Will happiness improve your health

Recent research has shown a correlation between happiness and good physical health. They often go hand-in-hand. Scientific studies have shown that happiness can make our hearts healthier, our immune systems stronger, and our lives longer.

According to the Greater Good Science Center, research has also uncovered a link between happiness and heart health, including heart rate variability, which refers to the time interval between heartbeats and risk for various diseases. In this study, researchers monitored 76 patients suspected to have coronary artery disease. The participants who rated themselves as happiest on the day their hearts were tested had a healthier pattern of heart rate variability on that day. It has also been found that happiness predicts lower heart rate and blood pressure. Participants rated their happiness over 30 times in one day and then again three years later. The initially happiest participants had a lower heart rate on follow-up (about six beats slower per minute), and the happiest participants during the follow-up had better blood pressure.

Research is now finding a link between happiness and a stronger immune system. According to the Greater Good Science Center, a 2003 study used 350 adults who volunteered to get exposed to the common cold. Before exposure, researchers called them six times in two weeks and asked how much they had experienced nine positive emotions that day. After five days of quarantine, the participants with the most positive emotions were less likely to have developed a cold. This same concept was applied to a 2006 study with those who were vaccinated with Hepatitis B. The high in positive emotion participants were nearly twice as likely to have a high antibody response to the vaccine.

Stress is upsetting on a psychological level and triggers biological changes in our hormones and blood pressure. Happiness seems to temper these effects, or at least help us recover more quickly. According to the Greater Good Science Center, these same studies stated the happiest participants had 23 percent lower levels of the stress hormone cortisol than the least happy participants. Another indicator of stress is the level of a blood-clotting protein that increases after stress, which was 12 times lower.

Research also states happiness can combat aches and pains, along with disease and disability. According to the Greater Good Science Center, in a 2008 study of nearly 10,000 Australians, participants who reported being happy and satisfied with life most or all of the time were about 1.5 times less likely to have long-term health conditions two years later. Another study in the same year found that women with breast cancer recalled being less happy and optimistic before their diagnosis than women without breast cancer, suggesting that happiness and optimism may be protective against the disease.

Overall, happiness and health have been anecdotally linked in the past (ex: "laughter is the best medicine"), but research backs up what many people have instinctively assumed all along: that happiness and health really are connected, and that one's level of happiness really can impact the level of one's health.