A diet containing too much meat increases the risk of thrombosis or blood clotting, says a US study. The study also shows that a diet rich in fruit and vegetables reduces the risk of thrombosis, that often occurs in the deep veins in the legs. Eating fish once or more often a week reduces the risk of thrombosis by between 30 and 45 percent. The study was conducted by universities in the US and involved 15,000 adults who were examined over a period of 12 years. It becomes dangerous if the blood clot dislodges and travels to the lungs where it can cause an embolization, completely stopping the flow of blood.