Considerable attention is being paid to the energy load of foods, and in particular the saturated fat content, as the world grapples with an obesity epidemic that risks putting enormous strain on health care budgets.
Major food companies need to show they are on-board with healthier eating messages – but the foods they produce must also be acceptable to consumer palates, and cater to the demand for indulgent ‘treat’ foods.
The researchers involved in the new study, published in the journal Neuroimage, note that the fat component in food has a strong influence on texture and palatability – as well as on the body’s energetic balance and its supply of essential fatty acids.
“High fat foods are often consumed with more pleasure, and in larger quantities than healthier foods like vegetables. Such hedonic drives can produce inappropriate eating behaviors, obesity, diabetes, and hypertension,” wrote the researchers, led by Micah Murray.
They propose that food evaluation based on visual information before it is eaten might be the perceptual stage at which the individual makes nutritional choices.
The study involved 19 adults aged between 25 and 49 years, who were shown images of food and non-foods and asked to discriminate between them. Unbeknownst to the participants, the images of food were also divided into low-fat and high-fat.
Their brain activity was measured electo-encephalography technology.
Murray’s team found that the human brain assesses the reward properties of a food very quickly, and in parallel with the brain regions responsible for categorization and decision-making.
This is said to be the first time such processes have been investigated in humans, giving an indication of the brain regions where food choices are made.
“We discovered that the adult brain can estimate the fat content of food simply from visual information, and that this process happens within 200 milliseconds,” said Nestle research scientist Julie Hundry.
Specifically, the brain made very rapid distinctions between the high- and low-fat foods; moreover, the regions of the brain that are typically associated with assessing the likely reward from an action and making decisions were seen to respond more strongly to high-fat foods than to low-fat.
“These results will help Nestle understand how the brain processes and interprets the nutritional value of food.”
The research was a collaborative project between the Nestle Research Center, the Centre Hospitalier Universitaire Vaudois and the University of Lausanne Centre d’Imagerie Biomedicale.
Neuroimagedoi:10.1016/j.neuroimage.2008.10.005 “The brain tracks the energetic value in food images”
Authors: Ulrike Toepel, Jean-François Knebel, Julie Hudry, Johannes le Coutre and Micah M. Murray