Bovine colostrum
Summary
Bovine colostrum lowered gut permeability markers in a 2024 meta-analysis of 10 trials, but results varied widely and one running trial found the opposite (grade C, mixed). In athletes it cut self-reported respiratory symptoms in one pooled analysis (grade C), while blood immune markers barely changed. Doses ranged from 0.5 to 60 g/day.
Key facts
- Dried first milk from cows, containing immunoglobulins (mainly IgG), lactoferrin and growth factors[6][2]
- Gut permeability markers (C, mixed); self-reported upper respiratory symptoms ↓ (C); serum and saliva antibody levels (little or no effect); performance (D)[1][2][3][4][5][7]
- None set; colostrum is a food product, not an essential nutrient[6]
- 5 graded human outcomes on this page
- October 10, 2026
How it works
ProposedColostrum carries antibodies, lactoferrin and growth factors that in newborn calves support immune defence and gut development. In adults, it is proposed to act locally in the gut lining and mouth, for example by raising salivary IgA, rather than by entering the blood intact. Human trials found little change in blood immune markers, so the mechanism is unconfirmed.[2][6][4]
What the human research says
Human trials only, one row per outcome. The form column shows what each trial actually tested. Grades follow our evidence-grading policy.
At a glance: strongest evidence per outcome
| Outcome | Grade | Effect | Strongest evidence | Rows |
|---|---|---|---|---|
| Immune | Grade C | No effect | Meta-analysis of 10 trials · n = 239 · 2020 | 2 rows |
| Gut | Grade C | Worsened | RCT · n = 30 · 2009 | 2 rows |
| Performance | Grade D | Mixed | RCT · n = 29 · 2026 | 1 row |
Every graded row
| Outcome | Effect | Grade | Best evidence | PMID |
|---|---|---|---|---|
| Blood and saliva immune markers in athletes | No effect | Grade C | Meta-analysis · n = 239 · 2020 10 RCTs in athletes and physically active adults Form: bovine colostrum · Dose: Varied across trials · Duration: Varied across trials No or fairly low effect on serum IgA and IgG, lymphocytes, neutrophils and salivary IgA. | 32276466 (opens PubMed)Source [2] |
| Self-reported upper respiratory symptoms | Improved | Grade C | RCT · n = 174 · 2003 Adult men in earlier double-blind exercise trials Form: concentrated bovine colostrum protein · Dose: 60 g/day · Duration: 8 weeks 32% on colostrum reported respiratory symptoms in weeks 2–8 vs 48% on whey; symptom duration did not differ. | 12923655 (opens PubMed)Source [4] |
| Intestinal permeability during running training | Worsened | Grade C | RCT · n = 30 · 2009 Healthy adult men running 3 times a week Form: bovine colostrum · Dose: 60 g/day · Duration: 8 weeks The lactulose/rhamnose ratio rose 251% with colostrum vs 21% with whey and −7% in controls, meaning gut permeability increased. | 22253980 (opens PubMed)Source [5] |
| Intestinal permeability in athletes at peak training | Improved | Grade C | RCT · n = 16 · 2017 Athletes during peak competition training Form: bovine colostrum · Dose: 500 mg/day · Duration: 20 days Lactulose/mannitol test values fell into the normal range and dropped more than with whey placebo; stool zonulin fell more too. | 28397754 (opens PubMed)Source [3] |
| Strength, power and body composition | Mixed | Grade D | RCT · n = 29 · 2026 Club-level rugby players during the season Form: bovine colostrum vs soy protein · Dose: 38 g/day · Duration: 8 weeks Vertical jump rose 1.0 cm vs −0.5 cm on soy; bench and leg press strength, aerobic power, body composition, immune markers and illness rates did not differ. | 40640599 (opens PubMed)Source [7] |
Forms
| Form | Elemental % | Absorption (human data) | GI tolerance | Studied for |
|---|---|---|---|---|
| Bovine colostrum powder or capsules | Varies[6] | Large proteins such as immunoglobulins are thought to act mainly in the gut rather than being absorbed intact; no human absorption data in our sources.[6] | Generally well tolerated across trials summarized in a systematic review.[6] | Gut permeability, respiratory symptoms, performance |
| Concentrated colostrum protein | Varies[4] | No human absorption data in our sources.[4] | Used at 60 g/day for 8 weeks in exercise trials.[4] | Respiratory symptoms in athletes |
Studied doses
Doses studied in human trials ranged from 0.5 g/day to 60 g/day of bovine colostrum, for 20 days to 8 weeks. Lower doses (0.5–1 g/day) appear in gut and student trials; 20–60 g/day in athlete trials.[3][4][5][7]
Interactions
Published interactions only: each row cites a source. No row means none was found in our sources, not that a combination is safe.
None found in our sources.
Who should be careful
- Milk allergy
- Colostrum is cow's milk. People with cow's milk protein allergy should avoid it.[6]
- Medicines
- No published drug interactions for bovine colostrum were found in our sources. That is an absence of data, not proof of safety with every medicine.[1][6]
- Children and older adults
- A systematic review found conflicting results in children and little evidence in older adults.[6]
- High doses and gut permeability
- One trial at 60 g/day during running training found gut permeability increased rather than decreased.[5]
Talk to your pharmacist or clinician before starting a supplement, especially if you take prescription medicines.
How to read the label
- Label dose vs clinical doseGut and student trials used 0.5–1 g/day, but most athlete trials used 20–60 g/day, which is tens of grams of powder.[3][4][7]
- Check the immunoglobulin (IgG) contentTrials used different products and concentrations (the respiratory analysis used a concentrated colostrum protein), so a gram of one is not equal to a gram of another.[6]
- Dairy is the base ingredientColostrum is a milk product, so check the label for allergen statements.[6]
Cost per studied dose, without the sales pitch
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Cost per studied dose
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Frequently asked questions
Does colostrum help leaky gut?
A 2024 meta-analysis of 10 trials found lower gut permeability test results with colostrum, but results varied a lot, and one 60 g/day running trial found permeability went up. The evidence is mixed.[1][5]
Does colostrum boost the immune system?
A meta-analysis of 10 athlete trials found little or no change in blood or saliva antibody levels. One pooled analysis found fewer self-reported colds over 7 weeks at 60 g/day.[2][4]
How much colostrum was used in studies?
From 0.5 g/day to 60 g/day, for 20 days to 8 weeks.[3][4][5][7]
Is colostrum safe?
Trials report it is generally well tolerated. It is a cow's milk product, so it is not suitable for people with milk allergy.[6]
Does colostrum improve athletic performance?
Little evidence. In rugby players, 38 g/day for 8 weeks improved vertical jump slightly but not strength, aerobic fitness or body composition, compared with soy protein.[7]
Sources
- [1]Bovine Colostrum in Increased Intestinal Permeability in Healthy Athletes and Patients: A Meta-Analysis of Randomized Clinical Trials.. Dig Dis Sci, 2024. meta-analysis
- [2]Immunological Outcomes of Bovine Colostrum Supplementation in Trained and Physically Active People: A Systematic Review and Meta-Analysis.. Nutrients, 2020. meta-analysis
- [3]Oral Supplementation with Bovine Colostrum Decreases Intestinal Permeability and Stool Concentrations of Zonulin in Athletes.. Nutrients, 2017. RCT
- [4]Concentrated bovine colostrum protein supplementation reduces the incidence of self-reported symptoms of upper respiratory tract infection in adult males.. Eur J Nutr, 2003. RCT
- [5]Bovine colostrum supplementation during running training increases intestinal permeability.. Nutrients, 2009. RCT
- [6]Bovine Colostrum Applications in Sick and Healthy People: A Systematic Review.. Nutrients, 2021. systematic-review
- [7]Bovine colostrum supplementation in rugby.. Eur J Appl Physiol, 2026. RCT
What changed
- First draft. Every PMID checked against NCBI E-utilities esummary (title and year taken from the record) and abstracts read for the cited rows.
- Adversarial review pass: every claim re-checked against the cited abstract (or full text where noted), PMIDs re-verified via NCBI esummary, unsupported label-market statements removed, two evidence rows with unreported pooled n removed. Page set indexable.