By Paul A. Offit
Discussions about weight loss may soon take a dramatic turn. At issue will be the microbiome, a collection of bacteria that lines the intestine, nose, throat, skin, and genital tract.
Although people are blissfully unaware of its existence, humans have about 10 times more bacteria lining the surface of their bodies (about 100 trillion) than they have cells in their bodies (about 10 trillion). In many ways, we live in peace with our microbiome, which helps to digest food and balance glucose levels. But the microbiome has also been associated with various problems, including asthma, allergies, eczema, and diabetes. The microbiome also helps to store fat, which can lead to obesity.
Obesity isn’t a trivial problem—it affects life-expectancy, quality of life, and health-care costs. The problem is far more common than most people realize. More than 44 percent of the world’s population is obese; 300 million people are morbidly obese. In the United States, about 35 percent of the population battles obesity.
So how can you know whether you have a good microbiome or a bad microbiome?