Weight gain occurs when a person’s energy expenditure is less than what he consumes, in a nutshell: if we don’t spend what we consume, it accumulates in the form of fat. This maxim is well known, but what is ignored is that on average, almost half of the body’s energy is used by the brain during the early years of childhood. And glucose is a very fast source for energy.
According to a new study, published in Proceedings of the National Academy of Sciences (PNAS) , a team led by Christopher Kuzawa , points out that this variation in the energy needs of brain development in children, in terms of time, intensity and duration of energy use, could influence the patterns of energy expenditure and weight gain in the future.
“We all know that the amount of energy our bodies burn has a decisive influence on weight gain,” Kuzawa said in a statement. “When children are 5 years old, their brains need almost half the energy they consume. However, we have no idea how much the energy expenditure of the brain varies in children. It is a huge gap in our understanding of energy expenditure. One of the main objectives of our study is to draw attention to this gap in understanding and encourage researchers to measure the use of brain energy in future studies linked to child development, especially those focused on understanding weight gain and the risk of obesity. ”
Another important unknown is how programs designed to stimulate brain development through different stimuli influence this energy expenditure.
“We believe plausibly that increased energy expenditure by the brain could be an unforeseen benefit for early childhood development programs, which, of course, have many demonstrated benefits,” concludes Kuzawa. “But it is essential to understand the mechanism since as that the energy needed for brain development decreases in older children and adolescents, the rate of weight gain increases. Our finding confirms a long-standing hypothesis in anthropology that states that humans, in childhood, develop at a pace much slower compared to other mammals and primates, something that is partly because our brains require more energy to develop.”