You may not be at the helm of your appetite control center. It could be the bacteria in your gut dictating what you want to eat, according to a review of studies by researchers at the University of New Mexico. The findings suggest that the array of different bacteria in the gut, called the microbiome, influences our food choices by releasing signaling molecules into our gut. The digestive tract is linked to the immune system, the endocrine system, and the nervous system, so those microbiome-generated molecules influence our physiologic and behavioral responses. Research shows that gut bacteria affect food choices by acting on the vagus nerve, changing taste receptors, producing toxins to make us feel bad, and by releasing chemical rewards to make us feel good when we eat what they want to feed on. For example, some bacteria prefer fat and others prefer sugar, so they release molecules that tweak our preferences for foods high in these substances. The researchers state that this relationship between the microbes in our gut and the rest of our body is a two-way street. We can influence the compatibility of these microscopic, single-celled house guests by what we consciously choose to eat, including foods rich in probiotics, prebiotics, and phytonutrients.
A study from King’s College London and Cornell University found that our genetic make-up influences whether we are fat or thin by shaping which types of microbes thrive in our body, and a study from the University of Illinois found that fiber alters gut bacteria in favor of weight loss and lower risk for disease.
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