Want a Healthy Glow? Eat more Fruits & Veggies
Wednesday, November 28, 2012
A recent study offers one more reason to
layer on the sun block and eat your fruits and veggies. The study,
published in the British journal Evolution
and Human Behaviour indicates that a diet rich in carotenoids
increases skin yellowness, which may be perceived as being more healthful than
A healthy appearance has long been an
important influence in mate selection across species in the animal
kingdom. Birds and fish, for example, seek out mates with brightly colored
markings, as this sends a signal of general health and fertility. For humans,
making a connection between skin coloration and physical health has remained
In humans, melanin and carotenoids are
the main components that affect skin yellowness. Melanin contributes to
skin darkness/yellowness and is important for photo protection against damaging
UV rays. Carotenoids are important antioxidants that offer photo protection,
help boost the immune system and also contribute to skin’s yellowness.
In order to determine whether or not
humans have any preference for skin yellowness, researchers at the University
of Bristol in Bristol, UK created three studies examining different aspects of
skin lightness and yellowness and how they affect perceived health.
The first study considered
cross-cultural differences in preference for skin lightness and
yellowness. A popular belief, especially in Western cultures, is that
tanned skin appears healthier. However, in South Africa, skin lightening
products are frequently used because individuals with lighter skin are viewed
as more affluent, trustworthy and of a higher class.
To see if these fashionable trends
affect skin color preference across cultures, researchers allowed 32 UK-based
Caucasian participants and 31 black South African participants to alter skin
tones on 50 color-corrected facial images of the same ethnicity. Each
participant was instructed to “make the face as healthy as possible”.
Interestingly, both groups chose to increase the yellow coloring of the skin
and, to a lesser extent, also increased skin lightness. These results
established that there is no cross-cultural difference in preference for
increased skin yellowness and lightness despite fashionable trends.
Researchers then checked for a
correlation between yellow skin pigments and carotenoid intake – either from
dietary intake of fruits and vegetables or through supplementation with beta
Using one group of participants, the
researchers compared levels of yellowness on multiple body sites to their
self-reported levels of daily fruit and vegetable consumption. In a second
group, the researchers recorded baseline skin pigmentation and checked for
increased skin yellowness following 8 weeks of daily supplementation with 15 mg
In the end, the participants with the
highest fruit and vegetable intake and those that supplemented had the most
yellow skin pigments. The authors were able to determine that increasing
carotenoid consumption (either through diet or supplementation) leads to
increased skin yellowness.
The Bottom Line
While these preliminary findings warrant
further research into the links between appearance and health, they can
certainly have a positive impact on many people’s diet. Especially for
young men and women, whose dietary choices are often motivated by their desires
for improved physical appearance, this research could provide a much-needed
reminder to increase the amount of fruits and vegetables in their diet.