Gut Bacteria at Older Age



The Scientific American has an article that says our gut bacteria change as we get older and are linked to diseases, including cardiovascular disease and type 2 diabetes.

According to a study published in Cell Reports, researchers discovered that bacterial samples taken from intestine were linked to older age with changes in bacterial populations. Older people had higher level of bacteria from the families Enterococcaceae, Lactobacillaceae, Enterobacteriaceae and genus Bacteroides, that are known to cause diseases in human.

Overall bacteria diversity also declined as people got older, going down as people headed towards age 80. Low diversity has been linked to health problems too. Studies have found a relationship between low bacterial diversity and Crohn’s disease, irritable bowel syndrome and colorectal cancer, among other conditions.

Because the new study only found associations, it does not prove that these changes cause aging. Instead, gut bacteria might change after people get older. “We really don’t know the chicken or the egg here, but we need to find out”. He hopes to tease out answers in future studies, including additional experiments that transplant “older” microbiomes into young animals to see if it makes them age faster or become ill. It would also be interesting, he says, to study the microbiomes of healthy centenarians and identify differences that could play a role in healthy aging.

– Mark Pimentel, Co-author of the Cell Reports study

Heidi J. Zapata, an infectious disease specialist and immunologist at the Yale School of Medicine, encourages “people to also be judicious in their use of antibiotics—to avoid taking them when they aren’t needed, and to take targeted antibiotics rather than drugs that kill off a broad array of bacteria. After treatment with broad-spectrum antibiotics, gut bacteria tend to grow back with less diversity, she says, and more unhealthy kinds of bacteria can thrive. An unbalanced microbiota can definitely lead to infections and disease. It is important to understand these changes that happen as we get older to try to see if we can improve the aging process.”