| Yogurt and other fermented foods have long been found to help improve gut health and fight inflammation. Now research by Mass General Brigham published in the journal Gut Microbes shows regular yogurt consumption can reduce the risk of certain types of colorectal cancer tumors through changes in the gut microbiome. Bifidobacterium is a healthy bacterium found in both yogurt and people’s intestines where it helps digest fiber, prevent infections and produces important compounds such as B vitamins. Another benefit is it also suppresses colorectal cancer. Bifidobacterium can be found in the tissue of some colorectal tumors, though it is not thought to cause cancer in any way. The researchers used data collected in two ongoing US studies from over 170,000 participants, including information on their demographics, lifestyles, medical histories and disease outcomes. The survey also included questions about their yogurt consumption. The researchers then cross referenced the responses with medical records and death certificates to calculate the association between each person’s long-term yogurt-eating habits and incidences of colorectal cancer. The findings showed that people who had eaten at least two servings of yogurt a week appear to have a lower risk of getting the type of colorectal cancer that contains Bifidobacterium. The study did not find however that yogurt intake reduces a person’s risk of getting general colorectal cancer without Bifidobacterium. Just over 30% of the cases examined in the research had Bifidobacterium in the cancer tissue. “This paper adds to the growing evidence that illustrates the connection between diet, the gut microbiome, and risk of colorectal cancer,” co-author Andrew T Chan, professor of Medicine at Harvard Medical School, said. “It provides an additional avenue for us to investigate the specific role of these factors in the risk of colorectal cancer among young people.” Driven by consumers’ increasing interest in healthy diets and more sustainable lifestyles, the global market for fermented foods, including yogurt, has surged in recent years. It was valued at over $500 billion in 2023 and estimated to grow 5.6% per year over the decade to come. Asian nations are the biggest consumers with over a third of the market share, thanks to the fact that fermented foods — from kimchi to kombucha to miso — have profound cultural roots across the region. Although such foods and drinks are generally positive for your health, the study’s co-author Shuji Ogino, a professor of pathology at Harvard T.H. Chan School of Public Health, warned that the companies that produce them sometimes overstate their benefits. Taking yogurt as an example, he told me brands that add a lot of sugar into fermented products often mislead consumers into believing their products are good for health, but are actually more dangerous. “They put out lot of commercials (about health benefits) without any evidence,” he said. “Sugar’s impact is much greater. If you eat yogurt with sugar in it, it may be more likely to have a bad effect than a good one.” — Karoline Kan | 
