Updated: 11/12/2023 por Jennifer Delgado | Published: 15/04/2019
Hugs are a medicine for the soul. It is no coincidence that the family psychotherapist Virginia Satir said: “We need 4 hugs a day to survive, 8 hugs to keep us and 12 hugs to grow.”
The effects of hugs cross the psychological barrier and extend to the physical plane. This type of body contact decreases the level of cortisol, the stress hormone, and generates comforting sensations that help us feel better and relieve pain. Now it has been discovered that their presence – or absence – in early life could even affect the expression of DNA.
Physical contact is essential in childhood
Researchers at the University of British Columbia discovered that the effect of hugging babies and holding them in our arms lasts even at 4 years of age.
To reach these conclusions, researchers analyzed 94 healthy children of five weeks of age and asked their parents to keep a diary of the behavior of the children in which they recorded their sleep habits, feeding, and when they were restless or crying, as well as the amount of physical contact they maintained. When the children turned 4 and 5 years old, the researchers took samples of their DNA.
The team examined a biochemical modification called DNA methylation, in which parts of the chromosome are marked with small molecules of carbon and hydrogen. These molecules act as “attenuation switches” and help control the activity of each gene.
The degree of methylation and the part of the DNA where it occurs depends largely on external conditions, especially in childhood. In fact, these epigenetic patterns change predictably as we get older.
The scientists found methylation differences in 5 specific DNA zones among children who received hugs and those who did not. One of these changes plays an essential role in the functioning of the immune system and the other influences the metabolism.
The babies who experienced greater anguish during their first months of life and received less hugs and physical contact, showed an “epigenetic age” lower than what corresponded to their biological age. Its molecular profile was immature, which indicated that they were lagging biologically.
“We believe that a slower epigenetic aging may indicate an inability to thrive”, said Michael Kobor, a professor at the Department of Medical Genetics of the University of British Columbia.
In fact, previous studies have associated the discrepancy between epigenetic age and biological age to poor health. When methylation, a process that is part of a normal development and is essential for some key processes of the body occurs in later stages of life, the risk of developing abnormal and/or pathological processes increases, as revealed by researchers at University College London.
Although the long-term effects of this immature epigenetic profile in children are not known, there is a clear conclusion: babies need hugs, caresses and physical contact for their emotional and physical development.
Sources:
Moore, S. R. et. Al. (2017) Epigenetic correlates of neonatal contact in humans. Development and Psychopathology; 29 (05): 1517.
Jones, M. J. et. Al. (2015) DNA methylation and healthy human aging. Aging Cell; 14(6): 924–932.
Teschendorff, A.E. et. Al. (2012) Epigenetic variability in cells of normal cytology is associated with the risk of future morphological transformation. Genome Med; 4: 24.
Rodríguez, M. et. Al. (2004) Metilación del ADN: un fenómeno epigenético de importancia médica. Rev Invest Clín; 56(1): 56-71.
