Updated on January 23, 2023.
Who doesn’t want to feel happy? A good mood may put a spring in your step—and there’s a growing body of evidence suggesting that happiness may do even more for the body by protecting your immune system, aiding heart health, and boosting disease-fighting genes. But it’s not just any type of happiness—the source of your joy makes all the difference.
A 2013 study published in the Proceedings of the National Academy of Sciences was one of the first to examine the effects of two different kinds of happiness on the human genome: eudaimonic well-being (happiness linked to a sense of purpose in life) and hedonic well-being (happiness linked to pleasure). The study looked at the effects of these two types of happiness on inflammation, along with the expression of antiviral and antibody genes—all essential to the body’s ability to fight off bacteria and viruses.
The researchers found that those who have a deep sense of purpose and meaning in life had lower levels of inflammation and stronger expression of antiviral and antibody genes. But those high on hedonic happiness saw the opposite effect: Their levels of inflammatory genes were higher, while their expression of antibody and antiviral genes were lower.
"What this study tells us is that doing good and feeling good have very different effects on the human genome, even though they generate similar levels of positive emotion,” says Steven Cole, PhD, a professor of medicine at UCLA. He notes that participants had similar feelings of happiness, no matter which group they fell into.
Happiness and inflammation, immunity, and disease resistance
More recent studies continue to reveal a link between happiness and good health. A 2021 study published in the Journal of Affective Disorders showed that there is a link between inflammation and depression. In fact, it was found that people who were depressed showed higher circulating levels of interleukin-6 (IL-6), one of the main markers of inflammation in the body. This suggests that there is increased inflammation in the brain.
In that same study, researchers found a connection between levels of inflammation and the ability to process emotions, suggesting that those who had higher levels of inflammation were less happy and less able to effectively deal with their emotions. The body perceives this chronic inflammation as a consistent threat, leading to increased feelings of depression.
A 2019 study published in the Annals of Behavioral Medicine looked at the link between happiness, inflammation, and disease resistance, specifically for individuals living with type 2 diabetes. The researchers examined data from 140 people aged 50 to 75 and found that daily happiness was tied to significantly lower levels of IL-6 before and after taking stress tests.
There are plenty of other benefits, too. A 2017 comprehensive review published in Applied Psychology: Health and Well-Being, uncovered a whole host of positive associations between happiness and life satisfaction (called “subjective well-being”) and benefits to the heart, immune system, hormones, aging process, and even wound healing.
These researchers noted that happier people are more likely to have improved body functions and a healthier stress response, and ultimately take better care of themselves, leading to overall health and longevity. Four key areas were discussed in the study:
- Happier people seem to have less inflammation and better immune functioning. Better immune functioning, in turn, leads to healthier people who likely don’t get sick as frequently.
- Chronic stress is not good for the body and can lead to chronic diseases in the long-term. For example, if your cortisol levels are consistently high, your insulin levels may be affected. This, in turn, can lead to the development of disease. A negative mood has also been shown to make blood glucose levels harder to regulate the next day.
- Happiness affects your DNA, because of its effect on telomere length. Telomeres are small caps on the ends of your DNA strands, and the shorter they are, the worse your overall health. Short and/or degraded telomeres are linked to higher rates of disease, such as type 2 diabetes and certain cancers.
- Lastly, the researchers noted there may be a connection between happiness and wound healing. Because wound healing requires many different systems in the body to work together, these processes work most efficiently when people are healthier. Happier, less stressed people tend to heal more effectively. This is especially important for people at risk of serious infection or illness, as delayed wound healing can cause complications.
Overall, the link between happiness and health is becoming more and more clear. It’s a great topic for further consideration and study, and what could be better than happier, healthier people?
