Colostrum supplements for gut health. What the evidence says

In 2026, a large trial gave 850 travellers either a special colostrum product or a placebo. The product was made to fight a common cause of traveller’s diarrhoea. It did not lower the overall risk in any meaningful way.

That result sits beside a lot of hype. Colostrum supplements are sold as gut healers, immune boosters and leaky gut fixes. In this guide I look at what the research really shows, where it is promising and where it falls short.

What is a colostrum supplement?

A colostrum supplement is dried “first milk” from cows, sold as a powder or capsule. Colostrum is the thick milk a cow makes in the first days after giving birth, before normal milk comes in.

It is rich in active ingredients. A 2025 review lists antibodies (mainly a type called IgG), lactoferrin, growth factors, milk sugars called oligosaccharides and small proteins called peptides. In lab and animal work, these help repair the gut lining, calm inflammation and support gut bacteria.

Most products use bovine colostrum, which means it comes from cows. Some products are “hyperimmune”, made from cows vaccinated against a specific germ so their colostrum carries extra antibodies to it.

Does colostrum help your gut lining?

Colostrum may help protect the gut lining under heavy stress, but the human studies are tiny. Most come from one research group and measure lab markers, not how people feel.

Your gut lining acts like a filter. When it lets more through than it should, doctors call it increased gut permeability.

The painkiller study

A 2001 study gave 7 healthy men a strong painkiller called indomethacin for 5 days. With a whey protein drink, their gut permeability rose about 3 times. With colostrum, it did not rise significantly.

The same paper also tested 15 patients already taking painkillers long term. Colostrum made no difference for them. A 2026 study also found this painkiller test may be less reliable than researchers thought.

The heavy exercise studies

Hard exercise in the heat can make the gut more leaky. In a 2011 study, 12 volunteers took colostrum or a placebo for 14 days before a standard workout. On placebo, gut permeability rose 2.5 times. Colostrum cut that rise by 80%.

A 2016 trial with 8 volunteers found something similar. After 14 days, colostrum or zinc carnosine cut the rise in permeability by 70%. Taking both together worked a little faster.

These results are interesting for athletes. Yet 8 to 12 people is a very small number. The studies measured sugar tests in urine, not bloating, pain or bowel habits.

Can colostrum help IBS or bloating?

There is no good evidence yet that colostrum helps IBS or bloating. When I searched PubMed in November 2026, I found no placebo-controlled trial of colostrum in adults with IBS.

The 2025 review I mentioned called colostrum promising for IBS and other gut conditions. Yet it relied heavily on animal models, lab work and small human studies. A 2021 lab study suggested colostrum could protect gut cells from bacteria linked to SIBO. Its authors work with a company that sells colostrum, and cells in a dish are not people.

Colostrum is also a dairy product. If milk sugar, called lactose, upsets your gut, a colostrum powder could make bloating worse. My guide to lactose and IBS explains how to tell. If bloating is your main problem, my list of bloating causes is a better place to start.

Does colostrum help with diarrhoea?

The evidence for diarrhoea is mixed. It looks a little better for infections in children than for anything else.

In children

A 2019 meta-analysis pooled 5 trials in children with infectious diarrhoea. Colostrum lowered stool frequency by about 1.4 times a day. It also lowered the odds of diarrhoea by 71%.

Yet a 2025 systematic review of 8 studies in children came to a more careful view. The studies used different doses, products and outcomes. The authors said no conclusion can be drawn about colostrum and children’s gut health.

In travellers

The 2026 trial from the start of this article was large and well designed. It included 850 military staff and adult civilians heading to high-risk regions. They took 600 mg of a hyperimmune colostrum twice a day, or a placebo.

Traveller’s diarrhoea hit 22.7% of the colostrum group and 26.3% of the placebo group. That gap was too small to count as a real effect. Side effects were rare and mild. My guide to travelling with IBS covers steps with better support.

In premature babies

Colostrum has been tested in very premature babies too. A 2026 meta-analysis of 4 trials with 670 babies said it cannot be recommended. Another 2026 trial in 146 babies found it safe but no better than a standard milk fortifier.

Does colostrum boost your immune system?

Colostrum may reduce colds in people who train hard, but the evidence is low quality. A 2016 meta-analysis pooled 5 trials with 152 adults who exercised regularly.

Over 8 to 12 weeks, colostrum cut days with upper respiratory symptoms by 44%. It also cut new episodes by 38%. Yet 4 of the 5 studies had a moderate or high risk of bias.

A 2020 meta-analysis of 10 trials with 239 active people found almost no change in antibody levels or immune cells in the blood. A 2023 trial in medical students found fewer days with cold symptoms on a low dose of 0.5 to 1 g a day. One author was paid by the company that made the colostrum.

Why does the gut matter here?

I strongly believe your gut is where much of your health begins. Your gut lining, your gut bacteria and the immune cells in your gut wall all work together. That is why a product that claims to support all three sounds so appealing.

Colostrum may play a small part in that system, but food plays a far bigger one. Fibre feeds the bacteria that help keep your gut lining strong. Fermented foods bring in live microbes. My guide to kefir for gut health shows what one fermented drink can and cannot do.

Is colostrum safe?

For most healthy adults, colostrum appears well tolerated in short trials. In the 2026 traveller trial, only 2 of 320 people on colostrum reported side effects, and both settled on their own.

Still, take care in these situations.

• Milk allergy. Colostrum comes from cows, so avoid it if you are allergic to cow’s milk protein.
• Lactose intolerance. Some products contain lactose. Check the label or start with a very small amount.
• Pregnancy and breastfeeding. There is little safety research, so ask your doctor first.
• Babies and children. Only use colostrum for a child if their doctor advises it.
• Quality. Supplements are not checked as strictly as medicines. Choose a brand with independent third-party testing.

Should you try colostrum supplements?

I would not start with colostrum supplements for gut health. The research is too small, too early and too often linked to the companies that sell them. Doses in studies also ranged widely, from 0.5 g a day to 40 g around a long bike ride.

If you still want to try one, treat it as a short test, not a cure.

Try this

1. Build the base first. Eat a wide range of plants each week. My game Gut Garden makes this easy to track.
2. Add a fermented food you enjoy. Plain kefir or yogurt is a cheaper way to bring live microbes into your day.
3. Pick a tested product. If you choose colostrum, look for third-party testing and a clear dose on the label.
4. Test it for 4 weeks. Keep a short diary of bloating, pain and bowel habits before and during.
5. Stop if it upsets your gut. Extra wind, bloating or loose stools may point to lactose.
6. Calm your stress. Stress affects your gut lining too. My free 30-Day Calm Gut Challenge helps one day at a time.

If you have IBS, a guided plan gives you far more to work with. Start with my IBS diet guide, then look at probiotics for IBS, which have much more research behind them.

When should I see a doctor?

See a doctor before relying on any supplement if your gut symptoms are new, severe or getting worse. Diarrhoea that lasts more than a few weeks needs a proper check, not a powder.

Get help quickly if you notice blood in your stool, night-time diarrhoea or weight loss without trying. Losing 3 kg (about 7 lb) or more without trying is always worth a check. My guide to IBS vs IBD explains the warning signs.

Frequently asked questions

What does colostrum do for your gut?

Colostrum contains antibodies, lactoferrin and growth factors that support the gut lining in lab and animal studies. In tiny human studies, it reduced the rise in gut permeability caused by heavy exercise or a strong painkiller. There is no good trial yet showing it eases everyday gut symptoms.

Is colostrum good for leaky gut?

Small studies suggest colostrum can limit a short-term rise in gut permeability during hard exercise. Those studies had only 8 to 12 people and measured lab markers. There is no proof that colostrum treats “leaky gut syndrome”, which itself is not a proven diagnosis.

Can colostrum cause bloating or diarrhoea?

Most people tolerate colostrum well in trials, and side effects were rare in a large 2026 study. Because it is a dairy product, it may contain lactose. If you are sensitive to lactose, it could cause wind, bloating or loose stools, so start small.

Who should not take colostrum?

Avoid colostrum if you have a cow’s milk allergy. Ask your doctor first if you are pregnant, breastfeeding, have a weak immune system or take regular medicines. Do not give it to babies or children unless their doctor advises it.

What I want you to remember

Colostrum supplements are interesting, but the evidence for gut health is thin. The gut lining studies are tiny, the IBS trials do not exist yet and a large traveller trial was disappointing.

Spend your money and energy on the basics first. Eat a wide range of plants, add a fermented food you enjoy, sleep well and calm your stress. For a full plan, start with my complete IBS diet guide.