Sex Sells

References

People are intrigued by sex, and there is no shortage of conversation about the topic. Likewise, there is no shortage of products that promise to improve the average consumer’s sex life. Take, for example, the hoopla over Pfizer’s Viagra®. The little blue pill is known for improving sexual performance and erectile function, and has given new life to many older couples’ sex lives, as well as spawned countless imitation products.

“With the aging of the ‘boomer’ population, interest in sexual health is stronger than ever,” said Edward Lee, president of AIDP Inc., which supplies LongJaX®, an Eurycoma longifolia Jack extract said to improve libido. “Sexual health can be considered a barometer of overall health, so wellness and anti-aging products will often improve sexual health. Plus, sexual performance is often tied to feelings of significance and selfesteem, so there are strong motivators for addressing sexual issues.”

On the natural front, supplements address sexual issues such as waning sex drive and fertility. Contrary to Viagra’s purpose, however, nutraceuticals and herbs are intended more for maintenance and improvement in overall sexual wellness rather than instant gratification.

These products can both boost libido and enhance fertility, while often simultaneously improving general wellness.

In stocking a sexual health section, retailers should pay careful attention to the research behind various products, as well as the companies they buy from. “Retailers should look for not only how thoroughly corroborated a product is by research, but also the standing and reputation of the company whose product they are selling,” said Aftab Ahmed, Ph.D., vice president of R&D at Phoenix based Naturally Vitamins. “If they do that, they will be serving the health care needs of their customers.”

Amping Up a Waning Libido

A decreased sex drive is just one aspect of sexual dysfunction, and as a cross-gender problem, it is being addressed by male- and femalespecific products. “[Nutraceuticals] provide a natural solution and are a little more discreet than having to go to your doctor for a prescription,” said Jesse Lopez, president and chief executive officer (CEO) at Chicago-based Source One Global. “Too often, there are negative side effects associated with pharmaceutical products that are not associated with natural products.”

Aphrodisiac supplements, purported to enhance libido and sexual pleasure, often contain numerous ingredients—from botanicals to micronutrients and beyond—most of which are supported by research and anecdotal reports. One combination product, known as ArginMax™ (made by The Daily Wellness Co. in Sunnyvale, Calif.), contains ginseng, Ginkgo biloba, damiana, L-arginine, vitamins and minerals. In a clinical trial, women taking the supplement reported improvements in satisfaction with overall sex life and sexual desire compared to women who received placebo.¹

Individually, these ingredients have been studied for their effects on sexual function as well. L-arginine, the active form of the non-essential amino acid arginine, is commonly studied in sexual health because it is a precursor to nitric oxide (NO). NO production is essential for relaxing blood vessels and the corpus cavernosum (the area of the penis that fills with blood in response to stimulation), which makes it necessary for male sexual function.²

One trial of 29 men showed oral L-arginine supplements improved sexual function specifically in men with decreased NO excretion,³ while another study showed it improved the effects of Viagra in older men after pelvic surgery.⁴ Contrarily, research has also indicated L-arginine is no more effective than placebo as a first-line treatment for impotence.⁵

Arginine in the body requires the assistance of another amino acid, citrulline. As an arginine precursor, citrulline is of particular interest for use in sexual health products. First isolated from watermelon, citrulline may be an alternative to pharmaceutical support for sexual health without the side effects of pharmaceuticals. According to Ahmed, Viagra inhibits an enzyme that helps break down NO, while citrulline works with the body to convert arginine in the liver, thereby improving blood flow by initiating the production of nitric oxide. “The main advantages of using citrulline over arginine is that arginine is broken down in the liver and does not become bioavailable sufficiently to meet the metabolic demands,” Ahmed said. “Since citrulline is converted to arginine, as and when it is needed, it is a preferable nutritive to arginine.”

Despite the discussion of citrulline versus arginine supplementation, L-arginine remains a popularly studied supplement for sexual health, particularly when combined with other ingredients. L-arginine mixed with French maritime pine bark (as Pycnogenol® from Hillside, N.J.-based Natural Health Science) significantly improved male sexual function without any side effects.⁶ And, L-arginine combined with yohimbine may improve erectile function,⁷ as well as enhance desire in women.⁸

Ginseng and Ginkgo biloba have also been studied for their aphrodisiac effects. The ginsenosides in both Asian and American ginseng are believed to enhance libido and sexual performance by relaxing blood vessels and the corpus cavernosum,^9,10 and the botanical increases physical performance, including sexual performance.¹¹ While one study indicated ginkgo was no better than placebo for increasing sexual function,¹² a prior study showed it was 84-percent effective for treating the same disorder, more effectively in women than men.¹³ And, ginkgo combined with muira puama improved women’s frequency of sexual desires, intercourse and fantasies, as well as overall satisfaction with sex life.¹⁴

One of the more well known aphrodisiac herbs is horny goat weed (Epimedium sagittatum), which was shown to improve sexual function and quality of life in patients with chronic renal failure who were on hemodialysis.¹⁵ Epimedium is a featured ingredient in Wally’s Female Sexual Enhancer and Wally’s Horny Goat Weed (for men), both made by Auburn, Calif.-based Wally’s Natural Products.

According to Terry Oquinn, director of sales and marketing at Wally’s, natural remedies for sexual dysfunction or decreased libido are not intended to be compared to Viagra or other pharmaceutical products and should not be promoted as such. “We don’t market [Wally’s Horny Goat Weed] as a Viagra-type product—it’s not,” he said. “It’s meant to enhance and support the male system, while Wally’s Female Sexual Enhancer is meant to support the female system. ... It’s up to the consumer to choose if they want to use prescription drugs or something that’s all natural.”

Maca (Lepidium meyenii) is another well-known herb in the sexual health market. Animal research has shown acute and chronic administration of oral maca supplements significantly improves sexual performance.^16,17 In humans, maca improves sexual desire after eight weeks of treatment,18 and it does not alter serum reproductive hormone levels.¹⁹

One botanical believed to affect testosterone levels, thereby improving sex drive and overall health and wellness, is Eurycoma longifolia Jack, otherwise known as Tongkat Ali. “In addition to increasing overall health and wellness, we have clear evidence of increased testosterone levels,” Lopez said of his company’s Tongkat Ali LJ-100™ product. “If you look at the way testosterone levels decline in men as they age, the impact is not only on sexual vitality but on overall physical health.” In addition to its testosterone-boosting qualities, Eurycoma longifolia Jack (as LJ-100) was shown to increase sexual qualities and sexual activity in animal research.^20,21

Another botanical touted for sex-enhancing properties is Tribulus terrestris. Animal studies have shown Tribulus terrestris improved sexual behavior and had aphrodisiac properties.^22,23Aframomum melegueta and Piper guineense have also been shown to stimulate male sexual behavior in animal research,²⁴ as has Passiflora incarnata Linn.²⁵

One modality of alternative medicine that has some herbal answers for sexual dysfunction is Ayurveda. Ayurvedic products are created to help consumers maintain balance, and thereby overall health, including sexual function. Ayurveda combines ancient knowledge and scientific research “to create very contemporary herbal solutions,” said Grace Ormstein, M.D., Ph.D., medical director and scientific advisor at Himalaya USA. Several ayurvedic ingredients—including ashwagandha, ginger, loosestrife and pellitory—are believed to enhance desire and well-being, with greater effects being seen from combination products.

While consumers want to know about a product’s efficacy, they may be hesitant to ask about sexual enhancement products. “When you see this reticence in the customer at not being able to address the issue, you should be able to gently direct them to the answers,” Ormstein said. “Knowledge, education and listening are important. Try to be attentive as well as gentle—especially in this area because people may become offended easily—and be very discreet.”

Addressing the Issue of Fertility

In the realm of natural products that may improve fertility are several plant-derived ingredients. One example is French maritime pine bark (as Pycnogenol), an antioxidant extract that has been shown to improve sperm quality and function.²⁶ “It may come as a surprise that oxidative stress impairs sperm morphology and function,” said Frank Schönlau, director of scientific communications at Horphag Research, the original developer of Pycnogenol. “The reason for the high oxidation sensitivity lies in the fact that they have considerably higher amounts of polyunsaturated fatty acids (PUFAs) in their membranes than other cells. ... In the case of sperm, the lipid peroxidation makes the membranes dysfunctional. It affects the shape of sperm as well as the sperm-egg interaction, ultimately causing infertility.”

Another antioxidant, lycopene, may also improve sperm quality and thereby increase male fertility. A study of 30 men showed three months of lycopene supplementation improved sperm motility in 57 percent of the men and concentration in 52 percent.²⁷ Additional lycopene research showed the carotenoid improved sperm motility and increased sperm concentration in 66 percent of subjects.²⁸

One botanical studied in the realm of male fertility is maca (Lepidium meyenii). Maca is a powerful energizer that improves physical and mental conditions, as well as increases fertility.²⁹ A human trial of maca supplementation showed the herb increased seminal volume, sperm count per ejaculation, motile sperm count and sperm motility.³⁰ An additional small clinical trial sponsored by LaneLabs showed its macacontaining supplement (Fertil Male™, which also includes HAI, or heated algal ingredient) improved sperm quality, including semen volume, sperm count and sperm morphology.

“I’m hard-pressed to think of other herbs [besides maca] that are useful for fertility specifically, but there would certainly be a lot of nutrients that would be recommended,” said Jennifer Nissen, N.D., manager of nutritional research at LaneLabs. “I don’t think the retailer should steer [consumers] only in one direction. They should offer them a lot of options because a lot of different nutrients are needed to create sperm and maintain fertility. You do need the gamut of the products.”

Vitamins and minerals are integral in maintaining healthy sperm, and supplementation with various micronutrients may be good for improving fertility. Antioxidants in particular seem to be beneficial for male fertility. One study of 30 infertile patients and 20 fertility-proven men implied total antioxidant capacity was a good indicator of sperm motility, and those with decreased antioxidant capacity had impaired sperm function.³¹

Specifically, animal research showed vitamin E protects against oxidative damage in sperm membranes,³² and when combined with vitamin C, it improves sperm quality.³³ Adding selenium to vitamin E benefits sperm concentrations and motility.³⁴ Independently, selenium is required for human sperm maturation and motility.³⁵ Similarly, zinc levels are correlated with sperm function, and infertile men are known to have lower levels of zinc than fertile men.³⁶

Zinc combined with folic acid may be a promising regimen for men looking to improve sperm count. While low folic acid intake is believed to lead to a low sperm count,³⁷ a combination of zinc and folic acid significantly increased total normal sperm count in both fertile and subfertile men after 26 weeks.³⁸

As with folic acid, a deficiency of vitamin B12 may also harm sperm quality. Animal research indicated B12 deficiency during pregnancy led to irreversible damage to the male offspring, including abnormal sperm, low sperm count and decreased motion rates.³⁹ Supplementation with vitamin B6 has been shown in animal research to significantly increase sperm count, induce changes in sperm morphology and improve mating outcome after four weeks.⁴⁰

The vitamin-like compound coenzyme Q10 (CoQ10) also seems to be an indication of sperm quality. Seventeen patients with low fertilization rates were given oral CoQ10 for about three and a half months, after which time a significant improvement was noted in sperm function and fertilization rates.⁴¹ CoQ10, as well as L-carnitine, may also be protective against testicular damage.⁴²

L-carnitine has been studied individually for its role in male fertility. One study in particular indicated seminal carnitine levels might help in the evaluation of male infertility, with L-carnitine values being significantly lower in infertile subjects compared to healthy controls.⁴³ Additionally, researchers noted a positive correlation between L-carnitine and sperm concentration and motility.

Contrary to the positive effects of L-carnitine on fertility, L-arginine may be detrimental. Animal research showed seven days of highdose L-arginine (200 mg/kg/d) supplementation “effectively and reversibly inhibited fertility,” probably due to impaired sperm maturation and hyperactivated sperm motility.⁴⁴

Another supplemental ingredient that has been making waves in fertility circles is soy and its isoflavones. Because soy is a popular ingredient in non-dairy infant formulas, it has been studied for its effects on male sexual development. Research involving female rats indicated those given the soy isoflavone genistein during pregnancy and lactation had offspring with enlarged thymus glands and reduced testosterone concentrations.⁴⁵ Subsequent research also showed reduced testosterone concentrations in the offspring of genistein-fed mothers, as well as smaller testes size and long-term reproductive dysfunctions.⁴⁶

Contrarily, researchers at the Loyola University Stritch School of Medicine reported soy-based infant formula does not cause differences in maturation time, sexual development or fertility in adolescents or adults.⁴⁷ In terms of fertility, animal research has shown genistein’s antioxidant properties exert protective effects on sperm DNA integrity, possibly lending it to the prevention of male infertility.⁴⁸

As purveyors of sexual health products, retailers can enhance their customers’ lives by assisting them in finding the right product. “Retailers are in a unique position to help customers with a variety of quality products for sexual health,” Lee said. “Increase your customers’ comfort levels by creating an easily identified section in your store. Know your products and avoid [those with] extravagant and unsupported claims.”

Consumers are more and more interested in the research behind products, according to Ormstein, and while retailers can help them choose an appropriate product, suggesting a professional consultation is always a good idea. “Always advise [consumers] to discuss things with a doctor,” she said. “Even though [retailers] can cover a lot of things they know about a product, they still leave it up to the customer to make the decisions. ... Education and knowledge of products—both the positive and negative things—are necessary.”

Sexual Health References

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