• Yogurt enriched with live cultures is believed to guard against various illnesses, including certain types of cancer.
• While experts are still exploring the exact mechanisms, it is thought that yogurt’s impact on the gut microbiome may play a crucial role.
• A recent study indicates that regular consumption of ‘live’ yogurt could diminish the risk of certain colorectal cancers.
• Findings revealed that individuals who consumed two or more servings of yogurt weekly had a 20% lower incidence of bowel tumors that tested positive for Bifidobacterium.

Colorectal cancer ranks as the third most prevalent cancer globally, accounting for over 10% of all cancer cases, according to the World Health Organization (WHO) reporting.

Factors such as physical inactivity, smoking, obesity, excessive alcohol intake, a diet high in processed meats, and low consumption of fruits and vegetables can elevate the risk of colorectal cancer.

A diet rich in fiber, laden with fresh produce, whole grains, and dairy products, is associated with a decreased risk of colorectal cancer.

Research led by Mass General Brigham and published in the journal Gut Microbes has further illuminated the potential advantages of yogurt in lowering the risk of certain colorectal cancers.

The study found that participants consuming two or more servings of live-culture yogurt each week showed a 20% reduction in the likelihood of developing colorectal tumors associated with the Bifidobacterium strain, commonly present in the gut.

Gemma Balmer-Kemp, PhD, Head of Research at Cancer Research UK’s Cancer Grand Challenges, a supporter of the study, shared insights with Medical News Today:

“The role of endogenous bacterial species is increasingly recognized for their potential health benefits. This study adds to the evidence supporting the protective effects of yogurt containing live cultures against certain variants of colorectal cancer.”

“While this study indicates a link between long-term yogurt consumption and reduced rates of proximal colorectal cancer that is Bifidobacterium-positive, further research is needed to elucidate whether Bifidobacterium plays a causal role and the underlying mechanisms,” she elaborated.

“Live” yogurts contain multiple bacterial strains. Commonly, Lactobacillus bulgaricus and Streptococcus thermophiles are utilized to ferment milk into yogurt, with other beneficial bacterial strains referred to as probiotics possibly being included.

To assess the relationship between yogurt consumption and colorectal cancer risk, the researchers analyzed data from the Nurses’ Health Study and the Health Professionals Follow-up Study, monitoring over 100,000 female nurses since 1976 and 51,000 male health professionals since 1986.

Participants frequently complete questionnaires regarding lifestyle, dietary habits, and health, including inquiries about the intake of plain and flavored yogurts alongside other dairy products. For those diagnosed with colorectal cancer, researchers examined tissue samples for Bifidobacterium DNA.

Among the cohort, 3,079 individuals developed colorectal cancer; tissue data related to Bifidobacterium was available for 1,121 of these cases, showing that 775 had Bifidobacterium-negative colorectal cancer, while 346 were Bifidobacterium-positive.

While the study did not observe a significant correlation between long-term yogurt consumption and the overall occurrence of colorectal cancer, it did find that those who consumed more yogurt had a 20% lower incidence of tumors that tested positive for Bifidobacterium.

Kelsey Costa, MS, RDN, a dietitian and owner of Impactful Nutrition, although not part of the study, provided insights to MNT regarding the role of Bifidobacterium in colorectal cancer:

“This research does not imply that yogurt decreases Bifidobacterium levels in the gut. On the contrary, it underscores the significance of Bifidobacterium, which is beneficial for producing short-chain fatty acids (SCFA) and possesses anti-cancer effects through antioxidant, anti-inflammatory, and immune-enhancing properties,” she noted.

She explained: “The presence of Bifidobacterium in tumor tissue might indicate compromised gut barrier function. Studies have shown that Bifidobacterium can enhance gut barrier integrity by lowering harmful inflammatory proteins such as tumor necrosis factor and interleukin 6.”

“Yogurt could contribute to reinforcing the gut barrier, thereby supporting Bifidobacterium’s role in curbing the growth of Bifidobacterium-positive tumors, rather than reducing Bifidobacterium levels itself,” she elaborated.

The observational nature of the study means that its findings reflect correlation rather than causation, as Balmer-Kemp explained:

“This research implies that yogurt consumption over an extended period may offer protection against this specific subtype of colorectal cancer, potentially mediated through alterations in the gut microbiome. The identified bacterial strain, Bifidobacterium, is both present in yogurt and in the human gut.”

“Various subtypes of Bifidobacterium exist within the human gut, each fulfilling different functions, including carbohydrate metabolism. This study did not delve into the causal relationship between the microbiome, Bifidobacterium, or any underlying mechanisms,” she informed MNT.

While natural yogurts with live cultures are a valuable addition to a nutritious diet, not all varieties are beneficial. Flavored and fruit yogurts often contain excessive added sugars and other unhealthy components.

In contrast, plain, live yogurts provide a wealth of nutrients, including calcium, phosphorus, potassium, vitamin A, B vitamins, protein, and healthy fats. They also serve as a rich source of probiotics—living microorganisms that provide health advantages when consumed in adequate amounts.

Research indicates that these probiotics might bolster the immune system and enhance overall health.

Certain yogurt types might offer additional advantages. For instance, traditional full-fat Greek yogurt can promote bone health, aid in muscle growth, and potentially reduce the risk of conditions like high blood pressure, type 2 diabetes, and certain mental health disorders.

Furthermore, while consuming large quantities of regular milk (approximately four glasses daily) may elevate heart disease risk, fermented milk products like yogurt and kefir provide similar nutritional benefits with no known negative impact on cardiovascular health.

Thus, this recent study supports the idea that incorporating yogurt into your diet may help lower your colorectal cancer risk. It’s essential to choose live, natural yogurt to maximize health benefits.

According to Costa, “Although specific recommendations for yogurt consumption frequency are unavailable, integrating a standard 1-cup serving into your meals a few times weekly or even daily could yield positive effects on your gut microbiome.”

“If yogurt isn’t appealing, consider other fermented foods such as coconut kefir, kimchi, miso, and sauerkraut, which also contain probiotics beneficial for gut health,” she suggested.