic performance. However, for most of these indications, clinical evidence in humans is limited, preliminary, or absent, and claims rest largely on in vitro or animal model data.

There is increasing evidence of efficacy in boosting the immune system, preventing upper respiratory tract infection, reducing GI permeability, and enhancing athletic performance, although data are conflicting and are based on small sample sizes and studies of limited quality.

Body Systems Associated with Colostrum

• Gastrointestinal system: intestinal barrier integrity, reduction of permeability, management of infectious diarrhea, IBD, IBS, NSAID-induced enteropathy
• Immune system: passive immunity transfer (IgG-mediated), modulation of salivary IgA, reduction of URTI incidence
• Musculoskeletal system: tissue repair via IGF-1 and EGF, potential support for muscle recovery in athletes
• Endocrine/metabolic: IGF-1 signaling (though systemic elevation not confirmed by oral supplementation)
• Antimicrobial defense: lactoferrin- and lactoperoxidase-mediated protection against bacterial and viral pathogens

Dosage Forms and Dosages Reported in Studies

Dosages up to 60 g/day for up to 12 weeks have been used in clinical trials evaluating use for athletic enhancement. In trials using bovine colostrum for exercise-induced GI permeability, dosages of 20 g/day for 14 days, or 1 g/day for 20 days have been used; in one trial, a dosage of 1.7 g/kg/day for 7 days prior to an exercise protocol was used.

As only 2 doses were used (20 g and 60 g/day) in one study, this is not a dose–response study per se, but it does suggest that there is little value to be gained from doses in excess of 20 g/day in the context of that study. Further research is required, with a full range of doses up to 20 g/day (dose–response) to determine the optimal dose, although this is likely to vary between individuals and even within individuals under different conditions.

In one 12-week crossover study in endurance athletes, each athlete was supplemented with 25 g/day of bovine colostrum, provided in powder form taken twice a day (12.5 g in the morning and 12.5 g in the afternoon).

While the typical dose in some contexts is 10 g/day, doses as high as 10 g four times daily have been studied.

No universally established clinical dose exists; the appropriate dose varies by indication, population, and the bioactivity of the specific product used.

Safety Considerations and Interactions

General Tolerability

Based on the current literature, BC supplementation is considered to be well tolerated and safe for the human population. Reported adverse effects include only mild complaints, like nausea, diarrhea, flatulence, unpleasant taste, and abdominal discomfort, which may disappear with time.

Adverse reactions have been few in number and slight in severity. In most clinical studies on the efficacy of bovine colostrum there have been no demonstrable adverse effects. When they have occurred, they have mostly consisted of nausea, emesis, flatulence, and mild diarrhea.

The US Food and Drug Administration (FDA) has accepted the safety of hyperimmune milks on the basis that no adverse health effects have been shown in clinical studies.

Allergy and Intolerance

While BC products are well tolerated, some patients allergic to dairy products may experience undesirable side effects such as gastrointestinal problems like flatulence and nausea. Colostrum administration should be avoided in persons allergic to cow's milk. In addition, lactose intolerance in people, β-lactoglobulin allergy, and many other factors mean that bovine colostrum cannot completely replace human colostrum or cow's milk.

Pregnancy and Lactation

Information regarding safety and efficacy in pregnancy and lactation is lacking.

WADA and Anti-Doping Considerations

In 2013, the World Anti-Doping Agency (WADA) first published a statement that bovine colostrum contains 'high' levels of IGF-1 and other growth factors which could influence the outcome of a doping test, and for this reason they do not recommend its consumption.

However, this position has been challenged by research. Early suggestions that supplementation with bovine colostrum products could increase systemic IGF-1 levels are not supported by the balance of available evidence examining a range of doses over both short- and long-term periods. Being a dietary supplement and without any narcotic, steroidal, or euphorigenic properties, it has been suggested that BC should be removed from the WADA anti-doping list.

Product Quality and Microbial Safety

Since bovine colostrum is a food rather than a drug, its adverse effects may be minimal, provided the product is obtained from a reliable source and is prepared using good manufacturing practices. For bovine colostrum used in preterm infants, products must be free of Bacillus cereus, as this organism is very dangerous for premature infants.

Hepatic Enzyme Elevation (Isolated Report)

In one study, transient moderate elevations in serum levels of hepatic transaminases were observed in volunteers who received bovine immunoglobulin concentrates prepared against E. coli (5/10) and rotavirus (2/10). This effect was attributed to diets high in protein provided at the hospital.

Drug Interactions

No drug interactions are well documented. Contraindications other than milk allergy have not been identified.

Standardization Limitation

The lack of standardization of products reduces the external validity of clinical trial data; results indicating efficacy of a particular colostrum product cannot be generalized to apply to other products.

Evidence Summary

The overall evidence base for bovine colostrum as a human dietary supplement is developing but uneven across applications. While not specifically designed to support human life, bovine colostrum is nutrient-rich and appears to be safe for human consumption. Whether it has health benefits for humans is less certain.

• Strongest evidence: Reduction of gut permeability in athletes during intensified training; reduction of upper respiratory illness days/episodes in exercising adults (multiple RCTs, systematic review and meta-analysis)
• Moderate/mixed evidence: Reduction of stool frequency in childhood infectious diarrhea (meta-analysis of 5 RCTs); management of HIV-associated diarrhea (early clinical data, limited size)
• Weak or preliminary evidence: Athletic performance enhancement; body composition; IBD; neurological disorders; type-2 diabetes; skin health (mostly animal/in vitro data or very small, low-quality trials)

Well-designed, randomized, and placebo-controlled clinical trials are needed to assess the therapeutic potential, long-term safety, and efficacy as well as optimal dose levels of colostrum products in athletes and physically active men and women.

References

• Frontiers in Immunology (2024) — Exploring the impact of colostrum supplementation on athletes: a comprehensive analysis of clinical trials and diverse properties (PMC11116638)
• Nutrients (2020) — Composition and Factors Affecting Quality of Bovine Colostrum: A Review (PMC6940821)
• Mayo Clinic Press (2025) — Colostrum: Super supplement or overhyped?
• PMC (2024) — Revealing the Potency of Growth Factors in Bovine Colostrum (PMC11279796)
• Frontiers in Nutrition (2022) — Bioactive compounds, nutritional profile and health benefits of colostrum: a review (PMC9592540)
• Frontiers in Nutrition (2021) — Bovine Colostrum and Its Potential for Human Health and Nutrition
• Drugs.com Natural Product monograph — Bovine Colostrum Uses, Benefits & Dosage (reviewed December 2025)
• PMC (2024) — A Review: The Effect of Bovine Colostrum on Immunity in People of All Ages (PMC11242949)
• PMC (2025) — Clinical Applications of Bovine Colostrum in Gastrointestinal Disorders: Mechanisms, Evidence, and Therapeutic Potential (PMC12608013)
• PMC (2023) — Colostrum and Lactoferrin Protect against Side Effects of Therapy with Antibiotics, Anti-inflammatory Drugs and Steroids, and Psychophysical Stress (PMC10136316)
• PMC (2021) — The Use of Bovine Colostrum in Sport and Exercise (PMC8225123)
• PMC (2021) — Bovine Colostrum Applications in Sick and Healthy People: A Systematic Review (PMC8308243)
• PubMed (2024) — Bovine Colostrum in Increased Intestinal Permeability in Healthy Athletes and Patients: A Meta-Analysis of Randomized Clinical Trials
• PMC (2016) — Bovine colostrum supplementation and upper respiratory symptoms during exercise training: a systematic review and meta-analysis of randomised controlled trials (PMC4960812)
• PMC (2020) — Immunological Outcomes of Bovine Colostrum Supplementation in Trained and Physically Active People: A Systematic Review and Meta-Analysis (PMC7231218)
• PMC (2024) — The effect of 12-week high-dose Colostrum Bovinum supplementation on immunological, hematological and biochemical markers in endurance athletes (PMC11532120)
• PMC (2022) — A Systematic Review of the Influence of Bovine Colostrum Supplementation on Leaky Gut Syndrome in Athletes (PMC9227274)
• PMC (2017) — Effects of bovine colostrum on recurrent respiratory tract infections and diarrhea in children (PMC5402550)
• PMC / Scientific Reports (2019) — Bovine colostrum and product intervention associated with relief of childhood infectious diarrhea (PMC6395637)
• PMC (2024) — Therapeutics effects of bovine colostrum applications on gastrointestinal diseases: a systematic review (PMC10898101)
• PMC (2022) — The Use of Bovine Colostrum in Medical Practice and Human Health: Current Evidence and Areas Requiring Further Examination (PMC8746576)
• ScienceDirect (2002) — Immunoglobulins, growth factors and growth hormone in bovine colostrum and the effects of processing
• MDPI Foods (2021) — Bovine Colostrum for Human Consumption — Improving Microbial Quality and Maintaining Bioactive Characteristics through Processing
• PMC (2022) — Production of Bovine Colostrum for Human Consumption to Improve Health (PMC8762312)
• PMC (2020) — Oral bovine colostrum supplementation does not increase circulating insulin-like growth factor-1 concentration in healthy adults (PMC7230051)
• Food Science of Animal Resources / Springer (2026) — Health benefits and value addition of bovine colostrum: a comprehensive review
• Systematic Reviews / Springer (2024) — Therapeutics effects of bovine colostrum applications on gastrointestinal diseases: a systematic review
• ScienceDirect (2021) — Bovine colostrum: A source of bioactive compounds for prevention and treatment of gastrointestinal disorders
• PMC (2025) — Exploring the Therapeutic Potential of Bovine Colostrum for Cancer Therapies (PMC12386378)
• International Journal of Food Properties (2024) — In vitro evaluation of spray and freeze-dried bovine colostrum powder and their effects on nutritional and functional properties
• Journal of Dairy Research / Cambridge (2022) — A review of bovine colostrum preservation techniques
• ClinicalTrials.gov — Bovine Colostrum for Patients With Non-Alcoholic Fatty Liver Disease (NCT01016418)
• Cleveland Clinic Health (2024) — Bovine Colostrum: Benefits and Side Effects