A baby a few months old reaches out a hand, looks at the parent facing him and waits for a response. Sometimes it comes immediately — a look, a smile, a soothing sound. Sometimes it is delayed. Sometimes it is barely there at all. Who would imagine that such quiet, everyday moments carry meaning beyond the instant itself? It turns out they matter a great deal.
Early parent-child interactions, according to a large longitudinal study that followed hundreds of families from infancy through school age, are linked years later to physiological measures of health, including inflammation, blood sugar and metabolic health. In other words, the body remembers.
4 View gallery
Researchers found that the quality of early parental relationships was correlated with various physiological measures years later
(Photo: shutterstock)
The study tracked 292 American heterosexual families with their first child over several years, from infancy through school age. “This is a relatively unique study because it is among the first to examine not only the relationship between mother and child, which most studies focus on, but also father and child, and the combined parental dynamic — father, mother and child,” explains Yarden Gabbay, a clinical psychologist.
As part of the research, children were followed over time with three main measurement points: at 10 months, at 24 months and again when they reached age 7. The researchers focused primarily on three areas. “They filmed interactions between parents and children and then examined the dynamics between the parents themselves — both situations of competition for the child’s attention and situations of avoidance, disengagement or lack of cooperation,” Gabbay says. “The goal was to assess not only the quality of the parent-child relationship, but also the broader family context in which that relationship exists.”
At a later stage, the behavioral data were linked to medical measures. “When the children reached school age, the researchers examined blood markers indicating inflammatory status and metabolism, including measures such as cholesterol,” explains Dr. Jonathan Dvash, a clinical psychologist, supervisor and deputy national chief psychologist at Clalit Health Services. Those medical findings were then compared with the interactions documented during the children’s early years. “They examined the emotional-behavioral component and compared it with medical tests conducted when the children were 7,” Gabbay adds.
Dr. Jonathan Dvash: 'There is extensive evidence that early relationships have a significant impact on the course of children’s lives. We take this into account when we design intervention systems that aim to provide support at very early stages, because childhood time is not adult time, and interventions at early stages often have a very large effect later on'
By the end of the study, researchers found that the quality of early parental relationships was correlated with various physiological measures years later, particularly in the father-son relationship. “What is interesting in this study is not only what happens between parent and child, but also what happens between the parents around the child,” Dr. Dvash says. “When fathers were more sensitive and involved already in infancy, later on — around age 2 — there was less problematic parental dynamics around the child, such as competition for attention or withdrawal and lack of cooperation.”
Those patterns were later linked to two blood markers in the children: an inflammation marker, C-reactive protein, and a marker related to long-term blood sugar regulation, HbA1c. “Among mothers, in this model and with the measures examined, the association did not reach statistical significance. That does not mean mothers are less important, but that in these data the same link was not identified in the same way. It is also important to say honestly: The association found among fathers was not huge, but it was statistically significant.”
Gabay also emphasizes that the findings do not suggest paternal superiority. “It’s not that fathers carry more weight,” she says. “The researchers are not arguing that mothers are less influential on a child’s health. They propose several possible explanations. One is that children are accustomed to high maternal involvement, so even less optimal patterns may be perceived as routine rather than stressful. In addition, in this sample, mothers were generally very sensitive and involved, making it harder to detect differences.”
Dr. Jonathan DvashBy contrast, she explains, “When a father withdraws or competes within the parental dynamic, it can affect the atmosphere at home and increase stress, which directly impacts the child’s stress levels. When a father is sensitive, it is experienced as especially positive — not because the father is more important, but because among fathers, being positive, sensitive, attentive and supportive may be more salient.”
Dr. Dvash also cautions against a simplistic interpretation. “This could create a false impression that fathers’ behavior is more important,” he says. “It’s important to understand that the study examined fathers and mothers, but not roles. These were heterosexual, middle- to upper-middle-class families, like many studies, and it is difficult to generalize that the primary caregiving role was held by the mother. In addition, there was no direct comparison between mothers and fathers. The comparisons were between mothers and mothers and between fathers and fathers.
Yarden GabbayPhoto: Ben Itzhaki“Mothers typically perform this role more consistently day to day. Among fathers, there is much greater variability — some are very involved, others much less. Because of those differences, statistical significance may have emerged. It is also important to note that this is a correlational study, not one of causation. It examined whether there is an association between certain behaviors and these markers, but causality cannot be inferred.”
Not paternal advantage, but the family dynamic
The link between emotional experiences and physical health is not a new idea. “In the end, it’s all deeply connected,” Gabbay says. “The way I think affects my mental state and, naturally, affects my body at a biological level. Emotional states such as depression, anxiety and chronic stress directly influence the body’s regulatory systems, especially the autonomic nervous system and the immune system.”
As an example, she points to prolonged stress. “It can raise stress hormones, affect inflammatory processes and everything related to risk for heart disease and pain. Autoimmune diseases, where the body attacks itself, are also connected.” When it comes to children, she stresses, the impact may be even deeper. “The people who raise us, the figures who care for us — whether they are a mother and father, two fathers, two mothers, a grandparent — how they treat us, whether they give us enough warmth, engage with us playfully, play with us and help us develop our abilities as toddlers, all of this affects our bodies later on.”
Yarden Gabbay: 'When a father withdraws or competes within the parental dynamic, it can affect the atmosphere at home and increase tension, which directly impacts the child’s stress. When a father is sensitive, it is experienced as much more positive — not because the father is more important, but because with fathers, positive, sensitive, attentive and supportive behavior tends to be more salient'
Dr. Dvash notes that the connection between early interactions and later health is not surprising to researchers. “There is extensive knowledge showing that early relationships have a significant impact on children’s later lives,” he says. “We take this very seriously when building intervention systems that aim to respond already at early stages, because childhood time is not adult time. Early interventions often have a very large downstream effect. “We have long known from a growing body of research that early interactions affect both emotional-mental aspects and physical health. This study adds another layer to that understanding.”
As for the study’s implications, Dr. Dvash says the key is not a hierarchy between parents, but a systemic perspective. “I don’t think the takeaway is that fathers have more influence, but that working with fathers can be very important,” he says. “As a system, we need to try to prevent future difficulties, both mental and physical. We need to think about how to intervene and with whom, and we know that involving fathers in treatment is critical.”
From that perspective, the professional approach does not focus on only one parent. “Even if the father is less involved in raising the child, this is an example of how the degree of his involvement matters a great deal. It is very clear to us that we need him. We need to involve fathers in treatment, which is why in many cases we insist that both parents attend therapy and parent guidance to create change.
“Very recently, Clalit launched a parental counseling service that focuses precisely on preventing health problems from developing in primary care settings. No one teaches us how to be parents, and this is part of the way to intervene and prevent future illness.”
Gabbay concludes that the study’s bottom line is clear, but requires careful reading. “The way you behave toward your children from very early stages of life, and the way you manage family and parental dynamics, is linked to better physiological outcomes in children.”
At the same time, she emphasizes, the findings should not be interpreted narrowly. “It’s important to add — certainly in 2026 — that this does not mean that only a mother-father relationship is ideal. Many studies show good and positive mental health in families of different structures, whether co-parenting, single-parent or same-sex families. There should be no interpretation that a father is better than a mother, or that a father is required for a child to be healthy. It’s important that no such conclusion is drawn.”