Here's a question to ponder: Why is acne common in the Western, industrialized world, while the pimples that trouble American kids are rare in developing countries?
It's a puzzler -- and one that prompted Australian researchers to ask whether changing the diet of teenagers would have any effect on acne.
The results could change the way dermatologists think about diet.
To test their theory, the Australian researchers recruited 50 young men between ages 15 and 25 with mild-to-moderate acne. They split the volunteers into two groups: One group was instructed to eat a diet of lean meat, poultry and fish, along with fruits and vegetables. They replaced foods such as white bread and highly processed breakfast cereals with whole grains. Meanwhile, the other group ate a typical Western diet.
After 12 weeks, researchers found that the group eating more protein and whole grains experienced drastic results, according to the researchers.
"The acne of the boys on the higher-protein, low-glycemic index diet improved dramatically, by more than 50 percent, which is more than what you see with topical acne solutions," wrote senior author Neil Mann, an associate professor at the Royal Melbourne Institute of Technology in Australia.
The typical teenager's diet -- rich with foods like doughnuts and cheeseburgers -- appears to raise hormone levels, and surging hormones have long been linked to acne.
"A diet high in processed foods pushes glucose and insulin levels higher, exacerbating the problem, but low-glycemic foods do the opposite," Mann said. "The mechanism and the results are clear as day."
Although the study was small, Altamonte Springs, Fla., dermatologist Jerri Johnson thinks the study's authors may be on to something -- even though the Web site for the American Academy of Dermatology explicitly says there's no link between diet and acne.
"It's worth telling patients about because it shows that diet is important," says Johnson. "We do know that acne is a more severe disease in Westerners ... so there's got to be some connection there."
Indeed, says Dr. Barbara Reed, a Denver dermatologist and spokeswoman for the AAD, "I happen to agree that our diet is so full of fats and refined sugar that it can't be so good for us, probably in more ways than just causing acne. Every diet for health -- colon cancer prevention, breast cancer prevention, heart disease prevention -- is the same: more fresh fruits and vegetables, less fat, red meat, sugar."
But Johnson also thinks it's too soon to conclusively link acne to diet. Dermatologists have long believed that acne depends on many factors, including heredity and hormonal changes.
"Years ago, we used to think that chocolate and Cokes cause acne," says Johnson, but the dermatology community moved away from that.
Today, patients with mild-to-moderate acne are typically given a retinoid such as Retin-A and topical antibiotics. But Johnson usually advises her patients to drink lots of water and avoid greasy, high-fat foods.
"I think diet does play a role," Johnson says, but she believes some people inherit genes that predispose them to acne.
The Australian researchers began looking at the link between Western diets and acne because there's more and more evidence that eating a Western-style of diet is linked to acne, noted researcher Robyn Smith.
For instance, recent surveys of skin diseases in developing countries have found that acne is more prevalent in schoolchildren from higher socioeconomic areas, she notes. That seems to echo what researchers observed in Inuits, or Eskimos, when they began adopting a more Western lifestyle.
"Along with acne, the Inuits also developed higher rates of obesity, diabetes, dental [cavities] and heart disease," says Smith. "It's interesting that the other maladies are commonly associated with diet, yet acne isn't."
Still, the more critical question may be this: Will an American teenager give up junk food in hopes of getting rid of acne?
It's possible, says Johnson.
"It all depends on the kid. The same kid who will use his topical medication every day would probably be willing to stick to the diet," she says. "The ones who won't bother are the ones who won't put on their topical medication either."
Linda Shrieves writes for The Orlando Sentinel.