Colostrum properties - is it worth it for adults 2026

Bovine colostrum is sold today as support for immunity, gut health, and post-workout recovery, and each of these claims has different levels of evidence. Some claims are based on studies with humans, some on mechanisms described in the laboratory, and some solely on packaging. Additionally, there is a problem that manufacturers do not mention: two products with the same declared content of immunoglobulins can differ in biological activity by six times. This article separates these layers. It shows what remains of colostrum after passing through the stomach, what doses were actually used in studies, where the results are consistent, and where one study contradicts another. You will also find a list of individuals who should not use colostrum.

KEY INFORMATION
• The biological activity of twenty commercial colostrum products varied sixfold (Playford, PLoS One, 2020).
• In a study with 53 men, 20 g of colostrum daily for 12 weeks reduced the number of days with upper respiratory infections, with no effect on secretory IgA in saliva.
• Supplementation does not raise IGF-1 levels in the blood in adults.
• Results regarding intestinal permeability are mixed: one study shows an increase after eight weeks.

How does colostrum differ from regular milk?

By the concentration of defensive proteins, not their presence. Colostrum is a secretion from the mammary gland in the first days after birth and contains the same fractions as mature milk, only in quantities one or two orders of magnitude larger. The biggest difference concerns immunoglobulin G, which in ruminants serves a role that it does not necessarily have to serve in humans.

The reason is anatomical. The cow's placenta does not transfer antibodies to the fetus, so the calf is born practically without immunoglobulins in its blood and receives all protection through the digestive tract in the first hours of life. In humans, the placenta transports IgG in the third trimester, so the newborn already has its own supply. This difference explains why bovine colostrum is so concentrated.

The compilation comes from a review dedicated to the composition and applications of bovine colostrum (Playford i Weiser, Nutrients, 2021). It reveals something that marketing usually overlooks: the advantage of colostrum over milk is significant for immunoglobulins and lactoferrin, but diminishes with lactoperoxidase and lysozyme, where the ranges in both fluids overlap. The same study states that lactose constitutes about 2.5% in colostrum, which is less than in mature milk, and the concentration of lactoferrin in bovine colostrum reaches only about 10% of human values.

What else does colostrum contain besides immunoglobulins?

Casein, oligosaccharides, antibacterial enzymes, and growth factors, some of which play a role that product descriptions remain silent about. The most interesting is the contribution of components that do not act on their own but protect others.

Casein is a good example here. A review of the composition of colostrum describes it not only as a source of energy but also as a protein with immunoregulatory and antibacterial properties, partially protecting epidermal growth factor from digestion and improving the stability and absorption of insulin-like growth factor (Playford i Weiser, Nutrients, 2021). The natural packaging of these molecules is therefore important, and isolating a single fraction may not yield the same effect.

Oligosaccharides are present in colostrum at about 1 g/L, roughly twice as much as in mature milk. Most of them are not digested in the upper gastrointestinal tract, thus acting prebiotically. Lactose also provides galactose and glucose used in glycogen synthesis.

Enzymes create a separate chemical defense system. Lysozyme breaks down the cell wall of bacteria, while lactoferrin enhances its action against Escherichia coli. The same study notes that using a formula for infants devoid of lysozyme, instead of one containing this enzyme, was associated with three times more frequent diarrhea.

What remains of colostrum after passing through the stomach?

More than intuition about protein digestion would suggest, but not enough for anything to enter the bloodstream. A review dedicated to the action of bovine immunoglobulins in humans states that very small amounts to 50% of ingested IgG were recovered in feces, with the percentage in infants being higher than in adults due to differences in stomach pH and intestinal conditions (Ulfman, Frontiers in Nutrition, 2018).

The authors draw a conclusion significant for the entire topic: bovine IgG may be active throughout the length of the gastrointestinal tract. It binds many human pathogens and allergens, neutralizes cell infection in experimental conditions, reduces inflammation in the intestine, and binds to human Fc receptors, enhancing phagocytosis and antigen presentation. This is a local action, not systemic.

Some proteins do not just survive but change into something active. Lactoferricin is formed from lactoferrin as a result of digestion by pepsin in an acidic environment, which is a reaction that occurs naturally in the stomach, and retains the antibacterial activity of the original protein, often stronger (Gifford, Cellular and Molecular Life Sciences, 2005).

The boundary is set by the mature intestinal barrier. In adults, intestinal permeability limits the passage of these molecules into circulation, which is confirmed by the observation that the consumption of large amounts of colostrum did not raise IGF-1 levels in plasma in healthy adults (Playford and Weiser, 2021). Therefore, everything colostrum does in an adult occurs in the intestinal lumen.

Does colostrum reduce the number of infections?

In physically active individuals, yes, and this was shown in a randomized placebo-controlled study, but the mechanism turned out to be different than expected. This is an important distinction because the most commonly repeated explanation of colostrum's effect on immunity was not validated in the same study that demonstrated the clinical effect.

In the winter months, 53 men were assigned in a double-blind manner to receive 20 g of colostrum daily or an isoenergetic placebo with a similar macronutrient composition for 12 weeks. In the colostrum group, the percentage of days with upper respiratory infections and the number of episodes were significantly lower than in the placebo group (Jones, Brain Behavior and Immunity, 2014).

However, the same study did not confirm any of the previously proposed mechanisms. Colostrum did not affect the oxidative burst of neutrophils studied ex vivo, secretory IgA in saliva, or salivary antimicrobial peptides. The authors did find something else: in a subgroup of participants, the bacterial load in saliva increased over 12 weeks in the placebo group, while in the colostrum group, this increase was less pronounced.

A narrative review dedicated to the applications of colostrum in sports assesses this area similarly. Evidence of its impact on body composition and physical performance is limited, while stronger evidence exists regarding permeability and intestinal damage, as well as immunity and disease risk, especially during periods of intensified training (Davison, Nutrients, 2021).

Does colostrum seal the intestines after exercise?

Two studies say yes, one says otherwise, and the difference between them lies in the duration and dosage. This is the best-documented area of colostrum's action in adults, but the consistency of results is often exaggerated in commercial descriptions.

Twelve volunteers underwent a double-blind crossover protocol with 14 days of colostrum or placebo before standardized exercise. Intestinal permeability was measured by the ratio of lactulose to rhamnose in urine over five hours. In the placebo arm, exercise increased it 2.5 times, from 0.38 to 0.92, while in the colostrum arm, the increase was limited by 80%, to 0.49 (Marchbank, American Journal of Physiology, 2011).

A similar effect was previously described for drug-induced damage. In a crossover study with seven healthy volunteers, indomethacin at a dose of 50 mg three times a day for five days caused a threefold increase in permeability in the control arm, which was not observed when colostrum was administered simultaneously. In fifteen patients chronically taking anti-inflammatory drugs, baseline permeability was low and the preparation did not change it (Playford, Clinical Science, 2001).

The opposite result was obtained in a long study. Thirty men ran three times a week for eight weeks, taking 60 g of colostrum, whey protein, or nothing. After eight weeks, the ratio of lactulose to rhamnose increased by 251% in the colostrum group, compared to 21% with whey and a decrease of 7% in the control group (Buckley, Nutrients, 2009). The authors allow that colostrum increases the transport of large molecules across the epithelium, just as it does in the intestines of newborns.

A systematic review encompassing nine studies concludes with a moderate statement: colostrum may improve intestinal permeability in athletes, but well-designed randomized studies are needed to assess long-term safety and establish a dosing regimen (Dziewiecka, Nutrients, 2022).

How does colostrum affect intestinal epithelial cells?

Through growth factors, not immunoglobulins, and this can be demonstrated by blocking individual pathways. This part of the research explains why products with similar declared compositions can behave differently.

In a study of the activity of twenty commercial preparations, neutralizing transforming growth factor beta reduced the ability to stimulate epithelial cell migration by 83%, without affecting cell division. Blocking the epidermal growth factor receptor reduced migration by 23% and proliferation by 55% (Playford, PLoS One, 2020). Thus, two different molecules are responsible for two different phenomena.

A similar picture emerged from an accompanying experiment in a study on exercise. Raising the temperature of intestinal cells by 2 degrees Celsius increased apoptosis by 47 to 65%, while the presence of colostrum limited this effect by 60%. The decrease in electrical resistance of the epithelium, a measure of the tightness of the cell layer, was limited by 64%. Colostrum also increased the expression of heat shock protein HSP70, and this effect disappeared after adding an antibody blocking the epidermal growth factor receptor (Marchbank, American Journal of Physiology, 2011).

For the reader, one practical conclusion emerges from this. Since the action depends on preserved growth factors, which lose activity with mild heating, the method of production and preparation of portions weighs more than the number on the label. A preparation subjected to higher thermal processing may have a complete set of proteins as indicated but lack what provided the effect in these experiments.

Does colostrum improve athletic performance?

There is little evidence for this, and it is weaker than in the intestinal and immune areas. A review covering a quarter-century of interest in colostrum in sports nutrition states outright that data regarding body composition and physical performance are limited (Davison, Nutrients, 2021).

The authors note one exception. Some studies have shown protection against declines in performance caused by periods of intensified training, meaning an effect that not only improves fitness but also prevents its deterioration during a challenging preparation block. This distinction is practically significant, as it pertains to an athlete at peak loads, not someone exercising twice a week.

The issue of building mass has been resolved separately. Since supplementation does not raise systemic levels of insulin-like growth factor, the mechanism by which advertising explained its alleged impact on hypertrophy disappears. Colostrum does not replace whey protein or an adequate energy supply in this role.

The practical expectation is thus: colostrum is a tool for gut protection and reducing the number of days lost to infections, not a means of increasing strength or speed. If you are looking for a performance effect, seek it elsewhere and check the evidence for other ingredients marketed to athletes.

Does colostrum raise growth hormone levels?

Not in adults, and this is one of the better-resolved points today. The concern is understandable, as colostrum contains growth factors, and insulin-like growth factor is sometimes associated with oncological risk when elevated for prolonged periods. Measurements do not confirm this.

Early assumptions that supplementation with colostrum products could raise systemic IGF-1 levels are not supported by the entirety of available data covering various doses over short and long periods (Davison, Nutrients, 2021). A review of colostrum composition describes the same result from a physiological perspective: in adults, limited gut permeability retains most of these molecules, and consuming large amounts of the product did not raise IGF-1 levels in plasma.

A caveat that must be noted was formulated by the authors of the review themselves. Systemic absorption could be significant in disease states where gut permeability is increased. A person with active inflammatory bowel disease is therefore not in the same situation as a healthy runner.

The practical conclusion is twofold. On one hand, the marketing argument that colostrum builds muscle mass through growth factors is eliminated. On the other hand, the fear of hormones is also unfounded, as they do not reach the bloodstream. Colostrum acts in the gut, and that is where its effects should be sought.

Jakie dawki stosowano w badaniach?

From a few to sixty grams per day, over a period of a few days to three months, depending on what was studied. The following numbers are research protocols, not recommendations for the reader, as no one has yet established an optimal dose for adults.

The review of sports applications states the matter plainly: studies on the dose-effect relationship would be valuable for determining the lowest effective dose, but they are complicated by variability in activity among products, meaning that the results of such studies would only apply to the specific products used (Davison, Nutrients, 2021). This statement explains why you won't find a single number on the packaging in this entry.

If you are looking for a comparison with other ingredients used for immunity, they are described separately in entries about kwercetynie oraz o oleju z czarnuszki.

Why do two packages of colostrum work differently?

Because they differ in biological activity, not just the declaration on the label. This is the most practical finding in the entire topic and also one that no label reveals.

Twenty commercial colostrum products intended for humans were tested, evaluating their ability to stimulate division and migration of intestinal epithelial cells. Differences between products reached sixfold. The comparison of the most and least active products translated into results in an animal model: stomach damage decreased by 86% with the most active sample compared to 48% with the weakest (Playford, PLoS One, 2020).

The authors pointed out two probable causes of this discrepancy. The first is heat treatment: heating the powder to 50 degrees Celsius for an hour did not change the immunoreactivity of IgG, lactoferrin, EGF, or IGF-1, yet it reduced biological activity by over 40%. The second is the contribution of the first milkings. Activity was high in the first and second milkings on the day of birth, and by the third day, it had dropped by 77%.

This leads to a conclusion that undermines the most commonly used purchasing criterion. The declared percentage of immunoglobulins does not indicate the activity of the product, as the protein may be present and detectable by immunological testing, yet still lack efficacy. The authors themselves propose assessing biological activity as a better quality control method than measuring growth factor concentrations.

Where does the colostrum used in studies come from?

From several different sources, and this is one of the reasons why results are difficult to compare. Under one name, products of different origins are hidden, and studies rarely use the same material.

The review dedicated to bovine immunoglobulins lists four typical sources used in studies with humans: immunoglobulins obtained from serum, colostrum itself, immunoglobulins isolated from colostrum, and immunoglobulins from milk (Ulfman, Frontiers in Nutrition, 2018). Many studies used material from cows vaccinated against specific pathogens, but efficacy has also been described for material from unvaccinated animals.

Additionally, there are differences in the study group, design, dose, and measured endpoints, making it difficult for the authors to draw general conclusions about the effectiveness of products rich in bovine immunoglobulins. This caution is usually overlooked in commercial texts, yet it sets the boundary for what can be promised.

The day of milking also matters. Biological activity was highest in the first and second milkings on the day of birth, and by the third day, it had dropped by 77%, which was noted alongside a decrease in total protein content and growth factors (Playford, PLoS One, 2020). Products collected over a broader time window are therefore inherently weaker than those from the first hours.

Powder or capsules?

Powder if you care about quantities comparable to those in studies. The calculation is simple, and it is this that decides, not the convenience of the form.

A capsule contains a fraction of a gram of powder, as that is how much fits into a typical shell. With a capacity of around half a gram, a research protocol of 20 g per day would mean forty capsules a day, and with one gram, twenty. No one will take that regularly, and lozenges and liquid forms contain even less. Powder allows for measuring any amount, at the cost of the characteristic taste of colostrum. Check the weight on the packaging before converting anything into days of use.

That doesn't mean capsules are useless. At doses of around a gram per day, aimed at local action in the intestine, the form doesn't matter much, and convenience increases the chances that supplementation will last longer than a week. The only important thing is not to confuse it with the research protocol and not to expect the same results from it. You can find such preparations in the category supplements.

When choosing, pay attention to three pieces of information: the country of origin of the raw material, the drying method, and whether the manufacturer even provides the conditions for thermal processing. The last point is the least often met, and given the data on the loss of activity at 50 degrees Celsius, it says the most.

How to prepare and store colostrum?

In lukewarm water, never in hot, and in a closed package away from moisture. The recommendation to avoid boiling water has circulated in product descriptions for years, but only the measurement of biological activity shows how low the threshold is.

Heating the powder to 50 degrees Celsius for an hour reduced biological activity by over 40%, even though immunological markers did not show a loss of the proteins themselves (Playford, PLoS One, 2020). Pouring a portion into hot tea or coffee means a temperature clearly higher than in this experiment. Water at room temperature, cold plant milk, yogurt, or a smoothie after cooling are safe options.

The powder itself is hygroscopic, so close the package after each use and keep it in a dry place, away from sunlight. Do not transfer the supply to a transparent jar standing on the counter next to the stove. Keep the scoop dry, as a wet one will clump the rest of the contents.

The time of day has no confirmed significance. The popular advice to take it on an empty stomach thirty minutes before a meal has no basis in studies with humans, and in the protocols cited above, participants took the preparation at various schedules. Regularity is more important here than the hour.

Who should not use colostrum?

People with a cow's milk protein allergy, pregnant and breastfeeding women, and patients taking immunosuppressive medications without the consent of their doctor. Colostrum is a dairy product, and there is no version that stops being one.

IgE-dependent allergy to cow's milk proteins is the most unequivocal contraindication. Colostrum contains casein and whey proteins, including beta-lactoglobulin, which the composition review describes directly as the main immunogen for people allergic to cow's milk and which is not present in human milk (Playford and Weiser, 2021). A declaration of reduced lactose content does not change anything here, as the allergy concerns the protein, not the sugar.

Lactose intolerance is a different situation. Lactose constitutes about 2.5% in colostrum, which is less than in mature milk, so a portion of a few grams of powder contributes very little. In cases of severe intolerance, it is reasonable to start with the smallest amount and observe the reaction over a few days.

A separate group includes individuals whose intestinal permeability is increased due to disease. The authors of the composition review caution that in such conditions, systemic absorption of growth factors could be significant, although it has not been studied. Therefore, in the case of active inflammatory bowel disease, it is wiser to establish a course of action with a gastroenterologist than to apply results obtained from healthy runners.

For pregnancy and breastfeeding, there is a lack of studies to assess safety, which is why manufacturers advise against use during these periods. Caution also applies to autoimmune diseases and after organ transplantation, where any preparation affecting the intestinal immune system requires a discussion with the attending physician, not a decision made in a drugstore.

Does colostrum perform better than vitamin D?

Not in the same category of evidence. Vitamin D has a meta-analysis of individual participant data behind it, while colostrum has single studies on small groups, so the comparison favors the former regardless of the effect size.

The meta-analysis included 25 randomized studies involving a total of 11,321 participants aged 0 to 95 years, and individual data were obtained for 10,933 people, or 96.6% of the sample. Supplementation reduced the risk of acute respiratory infection, with an adjusted odds ratio of 0.88 and a confidence interval from 0.81 to 0.96 (Martineau, BMJ, 2017).

The effect was not evenly distributed. Protection was seen in individuals taking vitamin D daily or weekly, but not in those receiving bolus doses. The strongest effect was observed in individuals with a baseline concentration of 25-hydroxyvitamin D below 25 nmol/l, where the adjusted odds ratio was 0.30. In other words, the greatest benefit was seen in those who were deficient in vitamin D.

The practical priority setting is therefore as follows: first, replenish what you are lacking, and only then consider ingredients with narrower applications. Colostrum makes sense as a tool for a specific intestinal problem or a period of intensified training, not as the first step in building immunity. A similar distinction is made in the entry about cordyceps and endurance.

Frequently Asked Questions

How does colostrum differ from regular cow's milk?

By concentration, not composition. Colostrum contains 34.0-87.0 g/L IgG1 compared to 0.31-0.40 g/L in mature milk and 1.5-5 g/L lactoferrin compared to 0.02-0.75 g/L (Playford and Weiser, Nutrients, 2021). For lactoperoxidase and lysozyme, the ranges for both fluids overlap, so the advantage of colostrum does not apply to all fractions.

Does colostrum boost immunity in adults?

In a study with 53 men, 20 g of colostrum daily for 12 weeks significantly reduced the number of days with upper respiratory infections and the number of episodes compared to placebo (Jones, Brain Behavior and Immunity, 2014). The same study found no effect on secretory IgA in saliva or on neutrophil oxidative burst.

What is the optimal dose of colostrum?

It has not been established. Studies used doses ranging from a few to 60 g daily over periods from a few days to three months. A review of sports applications indicates that studies on the dose-effect relationship are complicated by variability in activity between products, making their results applicable only to specific products (Davison, Nutrients, 2021).

Does the method of preparation destroy active ingredients?

Heating the powder to 50 degrees Celsius for an hour reduced biological activity by over 40%, even though immunological measurements of IgG, lactoferrin, and growth factors showed no loss (Playford, PLoS One, 2020). Therefore, colostrum should be dissolved in lukewarm or cold water, never in hot tea or coffee.

Does colostrum help with intestinal permeability?

The results are mixed. After 14 days of supplementation, the increase in permeability after exercise was reduced by 80% (Marchbank, American Journal of Physiology, 2011), but after eight weeks of taking 60 g daily, the ratio of lactulose to rhamnose increased by 251% compared to 21% with whey (Buckley, Nutrients, 2009).

Does colostrum raise IGF-1 in the blood?

Not in healthy adults. Early assumptions about an increase in systemic IGF-1 are not supported by the entirety of data covering various doses over short and long periods (Davison, Nutrients, 2021). The mature intestinal barrier limits the passage of these molecules into circulation, so the effect remains local.

Who should not use colostrum?

Individuals with IgE-dependent allergies to cow's milk proteins, as colostrum contains casein and beta-lactoglobulin. Caution is advised during pregnancy and breastfeeding, where studies are lacking, as well as with immunosuppressive medications and after organ transplantation, where the decision is made by the attending physician.

Summary

Bovine colostrum is a supplement with a narrow but real range of applications. The two best-documented are: fewer days with respiratory infections in physically active individuals and a reduction in the increase of intestinal permeability caused by exercise or anti-inflammatory medications. The rest of the promises, from muscle hypertrophy to improved skin appearance, currently lack support in studies with humans.

It is also worth remembering what the studies have not resolved. It is unknown what the lowest effective dose is, as comparisons are complicated by the variability of preparations. It is unclear how colostrum behaves with long-term use, as the longest protocols lasted several weeks. Finally, it is unknown whether the conclusions from studies on physically active individuals apply to the rest of the population, as athletes constitute the majority of the studied groups.

Three things are worth remembering before purchase. The biological activity of preparations varies sixfold, and the declared percentage of immunoglobulins does not reflect this. Doses from studies start at a few grams and reach sixty, so one capsule a day is a different order of magnitude. Hot water cancels part of the effect, even though the protein remains detectable.

Colostrum is not the first step either. Regarding the number of respiratory infections, stronger evidence supports replenishing vitamin D deficiency, and the greatest benefit is seen in individuals with the lowest baseline concentration. Consider colostrum when you have a specific intestinal problem or a period of intensified training, not as a general boost. A broader discussion of the ingredient itself is covered in the entry about colostrum beyond infancy.

This article is for informational and educational purposes and does not constitute medical advice. Before starting supplementation, consult your doctor, especially if you are taking medications regularly, are pregnant or breastfeeding, or have a chronic illness.

Author: Michał Waluk · Opublikowano: 2026-05-11 · Aktualizacja: 2026-08-10