Experts have long known that yogurt is a health-boosting food rich in protein, calcium, and other important nutrients. But some studies are exploring a specific question: Can yogurt help prevent colon cancer?
To understand the answer, it’s important to understand more about the ecosystem of microbes that live in your intestine. There are trillions of these bacteria, and some help protect your body, while others cause inflammation or even tumor growth.
This balance of helpful and unhelpful bacteria has a big influence on your health. And many of the lifestyle choices you make impact which types of bacteria thrive in your body, says Christian Jobin, PhD, co-leader of the Immuno-oncology and Microbiome Program at UF Health Cancer Center in Gainesville, Florida.
“A lifestyle that has no physical activity, high alcohol content, a diet rich in fat, and so on, reduces certain nutrients for your gut microbiome to feed on, which in turn could impact your immune system,” Jobin says.
Without enough nutrients that help promote helpful bacteria, the more harmful bacteria are left unchecked, and your gut is less protective against tumor growth. The harmful microbes may also give off toxins that damage your cells and DNA and promote tumors, Jobin says.
What does this have to do with yogurt? Some yogurt — although not all — has probiotics in it. Probiotics are helpful bacteria that can counter harmful microbes and reduce inflammation. It seems like a simple solution: Eat more yogurt, promote more good bacteria, increase your gut’s tumor-fighting power. But it’s a much more complex process, Jobin says.
Your Colon Cancer Risk May Be Increasing
Doctors used to consider colon cancer a disease of older age, but rates are rising drastically in younger people. About 1 in 5 colon cancer diagnoses happens in people under 55. Experts think environmental and lifestyle changes may be one of the reasons for this shift.
Jobin says most colorectal cancers are not genetic and develop on their own. “That means most of the time they’re linked to the environment, lifestyles, and many other things surrounding yourself, including the gut microbiome.”
Studies show that some of the risk factors for colon cancer include obesity, diabetes, smoking, and alcohol use. But also, a diet high in processed foods and low in fiber can increase your risk, too. That’s where yogurt comes in.
How Does Yogurt Impact Your Colon Cancer Risk?
Experts recommend high-fiber foods and fermented foods like yogurt as part of a “gut-friendly” diet. Research backs up their gut-balancing nature, but the direct impact on colon cancer risk is more nuanced.
A large study in 2025 looked at whether eating yogurt over many years is linked to colon cancer risk. Researchers followed more than 130,000 people for decades, tracking their diets and taking note of who later developed colon cancer. They also analyzed tumor samples to see whether a specific helpful bacteria (Bifidobacterium) was present.
The study showed that eating yogurt wasn’t linked to a lower risk of colon cancer overall, but people who ate two or more servings of yogurt per week had a 20%-40% lower risk of a specific type of colon cancer tumor that has Bifidobacterium in it.
What this means: Helpful bacteria from yogurt can help crowd out harmful microbes. It can also help reduce chronic inflammation, which is tied to cancer risk, and make substances that may protect cells from becoming cancerous.
Is Yogurt Actually Protective?
What’s important to understand about yogurt and colon cancer risk is that so far, studies like this one have only shown a link between yogurt and colon cancer protection, which is different from a cause-and-effect relationship, Jobin says.
Probiotics help keep your gut healthy in general. No one really disagrees with that, Jobin also says. “But when you try to attach a very specific function to what they’re doing, this is where things fall apart.”
For one thing, he says, when you introduce millions of bacteria from yogurt into your gut, it’s actually very hard for them to take hold. Your microbiome starts populating itself when you’re born, shapes itself over your lifetime through your diet and environment— and wants to stay that way.
They may stick around briefly and make helpful compounds, but any benefit is likely temporary, he says. You’d have to eat yogurt consistently and repeatedly over an extended period to have any kind of effect.
Credit: webmd
