Every hug gives your body a small dose of oxytocin, the neurotransmitter associated with love, intimacy, and lots of other good stuff. Just in case you needed another excuse to snuggle up, a new study has shown how cuddling infants during their early years could have a deeply profound effect on their biology later in life.
Recent research from the University of British Columbia (UBC) shows that the amount of hugging a child receives as an infant can influence epigenetic changes in at least five areas of their DNA, including areas related to the immune system and metabolism. Infants who had experienced less close physical contact in their first weeks of life were also shown to have a molecular profile in their cells that was underdeveloped for their age.
Previous work has found a similar phenomenon in rodents, but this is the first study to investigate how humans could also be affected by close contact and affection in early life.
“In children, we think slower epigenetic aging could reflect less favorable developmental progress,” Michael Kobor, a professor at UBC's Department of Medical Genetics, said in a statement.
The study, recently published in the journal Development and Psychopathology, asked the parents of 94 babies to keep a diary of their infants’ behavior, as well as their touching and cuddling habits, for the first 5 weeks of postnatal care. Four to five years later, they then sampled the DNA of these same children.
They then looked out for the epigenetic process of DNA methylation. This process works a bit like a dimmer switch to control how active a gene is. Epigenetics – literally meaning "on top of" genetics – explains how the extent of methylation can be affected by environmental influences, especially in childhood.
According to their findings, there were consistent differences in the extent of methylation at five specific DNA sites between the kids who had experienced a high level of contact and those who had not. In particular, one of these sites is known to play a role in the immune system and another influences metabolism.
It’s still early days for this research, however, the scientists on the project hope to follow these subjects to further learn about how our early experience, particularly snuggling and cuddling, can deeply affect our biology and our lives.
“We plan to follow up on whether the ‘biological immaturity’ we saw in these children carries broad implications for their health, especially their psychological development,” said lead author Sarah Moore, a postdoctoral fellow. “If further research confirms this initial finding, it will underscore the importance of providing physical contact, especially for distressed infants.”
So, the take away from this story: hug more.