The gut is home to over 100 trillion bacteria cells. That’s ten times the number of cells that make up your entire body. Collectively, your gut bacteria weigh about four pounds. That’s the weight of a brick. Although you might not think much about your gut bacteria, they have a profound effect on both your digestive health, and the health of the rest of your body.

An exciting area of gut bacteria research is the investigation of the effects of gut bacteria on obesity and obesity-related conditions. I’ve blogged on the topic more than once. Obese individuals have been found to have a different gut microbial composition than their lean counterparts. The gut microbes associated in obese individuals may metabolize food differently than those found in lean individuals, resulting in the accumulation of body fat.

A recent study builds on the current research with the discovery that differences in gut microbes may be related to behavioral changes and increased food intake, and may influence our ability to properly sense and respond to a meal. The study, published in the FASEB Journal, expands the picture of our gut bacteria’s ability to affect weight gain. That gut bacteria may affect behavior related to how we eat takes the gut connection to obesity to a whole new level.

Another study presented at the International Liver Congress 2012 highlights the gut microbiota’s contribution towards the development of diabetes and non-alcoholic fatty liver disease (NAFLD). The researchers used an animal model in which they transplanted gut bacteria of either healthy mice or mice with insulin resistance and fatty liver, into germ-free mice (mice lacking gut bacteria). The mice who received gut bacteria from insulin resistant, fatty liver mice developed more insulin resistance and fatty liver than the mice who received gut bacteria from healthy mice. Mice who received gut bacteria from healthy mice were protected against these metabolic conditions.

These studies are paving the way towards a more complete understanding of the effects that gut bacteria have on our health. In the meantime, support your gut bacterial balance by optimizing your diet (plenty of fruits and vegetables, omega-3s, and fiber), reducing stress, and taking probiotics.