We often tend to associate smiling as the result of a positive event or mood. But research demonstrates that the act of smiling, in and【C1】______itself, can be the catalyst for joy. Wonderful things, ranging from an【C2】______mood to a better relationship, can be the result of the【C3】______act of smiling. Even better, it is a tool that is free, easy and always available. Even when you arent feeling happy, smile can help【C4】______your mood. Darwin hypothesized, back in 1872, that making changes in our【C5】______expressions can influence our【C6】______experience, something he called facial feedback response theory. Psychological research has【C7】______Darwin s assertion that expressions do not just result from moods, but actually influence them. Smiling more may actually【C8】______your lifespan. Research indicates that smiling may improve heart health by【C9】______heart rate after stressful events. So,【C10】______smiling to your health regime of eating well, getting enough sleep and exercising may just add【C11】______years to your life. People who smile more tend to be more【C12】______, joyful and emotionally stable which lends itself to healthier relationships, and thus have longer and more successful【C13】______. An interesting study published in 2009 found a correlation between smiles in photographs and divorce rates. The larger the smile, the【C14】______likely divorce was later in life.【C15】______, those with the smallest smiles or no smiles, were five times more likely to be divorced. When Mother Teresa said 'Every time you smile at someone, it is ... a【C16】______to that person, a beautiful thing', she was right. One study【C17】______by Hewlett Packard found that seeing anothers smile stimulated the heart and【C18】______more so than eating chocolate or receiving money. This was particularly true【C19】______viewing the smile of a child. Additionally, research has demonstrated smiling may actually be easily diffused. Research published in the Scandinavian Journal of Psychology examined mimicry, the tendency to mimic the emotional expressions of those around us, and found that it is actually hard to【C20】______when someone else is smiling. 【C1】