Does good skin come in a tablet?

Great skin just got another wrinkle.

Cosmetic treatments are no longer just about creams and emollients — the latest trend is about working from the inside out. "Ingestibles" are supplements such as omega-3 oils, alpha lipoic acid, grape seed, pomegranate extract and many other nutritional-sounding words you never used to hear at the cosmetics counter.

While supplements have long been a staple at health-food stores, many credit Nicholas Perricone, the New York dermatologist-to-the-stars, as fueling the beauty-biz trend with his best-selling books, such as "The Perricone Prescription." He recommends eating a lot of salmon, among other foods high in omega-3 oils. Perricone's line of supplements is sold at stores such as Sephora; a multipack is $130.

Here's a closer look at beauty ingestibles, which hope to capture a significant share of the $45-billion-a-year cosmetic and skin-care market.

The science

Since skin is our body's largest organ, it reflects our health. So, as Harvard-trained dermatologist and cosmetic surgeon Carolyn Jacob says, "The creams and lotions and potions you put on top of your face mean nothing if you're not eating well."

Foods with antioxidants as well as foods with anti-inflammatory properties are the key to preserving a youthful appearance, says Jacob. Refined sugar and flour and trans-fats are all examples of inflammatory foods.

"Inflammation and oxidation can both assist in the breakdown of tissue and cell destruction, leading to wrinkles and other skin problems."

The foods

A sampling of books by doctors, dermatologists and dietitians (including such respected names as Dr. Andrew Weil, Dr. Michael Roizen and Dr. Mehmet Oz, with their latest best-seller "You: Staying Young") lists some of the top antioxidant foods as acai berries, celery hearts, onions, spinach, kale, cocoa beans, blueberries, cranberries, kidney beans, red beans and hazelnuts.

Some of the foods high in anti-inflammatory properties are lemons, salmon, seaweed, green tea, flax seed oil, cinnamon, ginger, raw almonds, walnuts and the spice turmeric.

So why add supplements?

Doctors and nutritionists say even people who make a point of eating a diet rich in healthy, unprocessed foods don't get all the nutrients they need. Whether it's food processing, a time lag from harvesting to getting produce to the table or the environment we live in, doctors say it's easy to miss out on vitamins. Vitamins and supplements, write Oz and Roizen, "are an insurance policy for an imperfect diet."

Some ingredients that have been proven to help with skin include alpha lipoic acid; pine bark extract; grape seed extract; omega-3 fatty acids; vitamins A, C, E and D; calcium; magnesium; copper; selenium; and biotin, Dr. Jacob says. You can find all of them in the vitamin and supplement aisle of grocery, drug- and health-food stores.

Do ingestibles work?

Medical experts seem to agree that supplements aren't harmful in recommended doses. But do they actually work?

"We know that things we ingest can have a positive or negative effect on our bodies and skin, and antioxidants or anti-inflammatory foods have a positive effect," says Dr. Michael Reep, a dermatologist in Westlake, Ohio. "But supplements per se haven't thoroughly been studied, so we don't know if they'd have the same effect. The FDA hasn't examined this, we don't know exactly what's in the supplements and so on.

"Theoretically, they might help, but for now you have to keep it as theoretical."

That said, Reep himself buys supplements that he thinks are good for his skin, but he gets them at GNC: CoenzymeQ10, green tea and grape seed extract, and vitamins C and E.

"If people want to spend the extra money on supplements, they can do that," he says.

What's out there?

Dozens of new ingestible lines are on the market, ranging widely in price. On the lower end, Target offers a range from the British-based Boots Chemists, designed to cleanse, purify and revive the body; it's $19.99 for a five-day supply.

From there, prices rise dramatically. The Perricone line, available at some department stores and Sephora, includes omega-3 wild sockeye salmon oil soft gels, Super Berry Powder and a Skin & Total Body packet ($130 for a 30-day supply). The Dr. Murad line, also available at Sephora stores, offers a supplement formula that costs $125 for a one-month supply.