Eating a breakfast packed with carbohydrates, such as white toast, pastries and cereal, can make people look less attractive in as little as two hours, scientists have found.
The puffiness and bloating that accompanies eating refined carbohydrates is known as “carb face” but until now scientists have never studied its impact on attraction.
For the new study, French researchers asked 104 volunteers to consume either a breakfast high in carbs, or a low-glycemic breakfast that can include foods such as porridge, eggs or fruit.
After two hours, participants had their picture taken and additional volunteers were asked to say which images they found most appealing.
Statistical analysis showed that consuming the high-carb breakfast was associated with lower facial attractiveness ratings for both men and women.
In contrast, eating a diet in fat, such as cheese or milk, made people appear better looking.
The team also asked volunteers to fill in questionnaires about their general eating habits, and found that chronic consumption of carbs throughout the day was associated with general lower attractiveness, while high-energy foods were linked to higher attractiveness ratings.
Men, however, were perceived as more good-looking if they snacked on carbs in the afternoon. The opposite was true for women.
Researcher Claire Berticat, of the University of Montpellier, said: “We have found that consumption of refined carbohydrates, whether immediate or chronic, affects facial attractiveness.
“We found that the results differed, at least for men, according to the different meals of the day – breakfast, afternoon snack and between-meal snack.
“The varying impact of different meals on attractiveness highlights the complexity of dietary influences on physiology.”
Researchers said there were scientific reasons why a high-carb diet may impact facial attractiveness, including triggering hypoglycemia which affects blood flow and the skin. It may also influence sex hormones which can change face shape.
Past research has shown female faces may change shape subtly during peak ovulation, becoming more attractive to men.