Every time you eat a meal, you're not only feeding yourself, but the hundred trillion bacteria that thrive in your intestines. This colony of bacteria plays a huge role in health, and believe it or not, the bacteria in your gut influences your metabolism. Obesity once was a rarity, but the last few decades have seen an explosion of weight gain. Recent studies have shown obesity to be associated with a shift in the bacteria in the gut. Alterations in the gut bacteria can impact your metabolism. But How? Gut microbes alter the signalling pathways in the gut, effecting the inflammation pathway, encouraging insulin resistance (pre-disposing for diabetes) and depositing energy as fat storage.
Junk food & Your Gut
You are what you eat, and so are the bacteria that live in your intestines. A study in Nature magazine illustrated how incredibly fast (3-4 days) the human gut can change after a shift in what you eat. Imagine how junk food can effect your gut microbiota. Studies have shown that beneficial bacteria are in more abundance in a high fiber diet, and are drastically different with a western diet.
What Does This Mean For You?
Since all of those bugs in your intestine can be either helpful or harmful, it's important to reconsider what you are eating. Not only do we eat to ensure that we have the best health possible, but also to propagate a healthy microbiota. Eating a purely western diet--high in animal products, low in fiber, high in fats--encourages a completely different microbiome than one that is high in fiber, fruits and vegetables and low in processed food. The best mantra is to eat food with a purpose, on purpose. As for treats, they're just that--treats, and not all you eat.