New research suggests that children with less family wealth tend to practice selfless concern for the wellbeing of others and may reap better physical and physiological health from it.

Researchers found that children as young as 4 years old can benefit from altruistic giving, a behavior that tends to be less common among kids from high-income families.

"The findings provide us with a new understanding of how children's altruistic behaviors, family wealth, and physiological health are intertwined," Jonas Miller, lead researcher of the study, said in a statement.

For the study, researchers recruited 74 toddlers, average age 4 years old. The researchers played with the children one by one and explained that they would earn tokens that they could trade for prizes at the end of their visit. Near the end of their visits, the children were given the chance to donate some or all of their prize tokens to fictitious sick children who weren't able to come to the lab.

They found that the children who sacrificed tokens to help sick kids showed greater vagal flexibility during the task, indicating better physiological regulation throughout.

"We usually think of altruism as coming at a cost to the giver, but our findings suggest that when children forgo self-gain to help people who are less fortunate, they may get something back in the form of higher vagal tone," Miller explained. "It means we might be wired from a young age to derive a sense of safety from providing care for others."

Based on their findings, researchers noted that because children from less wealthy families donated more tokens, they may get a helpful physiological boost from altruistic behavior. This boost might help to offset some of the physiological disadvantage associated with growing up in a lower-income household.

"Our findings suggest that fostering altruistic tendencies might be one path to promoting better health and well-being for all children," Miller concluded.

The findings are detailed in the journal Psychological Science.