14. Insulinomas
Insulinomas tumors make, you guessed it–insulin (You may have started to notice a theme with the name and the corresponding chemical corruption). The increase in insulin can cause the body to suffer from effects associated with low blood sugar such as weakness, confusion, rapid heartbeat, and sweating. Having low blood sugar can cause some serious complications and when your body is overproducing insulin, it can really take a toll on your health.