研究發現，考試前化妝的女性比不化妝的女性成績高出10%到20%。
Psychologists say the result could be down to the 'lipstick effect', whereby using make-up boosts self-esteem and has a knock-on effect on memory, confidence and mental ability.
The study in journal Cogent Psychology involved 200 female undergraduates, all studying the same subject with similar self-esteem, make-up habits and IQs.
The women were randomly split into three groups and asked to put on make-up, listen to music, or draw. All then took an exam based on a chapter of a textbook they had just read. Results showed the women who used cosmetics scored an average of 24.2 out of 30, compared to 19.9 and 22 in the other groups.
The researchers, from Harvard Medical School and Chieti University in Italy, said: 'Women may use make-up to increase self-esteem by boosting their attractiveness; this makes them feel better during stress. Positive emotions increase information accessible in memory.'
