Few other emotions can trump human reason like love. Love is an instinct like eating and drinking - primitive but vital. It is not romance but above all biology that brings two people together: we can identify the right partner for us by their scent, just as animals do. Recent research shows that the sense of smell, especially in women, has a significant influence on the choice of partner. Love can make wounds heal faster, lower your pulse rate and blood pressure and reduce anxiety and stress. But it can also make you sick and even kill you: "Broken Heart Syndrome” can be as dangerous as a heart attack.