A 17-year study of more than 9,000 children suggests that children who eat more ultra-processed food are more likely to be overweight or obese as adults.
The researchers also found that ultra-processed foods -- including frozen pizzas, fizzy drinks, mass-produced bread and some ready-to-eat meals -- accounted for a very high proportion of children's diets -- more than 60% of calories on average. One of the key things uncovered here is a dose-response relationship.
This means that it's not only the children who eat the most ultra-processed foods that have the worst weight gain, but also the more they eat, the worse this gets.
Industrial food processing modifies foods to change their consistency, taste, color and shelf life, using mechanical or chemical alternation to make them more palatable, cheap, appealing and convenient -- processes which don't happen in home-cooked meals. Ultra-processed foods tend to be more energy-dense and nutritionally poorer. They often have high levels of sugar, salt and saturated fats but low levels of protein, dietary fiber and micronutrients, and they are aggressively marketed by the food industry.
The link between child health and ultra-processed food was complex, and socio-economic factors likely played a large role.
The results of this study are not surprising: children who consume a lot of 'ultra-processed' foods are most likely to be less healthy and more obese than their peers with lower intake. The interpretation of these results are however much more difficult.
The outcome of the study is heavily confounded by socio-economic factors: children living in more deprived areas and from families with lower educational attainment and lower socio-economic status had the highest intake of ultra-processed foods. Unfortunately, these children are also at highest risk of obesity and poor health, as there are still considerable health-inequalities in the UK and socio-economic status is an important determinant of health.
The researchers found, on average, that children in the groups that ate more ultra-processed foods saw a more rapid increase in their BMI, weight, waist circumference and body fat as they grew up.
While the study shows a link between eating ultra processed foods and increases in BMI and body fat, it doesn't definitively show cause and effect.
According to the researchers, more radical and effective measures are needed to reduce children's exposure and consumption of ultra-processed foods.
