A specific type of bacterial toxin called endotoxin increases the likelihood you’ll be overweight.

The bacteria, fungi and other organisms in your intestines are collectively known as your microbiome. You have a lot of them living in your gut; they weigh approximately 3 pounds. Your gut bugs perform a number of important functions for you: they help with food digestion, vitamin production and they regulate the function of your immune system.

Interestingly, your microbiome has a big influence on your body weight. We know that when obese people are compared with thin people, there are huge differences in the composition of their gut bugs. Now researchers have discovered a culprit. Specific strains of gram negative bacteria produce a metabolic by-product called endotoxin (also known as lipopolysaccharide).

Endotoxin can be absorbed into your bloodstream, and having high levels in your blood can lead to health problems. Endotoxin is highly inflammatory to your body and is even capable of inducing a mild fever. This is commonly experienced as being heat intolerant and feeling excessively hot at night.

High levels of endotoxin in your blood can lead to weight gain by triggering insulin resistance. This can cause high blood insulin levels and metabolic syndrome (syndrome X). Interestingly, the plant compound berberine is able to bind to endotoxin and prevent its absorption into the bloodstream. This is one of the reasons why berberine is so great for helping with weight loss.

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