THURSDAY, March 8, 2012 (HealthDay News) -- The key to a rosy, healthy-looking complexion may be as simple as eating more fruits and vegetables, researchers say.
"We found that within a six-week period, fluctuation in fruit and vegetable consumption was associated with skin-color changes," said lead researcher Ross Whitehead, from the School of Psychology at the University of St. Andrews in Scotland.
Not only did skin look healthier at the end of the study period, it was judged more attractive as well, he said. "Eat more fruits and veggies to improve your appearance," he added.
Practically, this may be a useful motivational tool for dieters, Whitehead said. "We are currently running randomized controlled trials to investigate whether seeing the potential appearance gains on images of one's own face are sufficient to motivate dietary change. Pilot trials have been encouraging so far," he added.
For the study, published March 7 in the online journal PLoS ONE, Whitehead's group looked at the fruits and vegetables 35 people ate over a six-week period.
They found that redness and yellowness in skin increased as more fruits and vegetables were consumed.
This is due to the impact of carotenoids, Whitehead said. "These are red/yellow plant pigments, which are distributed to the skin surface when we eat fruits and veggies," he said.
The changes in skin color that were associated with eating more fruits and vegetables were linked in a second experiment with increased attractiveness. This suggests that skin color reflects better health, the researchers said.
"Our study suggests that an increase in fruit and veggie consumption of around three portions over a six-week period is sufficient to convey perceptible improvements in the apparent healthiness and attractiveness of facial skin," Whitehead said.
"Conversely, those that worsened their diet became paler," he said.
The carotenoids studied included beta-carotene and lycopene. Foods rich in beta-carotene include carrots, yams, spinach, peaches, pumpkin and apricots. Lycopene is present in apricots, watermelons, tomatoes and pink grapefruits.
Nearly all of the study participants were white, so more work is needed to see how diet affects other groups, the researchers noted.
Also, the study was small, and the results merely show an association not cause and effect.
Still, other experts supported the findings. "This is something I have been saying for a very long time," said Dr. Doris Day, a dermatologist at Lenox Hill Hospital in New York City.
"We are really what we eat, and it shows in your skin -- and there are no shortcuts," she added.
There are studies that show a high-antioxidant diet -- one with olive oil, nuts, more fruits and vegetables and less dairy and red meat -- helps skin resist aging changes and skin cancer, Day said.
"You want to look for different colors of fruits and vegetables, because each color has its own special benefit," Day added.
Also, opt for the fruit itself, including skin and pulp, rather than juice. "If you eat the whole plant, then you have the best chance of getting the whole benefit from the plant," she added.
"Your skin is a reflection of your overall general health," Day said. "The healthier your skin is, the better it functions, the more it can help the rest of your body function; the healthier the rest of your body is, the healthier your skin is as well."
Samantha Heller, a dietitian and nutritionist at the Center for Cancer Care at Griffin Hospital in Derby, Conn., agreed. "Fruits and vegetables are loaded with healthy plant compounds that keep skin healthy, structurally strong and protect it from the damaging rays of the sun," she said.
It has long been known that many plant substances, such as the carotenoids beta-carotene and lycopene, contribute to the skin color, she said.
"These compounds are also potent disease fighters," she added.
Only 25 percent to 30 percent of Americans eat the recommended amounts of fruits and vegetables, and efforts to increase consumption have not been too successful, Heller noted.
"But once the word gets out that eating fruits and vegetables can make you sexy, attractive and maybe even look younger, hopefully, the carrots, kale and cantaloupe will be flying off the shelves and into people's meals," she said.
For more information on a healthy diet, visit the U.S. Department of Agriculture.