With social development and improved quality of life, the number of obese people is also rising year by year, as early as 2016, China’s obese population has surpassed the United States in terms of number, jumping to the first in the world. But in fact, overweight weight not only affects the appearance of the body, but also leads to various health problems. Obesity increases the risk of joint inflammation, skin diseases, endocrine disorders, cardiovascular damage, tumors and many other conditions, but not only that, a Brazilian study found that obesity and type 2 diabetes patients are more likely to suffer from infectious diseases because obesity and diabetes affect the human immune system. Obesity and diabetes reduce the activity of a class of proteins in neutrophils in the body, resulting in an inadequate inflammatory response when pathogens are encountered, making the body less able to defend itself against pathogens. The damage of obesity to the immune system is reflected in the following aspects: First, weaken the immune response The immune system is composed of three parts, when the body suffers from pathogens, the innate immune system first fights back against the invaders; the adaptive immune system then produces antibodies to prevent the invaders from attacking in the future; at the same time, the body forms memory cells to help the immune system identify future pathogens. And at these three levels, because the whole immune system of obese people is damaged and inhibited, so their immune system response are very weak. Second, easy to infect Whether it is abrasion or surgical incision, fat people’s wounds are more likely to be infected, especially patients with severe obesity. Easy to get autoimmune diseases Because the body’s immune system is disrupted, obese people will be more likely to suffer from autoimmune diseases, such as rheumatoid arthritis, type 1 diabetes, Crohn’s disease and multiple sclerosis. Third, easy to get the flu in 2009 swept the global wave of influenza A (H1N1) epidemic, obesity has become a very obvious risk factors; compared with BMI in the normal range of people, BMI > 30 people die from the flu virus is 3.1 times more likely. Fourth, easy to get pneumonia because the accumulation of fat in the chest prevents the exchange of gas. At the same time, the fat in the abdomen pushes the diaphragm upward, limiting the expansion and contraction of the lungs. When a secretion enters the lungs, it can cause pneumonia. V. Reduce the effectiveness of the vaccine In some ways, the immune system of obese people is like the immune system of the elderly, so it does not respond well to the effectiveness of the flu vaccine. In addition, the effectiveness of hepatitis A, hepatitis B and tetanus vaccines is also reduced in obese people. Tips for friends, maintain the ideal weight, is absolutely in line with the health way, but also to choose a scientific way to reduce weight do not blindly try, for the health of those around you, as squarely as the epidemic obesity.