CD14 gene knockdown can reduce the inflammatory state of mice caused by LPS; TLR4 gene knockout can also prevent obesity and insulin resistance caused by high‐fat diet, thereby reducing obesity.58, 59 Obesity is often a leading factor associated with type 2 diabetes mellitus (T2DM), so the above mentioned mechanisms of intestinal flora causing obesity can also increase the risk of T2DM. The gene discussed is TLR4; the disease is obesity due to melanocortin 4 receptor deficiency.