A Few Good Bugs: The Surprising Health Benefits of Bacteria

Methé couldn't be more right. When I received my microbiome results, I was disappointed by the lack of information about the bugs milling around in my body. In fairness to uBiome, they simply didn't have many other samples to compare mine with yet. They were able to tell me what percentage of my bugs fell into four basic categories of bacteria, including firmicutes and proteobacteria. And based on what they know so far, the scientists concluded that my levels appeared to be within a healthy range. (High levels of firmicutes may point to an increase in a protein associated with inflammatory conditions like heart disease; lots of proteobacteria may be a sign of type 2 diabetes.)

What they couldn't tell me was how my levels of certain types of bacteria compared with those of people who are obese or have cancer—the stuff I really wanted to know. But these are exactly the sort of correlations researchers are starting to make. And that's where things get exciting.

Manipulating the Microbiome

We've long known that if your body's natural balance of bacteria is upset (whether by a course of antibiotics or an awful case of food poisoning), you can end up with diarrhea. But new research suggests that colon cancer, which kills about 50,000 people each year, could be another, more dire, outcome. Studies have found that patients with colorectal cancer have high levels of E. coli bacteria, the infamous fecal germs guilty of causing major outbreaks of food poisoning. While scientists are still studying the exact role bacteria play in the cancer's development (does an overgrowth of E. coli cause cancer? does cancer cause the overgrowth?), one thing's for sure: Increased levels of the bacteria signal trouble. The hope is that by monitoring bacteria levels in a person at risk of disease—in this case, colon cancer, but potentially diabetes, say, or rheumatoid arthritis—doctors will catch these conditions in their very early stages, and may be able to treat them simply by correcting the bacterial imbalance.

The same may be true for fighting obesity. In a study at New York University, children who had been given antibiotics before the age of 6 months were 22 percent more likely to become overweight preschoolers than kids who hadn't. In another study, rodents started packing on fat shortly after receiving antibiotics—gaining about 10 to 15 percent more than their unmedicated friends. Researchers believe the drugs altered the mix of bacteria, leading to a higher concentration of bugs that can extract more calories from food.