Obese children have a less-sensitive sense of taste compared with kids of normal weight, a new study suggests.
Their blunted ability to distinguish the five tastes of bitter, sweet, salty, sour, and umami (an earthy, savory flavor) may prompt obese children to eat larger quantities of food to register the same taste sensation, the researchers said.
The results are based on a study of 94 normal weight and 99 obese children ages 6 to 18, who were in good health and not taking any medications known to affect taste and smell.
Participants tasted 22 "taste strips," which were placed on the tongue —for each of the five taste sensations, there were four strips of varying intensity — for example, a very salty strip, a salty strip, a somewhat salty strip, and a slightly salty strip — plus two blank strips. The children were asked to identify the taste of each strip, and rank them by their intensities.
Children could score a maximum of 20 points, by correctly identifying all five types of tastes at the four different intensities. Scores ranged from two to 19.
Girls and older children were better at picking out the right tastes, according to the researchers.
Overall, the children were best able to differentiate between sweet and salty, but found it hardest to distinguish between salty and sour, and between salty and umami.
Obese children found it significantly more difficult to identify the different taste sensations, scoring an average of 12.6, compared with an average of just over 14 by children of normal weight.
Exactly why people have differing taste perceptions is unclear, but genes, hormones, cultural experiences and exposure to different tastes early in life are all thought to play a part, say the authors.
Previous research indicates that heightened sensitivity to different taste sensations may help to reduce the amount of food eaten as less is required to get the same "taste hit," the researchers said.