Bovine colostrum
In athletes, a meta-analysis of 5 trials found 44% fewer days with upper respiratory symptoms on colostrum, from studies with moderate to high risk of bias. Immune markers barely changed. Pooled trials found lower gut permeability. Body composition and performance findings were mixed. Serum IGF-1 rose in two small trials.
- Status
- Dietary supplement in the US.
- Also called
- colostrum, colostrum bovinum, BC, bovine colostrum protein concentrate, first milk
- Taken for
- immunity, colds, gut health, leaky gut, recovery, endurance, lean mass, muscle growth
Strong several reviews agree · Moderate one review or consistent trials · Limited one or a few small studies · Untested no study in people, listed with what it rests on
Shown to help2
What people take it for, and what was found
Shown to help2
Upper respiratory symptoms in athletes
Shown to lower upper respiratory symptom days by about 44% in adults in exercise training, across 5 small trials mostly at risk of bias.
The numbers and sources
- Effect
- Over 8 to 12 weeks, colostrum lowered the incidence rate of upper respiratory symptom days (rate ratio 0.56, 95% CI 0.43 to 0.72) and episodes (0.62, 95% CI 0.40 to 0.99) compared with placebo [1].
- Population
- 5 trials, 152 adults in regular exercise training [1].
- Sources
- [1]
- Caveats
- Four of five studies were judged at moderate or high risk of bias, largely from poor reporting. Most individual studies were not significant on their own [1].
Gut permeability
Shown to lower a urine marker of gut permeability across 10 trials, with very high variation. It cut an exercise-driven rise by 80% in one study.
The numbers and sources
- Effect
- Across 10 trials, colostrum lowered the urinary lactulose to rhamnose ratio (MD -0.24, 95% CI -0.43 to -0.04, I² 99%) and lactulose to mannitol ratio. Plasma I-FABP did not differ [3]. In 12 volunteers, heavy exercise raised permeability 2.5-fold on placebo, and colostrum cut that rise by 80% [4].
- Population
- Healthy athletes and patients [3]; volunteers doing standardized heavy exercise [4].
- Sources
- [3], [4]
- Caveats
- Heterogeneity in the ratio analysis was 99% [3]. Permeability is a surrogate marker, not a measure of illness.
Mixed results1
Lean mass and body composition
Small trials found opposite results: one found 1.5 kg more lean mass over 8 weeks, and another found no change in body composition.
The numbers and sources
- Effect
- In active men and women training for 8 weeks, 20 g a day of colostrum raised bone-free lean mass by 1.49 kg, while the whey protein control group gained 2.11 kg of body weight [5]. In 28 endurance-trained men, 25 g a day for 12 weeks did not change body mass or body composition [6].
- Population
- Active adults [5]; endurance-trained men, crossover [6].
- Sources
- [5], [6]
- Caveats
- Two small trials with opposite findings. The 2001 abstract reports within-group changes rather than a between-group difference [5]. The 12-week trial was funded by the Nutricia Foundation [6].
Not shown to help2
Immune markers
Not shown to change blood or saliva immune markers much in athletes and active adults across 10 trials.
Endurance performance
Small trials found no clear effect on time trials or time to exhaustion, with a 1.9% time-trial gain only after intensive training.
The numbers and sources
- Effect
- In 29 highly trained cyclists, 10 g a day for 10 weeks had an unclear effect on 40 km time-trial performance during normal training, and a 1.9% improvement after 5 days of high-intensity training [7]. In 28 endurance-trained men, 25 g a day raised time to ventilatory threshold but did not change time to exhaustion [6].
- Population
- Trained men [6][7].
- Sources
- [6], [7]
- Caveats
- Small trials. The improvement appeared only after an intensive training block [7].
Doses studied
Trials used 10 g a day for 10 weeks [7], 20 g a day for 8 weeks [5], 25 g a day for 12 weeks [6] and 20 g a day for 2 weeks [8]. The gut permeability study gave colostrum for 14 days before exercise [4].
Risks
Reported risks1
Raised serum IGF-1
Small trials found colostrum raised serum IGF-1 in athletes, while labeled IGF-1 taken by mouth was not absorbed intact.
The numbers and sources
- Effect
- In 9 sprinters and jumpers, 8 days of a colostrum drink raised serum IGF-1 over a whey placebo [9]. In 30 athletes, 20 g a day for 2 weeks raised serum IGF-1 and salivary IgA over maltodextrin. In 12 adults, orally ingested labeled IGF-1 was fragmented in circulation, with no evidence it was absorbed intact [8].
- Population
- Athletes in training [8][9].
- Sources
- [8], [9]
- Caveats
- Small trials of branded products. The trials did not test anti-doping outcomes.
Checked, no increase found1
Use alongside NSAIDs
One small study found colostrum blunted the gut permeability rise from indomethacin in healthy men. Bleeding and ulcers were not measured.
The numbers and sources
- Effect
- In 7 healthy men, indomethacin tripled gut permeability with a whey control, and permeability did not rise significantly when colostrum was taken with it. In 15 patients on long-term NSAIDs, colostrum did not change permeability [10].
- Population
- Healthy volunteers and NSAID users, crossover [10].
- Sources
- [10]
- Caveats
- One small study measuring a surrogate marker. Bleeding and ulcers were not measured.
Claims tested and not found
Sources
- Jones AW, March DS, Curtis F, et al. Bovine colostrum supplementation and upper respiratory symptoms during exercise training: a systematic review and meta-analysis of randomised controlled trials. BMC Sports Science, Medicine and Rehabilitation. 2016. https://doi.org/10.1186/s13102-016-0047-8
- Główka N, Durkalec-Michalski K, Woźniewicz M. Immunological Outcomes of Bovine Colostrum Supplementation in Trained and Physically Active People: A Systematic Review and Meta-Analysis. Nutrients. 2020. https://doi.org/10.3390/nu12041023
- Hajihashemi P, Haghighatdoost F, Kassaian N, et al. Bovine Colostrum in Increased Intestinal Permeability in Healthy Athletes and Patients: A Meta-Analysis of Randomized Clinical Trials. Digestive Diseases and Sciences. 2024. https://doi.org/10.1007/s10620-023-08219-2
- Marchbank T, Davison G, Oakes JR, et al. The nutriceutical bovine colostrum truncates the increase in gut permeability caused by heavy exercise in athletes. American Journal of Physiology-Gastrointestinal and Liver Physiology. 2011. https://doi.org/10.1152/ajpgi.00281.2010
- Antonio J, Sanders MS, Van Gammeren D. The effects of bovine colostrum supplementation on body composition and exercise performance in active men and women. Nutrition. 2001. https://doi.org/10.1016/s0899-9007(00)00552-9
- Durkalec-Michalski K, Główka N, Podgórski T, et al. Twelve-Week Colostrum Bovinum Supplementation Supports Aerobic Capacity but has No Effect on Body Composition in Endurance-Trained Males: A Randomized Placebo-Controlled Crossover Study. European Journal of Sport Science. 2025. https://doi.org/10.1002/ejsc.12288
- Shing CM, Jenkins DG, Stevenson L, et al. The influence of bovine colostrum supplementation on exercise performance in highly trained cyclists. British Journal of Sports Medicine. 2006. https://doi.org/10.1136/bjsm.2006.027946
- Mero A, Kähkönen J, Nykänen T, et al. IGF-I, IgA, and IgG responses to bovine colostrum supplementation during training. Journal of Applied Physiology. 2002. https://doi.org/10.1152/japplphysiol.00002.2002
- Mero A, Miikkulainen H, Riski J, et al. Effects of bovine colostrum supplementation on serum IGF-I, IgG, hormone, and saliva IgA during training. Journal of Applied Physiology. 1997. https://doi.org/10.1152/jappl.1997.83.4.1144
- Playford RJ, MacDonald CE, Calnan DP, et al. Co-administration of the health food supplement, bovine colostrum, reduces the acute non-steroidal anti-inflammatory drug-induced increase in intestinal permeability. Clinical Science. 2001. https://doi.org/10.1042/cs1000627