Why a ‘liquid gold’ substance for cows is making waves with humans

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Colostrum, the first milk produced by humans and other mammals in the earliest days after giving birth, is “liquid gold,” said Dr. Jennifer Smilowitz.

“It is packed full of nutrients, but also molecules that aren’t necessarily nutrients — they’re like these biologically active compounds that are actually protective,” said Smilowitz, an assistant professor in the department of nutrition at the University of California, Davis, whose research background is in breastfeeding, nutrition, lactation and the microbiome.

These nutrients and compounds include immunoglobulins (or antibodies), white blood cells, vitamin A, magnesium, copper, zinc, growth factors and a variety of other components essential for jump-starting life, including the strength and structure of the immune system and the gut, experts said.

These growth factors strengthen permeable, leaky intestines, sealing the gut and preventing bad bacteria or pathogens from flowing into the bloodstream in an unregulated way, Smilowitz said. The colostrum protects an infant during a vulnerable stage.

But “today we have seen a huge rise in colostrum supplements for consumption in adults — with some hefty health claims that may or may not be true,” said Caroline Thomason, a dietitian and diabetes educator based in Virginia, via email.

Colostrum supplements, often derived from cows, are popular for their potential to boost immunity, improve gut health and enhance athletic performance, said Dr. Lisa Young, a registered dietitian nutritionist and adjunct professor of nutrition at New York University in New York City, via email.

Collected from dairy cows within the first several days after birth and processed and pasteurized to be safe for human consumption, bovine colostrum is available in forms such as powders, pills and liquids, and as an enema.

“It’s a delicate process because it involves preserving the bioactive compounds while ensuring the product is safe for consumption,” Thomason said.

“The rise of influencers talking about colostrum supplements seems to have contributed to the boom (in consumption) in the last year or so,” she added.

Celebrities, too, have been touting colostrum as a health tool — social media personality and model Sofia Richie included the supplement in the $21 smoothie she launched with the upscale California-based grocery store Erewhon, and so did artist The Kid LAROI.

“However,” Thomason added, “it’s important to note that while these benefits sound exciting, the research on colostrum is still relatively new and not entirely conclusive.”

How colostrum affects human health

One main reason some people turn to colostrum for health benefits is due to gut inflammation that makes their physiology resemble that of a vulnerable infant, Smilowitz said.

That inflammation can be due to ulcerative colitis, Crohn’s disease, chronic infections, chronic diarrhea or HIV, or the effects of chemotherapy or radiation, she added.

“There is some preliminary evidence that colostrum can support immunity and gut health, particularly in people with compromised immune systems or intestinal permeability issues,” Thomason said. Some small studies have found colostrum may boost growth of intestinal cells and strengthen the walls of the gut.

Other research has suggested benefits for respiratory tract infections. One 12-week study of 35 adult distance runners found taking a colostrum supplement daily increased the amount of certain antibodies in their saliva by 79%, which the authors thought could strengthen participants’ ability to fight infections. There were similar results in a separate study of 29 male cyclists, with a daily dose of 10 grams for five weeks associated with less decline in immune cells after exercise and a greater reduction in risk of respiratory infection.

It’s important to note that the results of these studies merely indicated changes in immune biomarkers — but not necessarily outcomes or improvements in events within the immune system, such as getting sick, said Julie Stefanski, a Pennsylvania-based registered dietitian nutritionist and spokesperson for the Academy of Nutrition and Dietetics.

“And then sometimes the dose that’s used in the study is much, much higher than what’s sold in a supplement,” Stefanski added.

There are also anecdotal reports of improvement in skin health and exercise recovery, but scientific research in these areas is still lacking, Thomason said. There’s also no strong evidence supporting claims of weight loss or the reversal of age-related changes.

There’s also the matter of who pays for the research. Supplement or dairy companies, or health experts affiliated with them, have funded most of the research on colostrum supplements, which largely hasn’t been replicated, experts said. Some studies have also had mixed results, Smilowitz added.

Before you buy it

As with any supplement, consulting a health provider before starting and following the manufacturer’s instructions are crucial, Thomason said, especially if you have a gastrointestinal condition.

“Colostrum supplementation is generally considered safe for most people, but there are risks, particularly for folks with milk allergies. Large doses could potentially lead to digestive upset, such as bloating or diarrhea,” Thomason said. Children and people who are pregnant or breastfeeding should also avoid taking colostrum.

“Plus, these supplements are expensive, and you may not see any health improvements at all,” Thomason added.

The cost of colostrum supplements can range from around $15 to $200 per bottle, partly depending on the quality — which is important since a higher calibermeans a lesser risk for contamination, Young said.

Quality is determined by factors such as the health of the cow, its environment and diet, if it has been vaccinated, the season, its breed, the length of time between pregnancies and the time of colostrum collection, Smilowitz said.

Though calves need to receive the first of the colostrum, colostrum collected on day three or four is more healthful than colostrum gleaned a week later. Given the sensitivity of the collection process, a supplement that’s on the cheaper end is probably less effective, Stefanski said.

Additionally, colostrum from grass-fed and pasture-raised cows is better than conventionally raised cows.

Since the US Food and Drug Administration does not pre-approve supplements for safety and efficacy as it does for prescription drugs before they reach the market, knowing which colostrum supplements are more worth your money than others can be tricky.

But to choose the highest-quality supplement possible, look for products that are tested by a third party for quality and purity, recommended Keri Gans, a New York state-based registered dietitian nutritionist.

You can also check a manufacturer’s website or contact its customer service for more details that might not be on the packaging, experts said.

“While colostrum may offer some health benefits, it’s not a magic bullet, and more research is needed to fully understand its effects and long-term safety,” Young said.

Prioritizing a healthy, balanced diet as well as exercise and sleep will improve your health far more, Thomason said.

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