By ABBY ELLIN


It’s hard to ignore the hype over acai, the purple berry that dangles from 18-meter trees in the Brazilian rain forest and has found its way into detoxification beverages and anti-aging creams. Just browse through your email messages or advertisements on Facebook and you’ll get an idea of the claims and their celebrity supporters:“Lose weight with Oprah’s favorite diet secret!”

Fifty-three new food and drink products containing acai (pronounced ahcye- EE) were introduced in the United States in 2008, up from four in 2004. Sales of products with acai as the main ingredient exceeded $106 million in the year ending January 24, according to Spins, a market researcher specializing in natural products.

Naked (which is owned by Pepsi) and 180 Blue (Anheuser- Busch) offer acai beverages. Dr.Nicholas Perricone, a celebrity dermatologist, sells an acai supplement, and the cosmetics maker Fresh has a Sugar Acai Age-Delay Body Cream for $65.

The virtues of an acai-based beverage from a company called MonaVie have been extolled by the media mogul Sumner Redstone, who told Fortune magazine in 2007 that he hoped the juice, at about $40 a bottle, would help him live another 50 years. (He’s now 85.)

Despite the attention, there is little to back up the claims made on behalf of acai. While the berry does contain antioxidants - molecules that can slow damage caused by the oxidation of other substances in the body - there are no long-term studies proving that acai removes wrinkles or, as the detoxification products claim, cleanses the body of toxins. Nor is there evidence to support dieters’ hopes for a magic fruit.

“There is currently no scientific research to support a weight loss claim for acai fruit,”said Stephen T.Talcott, associate professor of food chemistry at Texas A&M University, who has published several studies on the berry.

While most of the companies are careful about how they market their products, others are employing questionable means. Oprah Winfrey, the media mogul, who has information on her Web site about acai attributed to Dr.Perricone and another physician who appears frequently on televison, is so concerned that her name has been misused to promote products across the Internet that a disclaimer was added to her Web site last month:“Consumers should be aware that Oprah Winfrey is not associated with nor does she endorse any acai berry product or online solicitation of such products.”

To date, there have only been a few small studies of the berry on humans. One involved 12 volunteers who consumed a single serving of acai juice or pulp. The study, which was published in the September 2008 Journal of Agricultural and Food Chemistry showed a short-term increase in the antioxidant capacity of the volunteers’blood.“It’s got good antioxidants,”said Dr.Talcott, one of the researchers on the study.“We know antioxidants are probably good for us. But we need more studies.”

But some people swear it works. About a year ago, Sarah Taylor, 32, a massage therapist in Portland, Oregon, began using Sambazon’s acai powder. After the first day, she said she noticed a spike in her energy level and has been using it ever since. She even suggested her older clients drink it.“It is so exciting to watch people react to something so well,”she said.