JMIR Publications

ABSTRACT

Background:

Inadequate fruit and vegetable consumption causes a considerable disease burden and premature mortality. Despite considerable public health promotion of a healthy diet the average consumption is still below recommended levels. Fruit and vegetable consumption influences human skin colour, increasing red/yellow/orange pigment in the skin. Given that this colour is deemed attractive and healthy-looking, the appearance benefit may provide motivation to eat more fruit and vegetables. Such appearance motivation could be particularly effective in young individuals who currently eat least fruit and vegetables.

Objective:

To assess how widely the impact of diet on skin colour is known within the UK. To compare the strength of motivation to eat fruit and vegetables based on health and appearance benefits and to compare the effect of different UK demographics on motivation.

Methods:

Four groups of UK residents (N = 200 each group) were recruited through the Prolific online platform. Groups comprised younger (aged 18-24) and older adults (aged 40-60) of low and high self-reported socioeconomic status (1-5 and 6-10 on a 10-point rating scale). Facial images simulating the skin colour associated with low and high fruit and vegetable diets were shown to participants. Questionnaires were used to assess (1) background knowledge of the health and skin colour effects of dietary fruit and vegetables; (2) the specific motivational impact of the skin colour illustration and (3) the relative importance of motivation to consume fruit and vegetables arising from health and skin colour appearance benefits.

Results:

(1) 61% of all participants were unaware of the dietary–skin colour association. (2) 57% of participants found the simple demonstration of the dietary impact on skin colour positively motivating to eat more fruit and vegetables. The visual demonstration was equally motivating for participants of high and low self-reported socioeconomic status (P = .63) and different ethnic backgrounds (White N = 453, Black N = 182, Asian N = 87, P = .22). Health benefits from a diet high in fruit and vegetables were regarded as more motivating than skin colour appearance benefits. The appearance benefits of a high fruit and vegetable diet (compared to the health benefits) were relatively more important for the younger participants (Mann-Whitney U = 96,263, P < .001) and for women (N = 489) than for men (N = 310, U = 83,763, P = .01).

Conclusions:

These findings indicate that promotion of the skin colour effects of diets high in fruit and vegetables could provide additional motivation for a healthier diet. Our study indicates the wide appeal of appearance benefits from dietary fruit and vegetable (across ethnicity and socioeconomic status) and particularly amongst young adults where inadequate diet is most prevalent.