Can early exposure shape better diets for future generations?
The idea that childhood consumption of foods can shape later taste preferences is not new, yet we also know they do significantly change over the course of a lifetime. But could industry use this information to drive the dietary changes that are needed to reverse the current ‘obesity epidemic’?
Every aspect of early exposure to food and nutrients seems to help shape later preferences – whether it is the type of food we are fed or the way in which we are fed it, these early exposures to foods seem to have drastic effects on our later taste preferences and risk of obesity.
For example, a recent BMJ study from researchers at the University of Nottingham, UK, reveals that weaning methods have a significant impact on food preferences and health in early childhood.
“Infants weaned through the baby-led approach learn to regulate their food intake in a manner which leads to a lower BMI and a preference for healthy foods like carbohydrates,” said the UK-based researchers. “This has implications for combating the well-documented rise of obesity in contemporary societies.”
Perhaps more interesting though is the question of whether the ingredients that go into baby foods and infant formula can have any long term impact on food preferences.
We know already that early exposure to foods containing added salt can shape a greater preference for salty tastes throughout infancy and childhood. For example, research published in the American Journal of Clinical Nutrition last year found children and infants introduced to starchy table foods containing added salt before the age of six months have a greater preference for salty tastes.
“Liking salt and salty foods is a learned taste preference and the recommendation that the adult population reduce their sodium intake will be more successful if children do not develop a preference for salt in the first place,” said Clare Farrand, international programme lead for World Action on Salt and Health (WASH). “This can only be achieved if children are given a diet which is low in salt.”
Meanwhile, data from researchers in the US has shown that infants and young children base many food choices on familiarity and sweet taste.
“The low cost and ready availability of energy-containing sweeteners in the food supply has led to concerns that the rising consumption of added sugars is the driving force behind the obesity epidemic.”
Indeed, researchers at Queen's University of Belfast, have even found that prenatal exposure to food stimulus has an effect on food flavour preferences up to nine years later.
“Children exposed to garlic in the womb ate a greater percentage of garlic flavoured potato than children not previously exposed to this stimulus,” explained the researchers – led by Professor Peter Hepper.
“This study demonstrates in humans, for the first time, that prenatal chemosensory experiences may persist and influence behaviour well into childhood, some years after the initial experience,” said Hepper and his team.
A self-perpetuating cycle?
The idea that early exposure affects long term preferences is backed up by work performed by Dr Bettina Cornwell from the University of Oregon, USA, who found children’s knowledge and consumption of fast food has significant impact on their palate and preference for foods that are high in sugars, salts and fats.
In the research Cornwell questions why food and beverage manufacturers have come to offer so many products high in sugar, fat, and salt.
“One possible answer is that it has occurred in the pursuit of taste preference,” she suggests – noting that competitive market forces "continually push companies to offer products that are preferred over others.”
In this scenario children’s demand for products containing high levels of salt is then met by manufacturer supply of foods that contribute to unhealthy eating habits.
Cornwell said this appears to have become “a self-perpetuating cycle.”
If Cornwell is to be believed, the big question is whether we can break the cycle and create foods that might create a long term preference for healthier foods.
“Parents are doing the best they can, but the food industry needs to take greater responsibility,” argued Farrand. “Until this is the case children remain at risk of developing serious health issues in later life."
