How are hemorrhoids caused by it? The reasons are many, mainly the following: a, anatomical reasons: anus is located in the lower part of the body, people more upright, so that hemorrhoids on the vein under maximum pressure, coupled with the role of gravity and gravity, so that hemorrhoidal venous blood reflux difficulties, over time, varicose into hemorrhoids. The anorectal vein runs diagonally through the rectal muscle layer and sphincter, and when the muscle contracts or defecates, the abdominal pressure increases and the fecal pressure prevents the blood from flowing back, causing the veins to varicose into hemorrhoids, because the hemorrhoid plexus at the end of the rectum is located in the lax submucosal space, which is easy to stagnate and become angry. So some people say that hemorrhoids are a disease unique to upright animals. The genetic relationship: hemorrhoids have a hereditary, there is still debate, but from the census data and clinical history shows that most patients, their parents are suffering from hemorrhoids, the parents generation of vascular tissue elasticity fragile can be inherited to the next generation, the vein wall congenital weakness, resistance is reduced, can not tolerate intravascular pressure, and therefore gradually dilated. Third, the relationship of occupation: in the clinic we found that people engaged in a certain occupation, than other occupations are prone to hemorrhoids, such as car drivers, hairdressers, etc., because they work in a relatively fixed position, often sitting or often standing, so that the blood circulation of local blood vessels is blocked, venous reflux is affected, easy to produce hemorrhoids. There are also patients who often suffer from hemorrhoids because of excessive fatigue, because, when the body is fatigued, the resistance of the blood vessel wall is correspondingly weakened, so once the pressure on the blood vessel wall increases, it is easy to break and bleed. The actual fact is that you can find a lot of people who are not able to get a good deal on a lot of things. This is because spicy food is generally not easily digested and absorbed in the digestive tract, stimulating the mucosa and causing venous congestion in the anorectal area. Alcohol can cause hemorrhoidal venous congestion in addition to weakening the resistance of the blood vessel wall. Fifth, the anus infection: hemorrhoid plexus first due to acute and chronic infection and inflammation, the elastic tissue of the vein wall gradually fibrosis and weakness, lack of resistance, and expand varicose, plus other reasons, so that varicose veins gradually aggravate, generating hemorrhoids. Six, other such as abdominal tumor, liver cirrhosis, prostate hypertrophy, pregnancy, etc. can increase intra-abdominal pressure, affecting the hemorrhoidal venous reflux, which can also produce hemorrhoids over time.