Are Probiotics the New Frontier in Weight Loss?
Lately, there's been a lot of attention focused on the human gut and the community of friendly bacteria that live there. We used to largely ignore the bacteria that live naturally in the body. Few of us ever gave these invisible creatures a thought. But that time is past. In recent years, it's become increasingly clear that we ignore these little critters at our peril. That's because they are a living part of us. And they play a much bigger and more complex role in virtually every aspect of health than we ever imagined.
The complex, diverse communities of bacteria living in the gut—collectively known as the gut microbiome—influence everything from the immune system, to mood, to the nutrients we extract from our food. And now, say researchers, we know that certain microbes can even influence body weight. Gut bacteria communicate with the body to regulate weight gain, say scientists, and even influence your cholesterol levels.
The implications are profound. Foods that contain living gut-friendly bacteria (probiotics) have long been recognized as healthful. Think yogurt, kefir, kombucha, and other fermented foods. More recently, experts have shown that the link between a whole-foods diet and health may have plenty to do with the "prebiotic" substances these foods supply. Prebiotics are substances such as indigestible fiber, which provide a feast to keep gut bacteria happy and healthy. So not only is it important to cultivate a healthy gut biome, it's also important to keep feeding it—and yourself—whole plant foods to keep things humming along.
It also underscores the importance of taking steps to recolonize your gut with friendly probiotics whenever you're forced to take broad-spectrum antibiotics. These drugs can save lives, but in the past doctors have ignored a potential side effect: they can kill off helpful gut bacteria, too. It's like throwing the baby out with the bathwater. You cure an infection, but set yourself up for even worse problems—such as infection with the intestinal bug, c. difficile—by upsetting the balance of friendly bacteria living in the gut and elsewhere.
S. A. Joyce, J. MacSharry, P. G. Casey, M. Kinsella, E. F. Murphy, F. Shanahan, C. Hill, C. G. M. Gahan. Regulation of host weight gain and lipid metabolism by bacterial bile acid modification in the gut. Proceedings of the National Academy of Sciences, 2014; DOI: 10.1073/pnas.1323599111