Our cravings for sweetness: nature or nurture?
02 April 2014
Our in-built taste for sweet foods helped keep us healthy in early
human evolution because it indicated the presence of vitamins and
minerals in foods, Professor Hely Tuorila, of the Department of Food
Sciences at Helsinki University, told the International Sweeteners
Association conference in Brussels yesterday (02-04-14).
“The problem today is that the amount of sweet food we eat has grown
out of proportion with the rest of our diet,” said Prof Tuorila. Added
to which some people experience cravings for chocolate and other sweet
foods that result in them eating “outside normal limits.”
“Likings for sweetness in food and drink also varies between food
cultures,” explained Prof Tuorila. “Comparisons between Australia and
Japan, for example, show Australian consumers prefer their breakfast
cereal sweeter than Japanese consumers who in turn prefer much sweeter
orange juice than Australian consumers.”
But how much is our preference for sweetness due to food culture or inherited genetic traits?
“About 50% of our liking for sweet food and drinks is attributable to
genetic traits, about the same level of heritability as personality
traits or asthma,” said Prof Tuorila.
“The frequency of eating sweet foods seems also to be an interrelated
heritable trait and related to emotional, or comfort, eating.
Both findings come from trials by Prof Tuorila and colleagues who
studied nearly 900 sets of identical British female twins. “Women of all
ages, from 17 to 82 years old, have a strong liking for chocolate, ice
cream, sweets, both sugar and low calorie sweetened soft drinks, and
fruit – although they never crave fruit.”
While Prof Tuorila found women’s liking for most sweet foods fades
slightly with age, their liking for chocolate (and fruit) remains
Lifelong liking for sweet foods is similar among Finnish identical
male twins, but men in general like sugar sweetened soft drinks and ice
cream more than women. “Men also have a stronger liking than the women
for pizzas and burgers,” commented Prof Tuorila.
“Living without sweet food and drink is difficult because of its
biological, psychological and social role in our lives,” said Prof
Food culture might influence our preferred intensity of sweetness in
food and drink, but for some people a genetic ‘sweet tooth’ makes it
much harder to live without sweetness. “For those people in particular
low calorie sweeteners are especially useful,” concluded Prof Tuorila.
Janette Marshall, Nutrition and Health Journalist