One way is through mind-body practices, like meditation, which “have been shown to cultivate positive and happy immune cells,” he says. Research has linked meditation to reduced negative inflammatory activity, increased positive antiviral response, improved function of specific strains of immune cells, and higher antibody production.

But perhaps the most striking theory posed of meditation is that it could alter genetic material.

In recent years, a new field of study, known as mind-body genomics, has emerged. Among the most well-known researchers in this area are Nobel laureate Elizabeth Blackburn, a biochemist at the University of California, San Francisco, and her colleague, psychiatrist Elissa Epel. Through a series of studies, the two found that meditation could affect the ends of DNA known as the telomeres, which act as protective caps for genes. The longer the telomere, the greater the protection conferred for the DNA strand, and the longer that cell can survive.

And telomeres, like immune cells, seem to respond to emotional cues. Negative external conditions like chronic stress that reduce eudaimonic happiness may shorten telomere length, while stress-reducing activities like meditation may help to maintain it. “Telomeres are affected by many things, but they are directly affected by stress. So we can see how improvements in our mental health, through the practice of meditation, might be linked to improvements in our telomeres,” Epel explains. “They offer us a window and some insight into how we are living, and help us appreciate how what we do today can affect our health tomorrow.”

As the field of mind-body genomics matures, the focus is moving towards gaining a better understanding of not only how DNA could be structurally changed by meditation, but also whether meditation can alter DNA functionally, through changes in how genes are expressed. In one recent study, for example, meditation was linked to enhanced expression of genes associated with insulin secretion, telomere structure, and cellular energy and function, and decreased expression of genes linked to inflammation and stress. What’s more, blood samples collected during the study found that experienced meditators showed changes in their genetic activity after just one meditation session.

With around 20,000 genes in the human genome, Cole, Epel, and other researchers have just scratched the surface of the connection between our emotional and biological selves. “We are an ever-changing conglomeration of cells very much influenced by our experience of the world around us,” Cole says. “At the rate we’re going, we have more data than we can make sense of. It’s this process that helps us get closer to understanding the black box. Who knows? Maybe in the future we may be able to sequence our own genes.” Epel agrees: “We don’t yet have the technology to monitor our telomeres, but it’s coming.”

In the meantime, though, the lessons of mind-body genomics still apply. “The experience you have today will influence the molecular composition of your body for the next 80 days, because that’s how long the average protein synthesized in your body today will hang around in the future,” Cole says. “So plan your day accordingly.”

This and other quotes of Cole's have been updated for clarity and accuracy.

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