Colostrum

Colostrum is a pre-milk fluid produced in the mammary glands of mammals that have recently given birth. Newborns have immature digestive and immune systems, so the enzymes, antibodies, and growth factors colostrum provides promote growth and fight disease. Though colostrum is produced by all mammals, colostrum supplements are usually derived from bovine or (less frequently) goat sources. Colostrum has become a popular nutritional supplement because it is a rich source of enzymes, antibodies, and growth factors not found in other dairy products.

The undeveloped intestinal tract of a newborn allows the growth factors present in colostrum to pass freely through the intestinal wall for absorption. However, fully-developed adult mammal intestines will break down the beneficial compounds before they can be absorbed into the blood stream. Though digestive enzymes prevent colostrum growth factors from affecting muscles, they will still exert a local effect, which increase intestinal integrity. This prevents inflammation, like the kind that can be caused by prolonged, intense exercise, like competitive cycling. Outside of intense exercise, supplementing colostrum will have an effect similar to supplementing whey protein or casein protein.

Athletes often supplement colostrum in an effort to increase fat burning, add lean mass, or increase strength. Since their digestive systems are fully developed, these effects do not occur, and the body breaks down the growth factors and enzymes that colostrum provides before they can be transported to muscle cells.

The antibodies present in colostrum are also effective at reducing diarrhea caused by Escherichia coli and reducing the risk of HIV infection. To prevent E. coli-induced diarrhea, the colostrum must be obtained from an immunized animal.

The standard colostrum dose intended as a protein supplemented or intestinal health agent is between 20-60g. This dose contains 2-4g (10-20%) of immunoglobulin.

Colostrum is supplemented through a powder form.

A colostrum dose intended to reduce the risk of E. coli-induced diarrhea should contain between 400-3,500mg of immunoglobulins. It should be taken shortly after a meal. Colostrum intended to reduce the risk of diseases related to E. coli must come from a cow (or similar animal) that has been immunized against E. coli.

The Human Effect Matrix looks at human studies (it excludes animal and in vitro studies) to tell you what effects colostrum has on your body, and how strong these effects are.

Grade	Level of Evidence [show legend]
	Robust research conducted with repeated double-blind clinical trials
	Multiple studies where at least two are double-blind and placebo controlled
	Single double-blind study or multiple cohort studies
	Uncontrolled or observational studies only

Level of Evidence ? The amount of high quality evidence. The more evidence, the more we can trust the results.	Outcome	Magnitude of effect ? The direction and size of the supplement's impact on each outcome. Some supplements can have an increasing effect, others have a decreasing effect, and others have no effect.	Consistency of research results ? Scientific research does not always agree. HIGH or VERY HIGH means that most of the scientific research agrees.	Notes
	Weight	-	High See all 13 studies	The majority of studies fail to find any significant influence of colostrum on body weight that is atypical of protein sources, although as it confers protein and calories it remains possible to gain weight from colostrum.
	Diarrhea	Notable	High See all 8 studies	Diarrhea can be potently reduced with colostrum under two conditions, either it is being used in persons with HIV-induced diarrhea from cryptosporidium parvum or when using colostrum (from cows immunized to E.coli) in response to food carrying E.coli (usually seen with traveler's diarrhea); despite being highly effective in those two scenarios it seems ineffective in other cases of diarrhea.
	CD4 Lymphocytes	Minor	Low See all 4 studies	While there does not appear to be any influence in healthy controls or with low dose colostrum, higher doses of colostrum in persons with HIV (reduced CD4+ lymphocyte counts) may mildly increase CD4+ counts when compared to whey protein as control.
	Intestinal Permeability	Minor	- See all 3 studies	Evidence is preliminary, and there are studies suggesting both an increase in permeability and a decrease seen with endurance exercise (increase) or with high heat stress exercise or NSAID coingestion (decrease).
	Lean Mass	Minor	Moderate See all 5 studies	Colostrum, inherently due to being a dietary protein, appears to promote lean mass accrual. This is comparable to a similar dose of whey protein as the growth factors in colostrum do not appear to provide an additional benefit.
	Aerobic Exercise	-	Moderate See all 5 studies	For the most part colostrum influenced aerobic exercise similar to whey protein (ie. not much benefit) although in specific instances of high endurance stressors in elite cyclists there may be a small ergogenic benefit thought to be due to reducing the rate of immunosuppression.
	Anaerobic Running Capacity	-	Very High See all 5 studies	There does not appear to be any benefit of dietary colostrum, relative to whey protein, in improving cardiovascular performance in anaerobic instances such as Wingate testing, resisted treadmill tests, or rowing.
	Fat Mass	-	Very High See all 3 studies	Supplementation of colostrum has failed to increase fat mass in subjects relative to baseline, similar to the same doses of whey protein which usually also fail to influence fat mass.
	Fat Oxidation	-	Very High See all 3 studies	Colostrum does not influence fat oxidation rates or glucose expenditure during exercise any differently than other protein sources such as whey.
	Heart Rate	-	Very High See all 4 studies	Heart rate during exercise, either submaximal or at lactate threshold, is not modified with dietary supplementation of colostrum.
	IGF-1	-	High See all 5 studies	While any protein sources has the potential to increase IGF-1 when included in the diet, colostrum is no different than whey protein at doing so. The IGF-1 that is present in colostrum naturally appears to be fully digested in the intestinal tract and does not reach the blood.
	Immunoglobulin A	-	Moderate See all 8 studies	IgA concentrations in saliva and serum do not appear to be reliably increased although a few studies have noted spikes, which do not appear to be consistent in their magnitude nor incidence. The only incidence where IgA appears to be reliably increased is when it is taken as a vaccine adjuvant.
	Immunoglobulin G	-	High See all 4 studies	IgG has been noted to be increased once when colostrum was used as a vaccine adjuvant (relative to skim milk with whey as control), but in general there is no influence without coadministered vaccination.
	Immunoglobulin M	-	Very High See all 3 studies	IgM does not appear to per se be modified in serum relative to control protein, and unlike the other immunoglobulins there is no augmentation of a vaccine-induced IgM spike.
	Lactate Production	-	Very High See all 4 studies	Lactate production during physical exercise does not appear to be any different with dietary colostrum when compared to whey protein.
	Length of Sickness	-	Very High See all 4 studies	Despite tenuous evidence suggesting a reduction in the frequency of sickness with colostrum, when sickness does occur there is no benefit of colostrum in reducing how long it occurs for.
	Power Output	-	Very High See all 9 studies	For the most part and aside from one pilot study, there is no consistent or remarkable increase in power output seen with colostrum that is not replicated by whey. Protein, inherently, may increase power output when combined in the diet over longer periods though.
	VO₂ Max	-	Very High See all 6 studies	All studies assessing the effects of colostrum in athletes subject to cardiovascular training have failed to find any difference between colostrum and whey protein (control) for influencing VO2 max.
	Fatigue	Notable	Very High See 2 studies	Both studies on fatigue assessed persons with HIV-related diarrhea, but when diarrhea was successfully (and greatly) benefited with colostrum containing porridge fatigue was reduced by over 80% of baseline values. It is uncertain if this anti-fatigue effect influences other persons.
	Symptoms of Ulcerative Colitis	Notable	- See study	One study using a solution of colostrum (as enema) in persons with distal colitis noted a large suppression of symptoms and inflammation relative to placebo. No studies available on oral supplementation of colostrum for inflammatory bowel diseases.
	Abdominal Pain	Minor	- See study	One study noted a reduction in abdominal pain associated with the successful treatment of diarrhea.
	CD8 Lymphocytes	Minor	Moderate See 2 studies	At baseline CD8+ lymphocytes do not appear to be altered, although one study noted that the expected decrease in these lymphocytes during exercise was attenuated with colostrum (resulting in a relative increase to whey control).
	Glucagon-like Peptide 1	Minor	- See study	An exercise increase in GLP-1 seen in placebo was attenuated with colostrum administration, thought to be related to the reduction in gut permeability seen with colostrum.
	Insulin Secretion	Minor	- See study	Insulin is secreted in response to colostrum intake due to it being a dietary protein, but this response does not seem to be different from whey protein in magnitude.
	Macrophage Activity	Minor	- See study	One study investigating acute usage of colostrum noted an increase in macrophage phagocytic activity, although as this study noted other immune variables were normalized after a day the long term implications of colostrum on this parameter are uncertain.
	Muscle Protein Synthesis	Minor	- See study	There is an increase in protein synthesis with colostrum relative to maltodextrin due to colostrum being a dietary protein, but there is also an increase in protein breakdown seen; efficacy of colostrum relative to other protein sources in MPS is currently not well investigated.
	Upper Respiratory Tract Infection Risk	Minor	- See all 3 studies	There may be a minor reduction in the incidence of upper respiratory tract infections (URTIs) seen with colostrum, although more evidence is needed to confirm this activity as current trials are usually underpowered.
	Vaccine Augmentation	Minor	Moderate See 2 studies	Tenuous evidence for an increase in vaccine efficacy, as while the one study assessing antibody titres failed to find any influence (suggesting no benefit) there does appear to be a reliable increase in the secretion of IgA and IgG in response to the vaccine.
	B-Cell Count	-	- See study	The overall count of B cells in response to supplementation does not differ between colostrum and whey protein, both seeming to be without any effect.
	Blood Acidity	-	Moderate See 2 studies	While one study noted an increase in buffering capacity of the blood (reduction in acidity), this observation failed to be replicated in another study and both failed to find an ergogenic effect thought to occur after such an increase in buffer capacity.
	Body Temperature	-	- See study	In assessing the effects of colostrum on gut permeability during exercise (secondary to an increase in body heat), colostrum benefited permeability without modifying body heat.
	C-Reactive Protein	-	Very High See 2 studies	C-reactive protein does not appear to be significantly influenced with supplementation of colostrum relative to control or baseline values.
	Cell Adhesion Factors	-	- See study	Cellular adhesion factors on immune cells do not appear to be modified with colostrum relative to whey protein.
	Cortisol	-	Moderate See all 3 studies	While one study noted an increase in morning cortisol during multiple day training in elite cyclists (a beneficial response), basal cortisol concentrations and those immediately after standard exercise do not appear to be influenced with colostrum supplementation.
	Exercise-Induced Immune Suppression	-	Very High See 2 studies	The limited studies assessing sickness in athletes during exercise have not found a significant reduction in sickness rates relative to control protein sources (whey).
	Ghrelin	-	- See study	Circulating ghrelin does not appear to be modified in response to colostrum supplementation.
	Glucagon-like Peptide 2	-	- See study	Circulating levels of GLP2 do not appear to be significantly influenced relative to control protein.
	Hemoglobin	-	Very High See 2 studies	There does not appear to be an inherent increase in hemoglobin with colostrum, although when it successfully treated HIV-associated diarrhea an increase in hemoglobin was noted once (thought to partially underlie the reduction in fatigue).
	Immunity	-	- See study	DTH responsiveness (indicative of T-cell mediated immunity) was not affected with colostrum in adults overall or in the elderly cohort which are normally more responsive to therapeutic interventions on DTH responsiveness.
	Immunoglobulin E	-	Very High See 2 studies	With exceptions to possible milk allergies (where an increase in IgE occurs with the allergic reaction), there is no influence of colostrum on baseline IgE concentrations.
	Interferon Gamma	-	- See study	IFN-y does not appear to be influenced with supplementation of colostrum relative to control proteins (whey).
	Interleukin 1-alpha	-	- See study	Supplemental colostrum does not appear to influence circulating concentrations of IL-1α when compared to whey control.
	Interleukin 10	-	Very High See 2 studies	IL-10 does not appear to be significantly influenced with colostrum relative to baseline or other protein sources.
	Interleukin 6	-	Very High See 2 studies	IL-6 does not appear to be influenced with supplementation of colostrum.
	Interleukin 8	-	- See study	IL-8 does not appear to be significantly influenced with supplementation of colostrum relative to placebo.
	Intestinal Parasites	-	Very High See all 3 studies	Even in cases where traveler's diarrhea (from E.coli) is successfully treated, the overall amount of bacteria found in the stool is not modified suggesting no actual antibacterial properties.
	Lactate Threshold	-	Very High See 2 studies	Colostrum supplementation, relative to control proteins, does not appear to increase the lactate threshold (despite this being increased by training per se to a similar degree with or without colostrum).
	Lymphocyte Count	-	- See study	Overall lymphocyte count does not appear to be significantly influenced with supplementation of dietary colostrum.
	Monocyte Count	-	- See study	Monocytes do not appear to be influenced in their number with supplementation of colostrum.
	Muscular Endurance	-	- See study	Supplementation of colostrum, relative to whey protein, does not appear to promote greater increases in muscular endurance (as assessed by bench press repetitions) when taken alongside a training regimen.
	Natural Killer Cell Activity	-	- See study	The phagocytic activity of natural killer cells does not appear to be modified with supplementation of colostrum relative to whey control.
	Natural Killer Cell Content	-	Moderate See 2 studies	There does not appear to be a sustained influence on NK cell content relative to controls, although one study noted very transient decreases (which were shortly normalized).
	Neutrophil Count	-	Very High See 2 studies	The overall amount of neutrophils in serum does not appear to be modified with supplementation of colostrum relative to placebo.
	Rate of Perceived Exertion	-	- See study
	Severity of Sickness	-	Moderate See 2 studies	While in children with IgA deficiency colostrum appeared to reduce the severity of sickness when supplemented at the onset of sickness, this same effect was not observed in adults with suspected upper respiratory viral infections.
	T Cell Count	-	- See study	In otherwise healthy individuals, colostrum does not alter overall levels of T cells relative to baseline or control proteins.
	TNF-Alpha	-	Very High See 2 studies	TNF-a is not affected by supplementation of colostrum.
	Testosterone	-	Moderate See all 3 studies	While one study noted a preservation of testosterone circadian rhythm during a five day cycling race (where testosterone tends to flatline), other studies have failed to find any influence on basal testosterone concentrations.
	Ventilatory Threshold	-	- See study	Ventilatory threshold does not appear to be significantly influenced with supplementation of colostrum relative to control proteins.
	Viral Load	-	- See study	Administration of colostrum to persons with HIV already on antiretroviral therapy does not further modify viral titres.
	White Blood Cell Count	-	Moderate See 2 studies	White blood cell count does not appear to be chronically modified with colostrum supplementation, although a transient (one day) elevation was noted in one study.
	Blood Glucose	Minor	- See study	Preliminary trial in type II diabetics noted a reduction in fasting glucose concentrations to 10-14% with four weeks of colostrum supplementation; no control was used for reference.
	Fecal Weight	Minor	- See study	A decrease in fecal weight has been noted in a trial assessing diarrhea, which was thought to be a consequence of successfully treating diarrhea.
	Ketone Bodies	Minor	- See study	A decrease in ketone bodies in type II diabetics was noted with supplementation of colostrum daily for four weeks; the decrease was mild, and there was no protein containing placebo for comparison.
	Total Cholesterol	Minor	- See study	A mild decrease in total cholesterol has been noted with supplementation of colostrum in type II diabetics.
	Triglycerides	Minor	- See study	In type II diabetics, triglycerides in fasting conditions were noted to be reduced relative to baseline with colostrum ingestion.
	Growth Hormone	-	- See study	There does not appear to be a significant influence of colostrum supplementation on circulating GH following oral supplementation relative to other protein sources.

Studies Excluded from Consideration

• Used a continuous nasogastric infusion^[1]