Two years ago Hendy Lund, then a 30-year-old computer networking professional in Silicon Valley, enjoyed making love with her husband almost every night. In just a few months, and for no apparent reason, her libido vanished. "We went from doing it almost daily to doing it maybe once a month -- and even that was more than I really wanted."
Lund pondered possible reasons for the abrupt change in sexual desire. "I was working long hours for a start-up. But I'd had intense jobs for years. My problem didn't seem connected to anything at work. Steve and I had been together awhile, and over time, sexual intensity usually diminishes. But this was more than cooling. All of a sudden, I was in the freezer. Honestly, I had no idea why I lost my libido. But it was like I was a car whose engine would grind and grind but never quite turn over."
Lund's husband, Steve, then 35 and in the process of switching careers from health care to law enforcement, wasn't pleased with having sex just once a month. He and Hendy remained close and committed to one another, but agreed that the libido loss strained their marriage.
Then Lund saw an advertisement in a local weekly looking for women with sex problems for a study of a new treatment, a nutritional supplement. "I was skeptical," she recalls. "Vitamins for a better sex life? It seemed far-fetched. But I wanted my libido back, and Steve did too, so I called."
The ad had been placed by the Daily Wellness company of Mountain View, Calif., founded by Dr. Hank Wuh. Lund visited the company's Web site and saw no products claiming sexual enhancement for women. But she found ArginMax for Men, and perused its ingredients: two herbs (ginseng and ginkgo), the vitamins and minerals found in many one-a-day products and something called L-arginine. "I figured they were developing a similar product for women. I've taken vitamins for years, and I was familiar with the herbs. But I didn't know anything about L-arginine."
Lund did a Web search and quickly discovered that L-arginine is an amino acid present in foods containing protein. "It seemed safe enough," Lund recalls. She signed up for the study.
Lund filled out a standard questionnaire used to assess sex problems. It asked about sexual desire, vaginal dryness, frequency of intercourse, pain on intercourse, frequency of orgasm, sexual satisfaction and overall relationship satisfaction. Then she received an unmarked bottle of tablets and was told to take six a day for 30 days.
"For two weeks, I felt nothing," Lund recalls. "Then I began to feel more sexual energy. The engine began to turn over. By the end of the 30 days, we were back to doing it three times a week -- and I wanted to."
When the researchers broke the code, it turned out that Lund had taken Daily Wellness' new creation, ArginMax for Women, a product similar to the one for men, but with a slightly different formula: more calcium and iron (which women need more than men), less zinc (which men need more than women), a little less ginseng and L-arginine and one additional herb, damiana.
The study involved 77 participants -- 34 of whom received ArginMax for Women while the other 43 took a placebo. The results, published in the October 2001 issue of Journal of Sex and Marital Therapy, showed that the ArginMax group reported significant improvements in libido, frequency of intercourse, sexual satisfaction and overall relationship satisfaction. They reported less vaginal dryness and less discomfort during intercourse. The ArginMax group also reported a trend toward increased frequency of orgasm, but this did not quite reach statistical significance. (The ArginMax caused no significant side effects.)
The study was coordinated by Mary Lake Polan, chairwoman of the department of obstetrics and gynecology at Stanford. She is quick to point out that she's no promoter of herbs and vitamins. "I'd say 99 percent of my practice is mainstream medical," she says. Polan was skeptical when 40-year-old Dr. Wuh approached her about studying his new supplement. She knew that vitamins play important roles in every body process, including sexuality, but that didn't necessarily mean that vitamins enhance sex.
But the doctor was intrigued by the herbs in Wuh's product: ginseng, ginkgo and damiana. "Fifteen years ago, I did a fellowship in Hunan, China, and I saw firsthand the medical effectiveness of Chinese herbs. Many of my patients take herbs and vitamins, and do yoga and use other complementary therapies, so although I'm not a big believer in them, I'm open-minded."
Still, Polan was reluctant to get involved. What convinced her were Wuh's scientific credentials -- an M.D. from Johns Hopkins, an M.P.H. from Harvard and a fellowship at Stanford -- plus the scientific case he made for the ingredients in his ArginMax products.
First there was ginseng, which Asians have considered a sex enhancer for centuries. A 1995 Korean study published in the International Journal of Impotence Research lends credence to that belief. The researchers gave 90 men with erection impairment one of three treatments: a placebo, an antidepressant or ginseng. The placebo and antidepressant groups both showed 30 percent improvement in erection rigidity and girth. But those in the ginseng group improved 60 percent. (The same physiological mechanisms that deliver blood to the penis in men direct it into the clitoris, vulva and vaginal wall in women.)
Ginseng also has been shown to enhance overall feelings of well-being -- an important, if elusive, component of libido. In a 1996 study in the journal Drugs in Experimental and Clinical Research, Mexican researchers surveyed 501 people about their health and well-being. Then 162 members of the group were given a daily multivitamin supplement, while 338 were given the same formula plus ginseng. After four months, all the participants were surveyed again. Both groups reported improved feelings of well-being, but those taking the ginseng reported significantly greater improvement.
Then there was gingko. Many studies show that ginkgo helps improve blood flow. Most of the research has focused on the brain, where herb-induced improvement in circulation has been shown to help slow the progression of Alzheimer's disease and lead to modest but measurable memory improvement in healthy individuals. In addition, ginkgo improves blood flow into the genitals, which can help treat sex problems. A 1989 study published in the Journal of Urology shows that ginkgo helps relieve impotence caused by narrowing of the arteries that supply blood to the penis. Sixty men with erection problems caused by impaired penile blood flow took ginkgo daily. A year later, half the men had regained the ability to raise erections.
Ginkgo also helps treat the loss of libido and sex problems common among those who take pharmaceutical antidepressants. In a 1998 study published in the Journal of Sex and Marital Therapy, University of California, San Francisco, researchers gave ginkgo to 63 people suffering from sex problems due to antidepressants. The herb relieved the sex problems of 91 percent of the women and 76 percent of the men. The women reported improved vaginal lubrication. The men were better able to raise erections. And both the men and women reported more sexual desire and more pleasurable sex. (There was no placebo group in this study, so it can't be regarded as scientifically rigorous. However, placebos usually benefit around one-third of those who take them. The response rate in this study was much greater than that.)
And the last herb was damiana, which has been regarded as a folk aphrodisiac in Latin America for centuries. Research has been scant, but a 1999 study in the journal Psychopharmacology shows that when laboratory animals are given damiana their copulatory frequency increases.
The non-herb component was the amino acid L-Arginine -- the precursor of nitric oxide (NO) -- which plays a key role in synthesis of a compound in the body (cyclic guarosine monophosphate, or cGMP). This compound plays a crucial role in blood circulation into the genitals and sexual responsiveness. Studies have shown treatment with L-arginine increases levels of NO and cGMP, and is essential to the sexual maturation of laboratory animals.
"The presence of L-arginine in the product made a huge difference for me," Polan recalls. "There were clear metabolic reasons why inclusion of L-arginine could increase levels of NO and cGMP, and have sexual benefits."
Wuh also showed Polan the results of a pilot study of ArginMax for Men, published in 1998 in the Hawaii Medical Journal, a publication not widely read on the mainland. In this study, 21 men complaining of erection impairment took ArginMax for Men for a month. Almost 90 percent reported better erections. The product caused no significant side effects.
Both the Hawaii study and Polan's were financed by Daily Wellness, maker of the ArginMax products. This is not at all unusual. Studies of new drugs are almost entirely financed by the companies that make them -- and the Food and Drug Administration uses those studies as the basis for new drug approvals.
"Of course we paid for the studies," says Wuh, who is also the author of the book "Sexual Fitness." "Who else would?"
Some drug companies insist that as a condition of funding, the researchers relinquish control of the results -- leading to recent charges that some companies suppress studies showing their products ineffective or hazardous. Polan signed no such documents. "I felt no pressure from Daily Wellness," Dr. Polan explains. "I was free to publish no matter how the study turned out."
"I had nothing to do with the ArginMax studies, and I don't lend my name to products," says neurophysiologist Beverly Whipple, a professor emerita at Rutgers, a former president of the American Association of Sex Educators, Counselors, and Therapists, and current president-elect of the Society for the Scientific Study of Sexuality.
"But I've been involved in research on women's sexuality for over 30 years," says Whipple. "I was impressed by Hank Wuh's book, and by the ArginMax studies. The drug companies treat women as though they're mini-men. They can't understand why Viagra doesn't work for women. Well, it doesn't. But in a double-blind, placebo-controlled trial, ArginMax did. As a neurophysiologist, I find that very interesting. If women have problems with their sexual satisfaction, I think ArginMax is worth a try."
Jason Brodsky, a spokesperson for the Food and Drug Administration, explains that drug companies typically finance the research that demonstrates the safety and effectiveness of their products. There is no independent funding source except the government, and that would mean an enormous tax-funded subsidy to the drug industry. Of course, bias can creep in when a party with vested interest in the outcome finances research of its own products. As an oversight, pharmacology reviewers at the FDA analyze drug studies and scientists who have nothing to do with the study or company review supplement studies before they are accepted for journal publication.
While ArginMax produced statistically significant improvement in sexual function, it did not work for everyone who tried it. Cynthia Katz, a San Francisco nurse says: "My libido isn't what my husband would like it to be. I read about the study and took it for a month. For the first two weeks I felt nothing. Then I began feeling something in my genitals -- but it wasn't more libido. It was more like irritation, like I was coming down with a yeast infection. By the end of the bottle, I had no change in libido, so I stopped taking it. Soon after, the irritated feeling went away."
Polan is quick to point out that ArginMax is not an aphrodisiac in the popular sense of the term -- something that quickly throws libido into overdrive. It takes several weeks to experience benefit, and not everyone does.
"Both ArginMax studies had small numbers of subjects, so I'm not ready to get up on a soapbox and declare these products sure cures for male or female sexual dysfunction. On the other hand, among my women patients, sexual complaints are quite common, and have become even more common since the publicity around Viagra brought these problems more out in the open. ArginMax costs only about $1 a day. Mainstream medicine has no good treatments for female sexual dysfunction. And many men can't take Viagra because of medical problems. My attitude is: If you have sex problems, it just might help."