Institute of Erectile Dysfunction Research - A Comprehensive Resource to Erectile Dysfunction and Impotence - News, Research, Causes, Treatment, Medications, Drugs

High cholesterol isn’t a disease, but if you have it you’re at risk for some serious health conditions.

High cholesterol can manifest with or without symptoms. And the No. 1 danger of this condition is that it clogs arteries, resulting in a condition called atherosclerosis, which reduces blood flow and increases the risk of heart attack or stroke.

But the reduced blood flow caused by high cholesterol also has been linked to sexual disorders.

Dr. Michael Krychman, the executive director of the Southern California Center for Sexual Health and Survivorship, said high cholesterol causes fatty deposits that clog blood vessels leading to the pelvic area. Men with high cholesterol sometimes end up with erectile dysfunction because they are not receiving enough blood flow to the penis, he explained.

“As soon as a man presents with erectile dysfunction, we begin measuring cholesterol and blood pressure,” he said.

Cholesterol is a waxy, fat-like substance found throughout the body that is carried in blood particles called lipoproteins. An excess of cholesterol can lead to a complete blockage of the coronary artery, which will trigger a heart attack.

High cholesterol and its blood flow-restricting mechanisms long have been viewed as a factor in male sexual dysfunction but only recently emerged as culprits in female sexual disorders, Krychman said.

“In the past we used to think if a woman is having sexual problems, she’s frigid, and she needs to go home and have a glass of wine and relax,” Krychman said. “However, there is emerging data associating underlying medical causes with female sexual dysfunction.”

In women, the fatty deposits from high cholesterol may impact lubrication, causing painful intercourse and a lowered libido, said Krychman, who also is director of sexual medicine at Hoag Memorial Hospital.

Men and women who believe high cholesterol may be affecting their sex lives should consult a physician to rule out other causes, Krychman said.

Once cholesterol is determined to be the problem, doctors usually advise patients to seek dietary and lifestyle changes, such as eliminating saturated fat (found in fatty meat and eggs) from the diet, quitting smoking and increasing exercise.

If necessary, doctors may recommend a cholesterol-lowering medication, Krychman added.

Sex sells. I suppose this is why the results of a study entitled “Sildenafil Treatment of Women with Antidepressant Associated Sexual Dysfunction” were reported with great enthusiasm around the world after they were published in the Journal of the American Medical Association (Jama). Yet the study is interesting for a number of reasons.

Sildenafil was originally sold as Viagra. Despite its success in treating men, there has been no equivalent drug for women. In the UK, there is only one licensed drug, Intrinsa, which is used in specific circumstances for female libido problems after gynaecological surgery.

The lack of a “female Viagra” highlights questions over the broader issue of “female sexual dysfunction”. While men with sexual problems frequently respond to drugs, female sexual problems tend to be more complex and far less amenable to pharmacological treatment.

Indeed, as the British Medical Journal noted in 2003, when female sexual dysfunction as a disorder was mooted at an “international consensus development conference” on the subject, 18 of the 19 authors had “financial interests or other relationships with a total of 22 drug companies”. The obvious concern was that the potential for profit was being put higher than the likely benefit to women.

The latest Jama research seems to have found a use for sildenafil in women. Or has it? The women in the trial were experiencing “sexual dysfunction” as a side effect of taking medication – in this case antidepressants.

In order to take part in the trial, the women had to be sexually active before they became depressed, but to have experienced sexual problems for just four weeks – a relatively short space of time.

So how much difference did sildenafil make? When its effect was compared to that of a placebo, there was no difference in the women’s ratings of their desire or arousal and only a small, if statistically significant, effect on orgasm. Forty-three per cent of the women on sildenafil experienced headaches, and both groups had similar scores for depression at the end of the eight-week study.

The logic of using one drug to treat another one’s side effects may sound perverse, but it is frequently applied in the world of medicine. The issue is making sure that each is properly justified.

http://jama.ama-assn.org/cgi/content/short/300/4/395
http://www.bmj.com/cgi/content/full/326/7379/45

Margaret McCartney is a GP in Glasgow.

Want to keep your sex life and your bicycle? New research reveals that men should consider buying a noseless seat.

A innovative study published in this month’s issue of the Journal of Sexual Medicine examined if noseless bike seats would be effective against erectile dysfunction and groin numbness caused by traditional bicycle seats with a protruding nose extension.  The research revealed that men who switched from regular bike seats to noseless saddle seats had improved penile sensation and a reduction in erectile dysfunction (impotence).

Results from this research may be useful for all male recreational cyclists to alleviate perineal discomfort, potential erectile dysfunction and maintain sexual health.

The study tracked 90 bicycling police officers from 5 metropolitan regions in the United States.  The officers were evaluated using traditional saddles and then again after six months of using the noseless bicycle seat.  The noseless saddle seat reduces contact pressure in the perinieal region by cradleing the buttocks and providing freedom in the front.

Before switching seats, 82% of the 90 officers reported penile numbness while cycling.  After switching to the noseless saddle seats, only 27% reported numbness in the groin.

The findings show that use of the noseless saddle resulted in a reduction in saddle contact pressure in the perineal region and significant improvement in penile tactile sensation.  Use of the noseless saddle also resulted in significant increases in erectile function as assessed by the initial evaluation, but there were no significant changes to penile rigidity during sleep.  Officers who reported erectile dysfunction before switching saddles saw an improvement in the longevity of their bedroom encounters.

Most bicycle police officers were able to effectively use no-nose saddles in their police work, and 97 percent of officers completing the study continued to use the no-nose saddle afterward.

Researchers concluded that No-nose saddles are a useful intervention for bicycling police officers alleviating pressure to the groin and improving penis health. Different saddle designs may require some re-learning of ‘how to ride a bicycle,’ but the health benefits to having unrestricted vascular flow to and from the penis and less penile numbness is self-evident.

Erectile dysfunction and impotence affects more than 100 million men worldwide, and more than 600,000 men aged 40 to 69 years seek care annually in the United States. Effective and reliable therapy with PDE-5 inhibitors (such as viagra and cialis) is driving more men to seek treatment. Given the increasing use of the Internet to seek health care information and the social stigma of erectile dysfunction, the Internet is being increasingly used by men seeking erectile dysfunction treatment. However, the safety of these Internet prescription systems is appropriately being questioned because of lack of oversight by state regulation and the lack of perceived safety with the current face-to-face system.

In the August issue of Mayo Clinic Proceedings, researchers from Utah and several colleagues compare the relative safety of two systems — an online prescribing service versus traditional physician consultation — for patients seeking medication to treat erectile dysfunction.

OBJECTIVE: To determine the safety of a US-based, state-regulated Internet system vs a multispecialty primary care system for prescribing phosphodiesterase type 5 (PDE-5) inhibitors for erectile dysfunction.

The Internet is rapidly becoming an important platform for health care communications. This technological advance is driven by the delivery of health care from single to multiple physicians, by direct-to-consumer advertising that empowers patients to make their own health care decisions, and by greater public demand for rapid delivery of health care information.

Unsurprisingly, the increase in demand for electronic health information has evolved in association with direct-to-consumer advertising of pharmaceuticals, which has led the public to seek Internet prescribing. However, prescribing via the Internet has resulted in legal, professional, confidentiality, and safety breaches that threaten public safety.⁴ In response to e-medicine prescribing, the health care industry has appropriately raised serious concerns about the safety of prescribing over the Internet.

The researchers randomly selected 1,000 patient medical records from patients seeking ED treatment from Jan. 1, 2001 to Dec. 31, 2005. Half (500) of these patients used the online prescriber (the e-medicine group), and 500 consulted a physician (the traditional medicine group) for treatment.

Phosphodiesterase type 5 (PDE-5) inhibitors were chosen for this study for several reasons. This drug class is safe and effective for erectile dysfunction, regardless of etiology, with clear contraindications. Further, recommendations for using the drug have been generally established by expert opinion, rather than by evidence, leading to variance in prescribing.

Using statistical analyses, the researchers compared the safety of both approaches — e-medicine versus traditional medicine — in treating patients who have ED. The safety comparisons looked at a number of criteria, including prescription appropriateness, how often the prescribers used a diagnostic tool called the International Index of Erectile Questions (IIEQs) and the level of patient education provided by prescribers.

Evaluating both systems for these safety criteria, the researchers concluded that the e-medicine system “outperformed the traditional system in most of the safety variables tested.” One area the e-medicine system appeared to excel was patient education. The authors noted that 100 percent of the e-medicine clients received written manufacturer product information, and 75.2 percent of e-medicine clients received tailored electronic messages. In comparison, study data showed that no medication instructions were recorded for 51.8 percent of patients who received prescriptions via a traditional physician consultation.

CONCLUSION

A state-regulated e-medicine system was shown to be similar to a traditional multidisciplinary primary care system for all safety end points in prescribing PDE-5 inhibitors. The e-medicine system outperformed the traditional system in most of the safety variables tested. Additional studies of e-medicine vs traditional medicine systems are needed to confirm our results.

See Here for Full Text Original Article: Safety of Prescribing PDE-5 Inhibitors via e-Medicine vs Traditional Medicine

In a study using laboratory animals, researchers found that medications commonly prescribed for erectile dysfunction opened a mechanism called the blood-brain tumor barrier and increased delivery of cancer-fighting drugs to malignant brain tumors.

Tests in rats showed two erectile dysfunction drugs — Schering-Plough’s Levitra and Pfizer’s Viagra — helped carry a chemotherapy drug past the blood-brain barrier, the team at Cedars-Sinai Medical Centre in Los Angeles said.

Viagra (sildenafil) and Levitra (vardenafil) are known as PDE5 inhibitors because they block an enzyme, phosphodiesterase5, which interrupts a series of biochemical events that cause the decreased blood flow of erectile dysfunction. This laboratory rat study, published online ahead of print in the journal, found that similar biochemical interactions in the small vessels of the brain play a major role in the blood-brain tumor barrier, which impedes delivery of anti-tumor drugs into brain tumors. PDE5 inhibitors were found to open the barrier and increase drug transport in this early animal study.

“We chose adriamycin for this study because it is one of the most effective drugs against brain tumour cell lines in the laboratory but it has very little effect in animals and humans because it is unable to cross the blood-brain tumour barrier,” neurosurgeon Dr. Keith Black, who led the study, said in a statement.

“The combination of vardenafil and adriamycin resulted in longer survival and smaller tumour size,” Black said.

Although the researchers exposed the laboratory animals to doses of sildenafil and vardenafil that are comparable to the dose range approved for erectile dysfunction in humans, there were no detectable side effects in the rats, and neither drug increased transport of tracers into normal brain tissue.

The experiments were conducted at Cedars-Sinai Medical Center’s Maxine Dunitz Neurosurgical Institute and published in Brain Research.

MMW Fortschr Med. 2008 Apr 10;150(15):41-3.
[Article in German]

Stadler TC, Becker AJ, Stief CG.

Urologische Klinik und Poliklinik der Universit?t M?nchen, Klinikum Grosshadern. thomas.stadler@med.uni-muenchen.de18510118 [PubMed - indexed for MEDLINE]

J Fam Health Care. 2008;18(2):44.
Scowen P.

Int J Radiat Oncol Biol Phys. 2008 Jul 1;71(3):960; author reply 960-1.
Comment on:

• Int J Radiat Oncol Biol Phys. 2008 Mar 1;70(3):752-9.

Langsenlehner T, Kapp KS, Langsenlehner U.

Curr Urol Rep. 2007 Jul;8(4):281-8.
Jacobsen SJ.

Division of Epidemiology, Department of Health Sciences Research, Mayo Clinic College of Medicine, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA. jacobsen@mayo.edu

This review summarizes recent findings regarding risk factors for benign prostatic hyperplasia (BPH), including new data on hormonal factors, growth factors, comorbid conditions and lifestyle, diet, and exercise as they relate to BPH. In addition, it addresses the design and measurement issues that influence the inference that can be drawn from those studies. Most of the population-based studies on BPH have provided only modest insight into risk factors for BPH. The relationships with circulating levels of steroid hormones and growth factors are still unclear, whereas the association between sexual function and BPH is fairly consistent. Whether this represents a cause and effect relationship or is due to some unobserved confounding factor remains uncertain. There are few data on lifestyle factors that may be amenable to intervention. As future studies aim to address these issues, they should be carried out with rigorous methods, bypassing as many of the methodologic shortcomings of past studies as possible.

Circulation. 2008 Jun 10;117(23):3020-30. Epub 2008 Jun 2.
Diller GP, van Eijl S, Okonko DO, Howard LS, Ali O, Thum T, Wort SJ, B?dard E, Gibbs JS, Bauersachs J, Hobbs AJ, Wilkins MR, Gatzoulis MA, Wharton J.

Adult Congenital Heart Centre and Centre for Pulmonary Hypertension, Royal Brompton Hospital, Sydney Street, London SW3 6NP, UK. g.diller@imperial.ac.uk

BACKGROUND: Impaired endothelial homeostasis underlies the pathophysiology of pulmonary arterial hypertension (PAH). We speculated that PAH patients are deficient in circulating endothelial progenitor cells (EPCs), potentially contributing to endothelial dysfunction and disease progression. METHODS AND RESULTS: We recruited 41 patients with Eisenmenger syndrome (13 with Down syndrome), 55 with idiopathic PAH, and 47 healthy control subjects. Flow cytometry and in vitro assays were used to quantify EPCs and to assess cell function. The number of circulating CD34+, CD34+/AC133+, CD34+/KDR+, and CD34+/AC133+/KDR+ progenitor cells was low in Eisenmenger patients compared with healthy control subjects, and those with Down syndrome displayed even fewer EPCs. Reductions in EPC numbers correlated with New York Heart Association functional class, 6-minute walk distance, and plasma brain-type natriuretic peptide levels. The capacity of cultured peripheral blood mononuclear cells to form colonies and incorporate into tube-like structures was impaired in Eisenmenger patients. Idiopathic PAH patients had reduced numbers of EPCs, and the number of circulating EPCs correlated with invasive hemodynamic parameters in this cohort. Levels of immune inflammatory markers, cGMP, stable nitric oxide oxidation products, and asymmetric dimethylarginine were abnormal in patients with PAH and related to numbers of EPCs. Within the idiopathic PAH population, treatment with the phosphodiesterase inhibitor sildenafil was associated with a dose-dependent rise in EPC numbers, resulting in levels consistently above those found with other therapies. CONCLUSIONS: Circulating EPC numbers are reduced in 2 well-characterized forms of PAH, which also exhibit raised levels of inflammatory mediators. Sildenafil treatment may represent a pharmacological means of increasing circulating EPC numbers long-term.

J Nerv Ment Dis. 2008 Jun;196(6):496-500.
Orr G, Seidman SN, Weiser M, Gershon AA, Dubrov Y, Klein DF.

Department of Psychiatry Sheba Medical Center, Tel-Hashomer, Israel. orrg@netvision.net.il

Late onset dysthymic disorder (DD) in middle-aged and elderly men responds poorly to established antidepressants. Previous studies noted an improvement in mood accompanying sildenafil citrate treatment for erectile dysfunction. We sought to evaluate whether sildenafil’s mood effects were independent of the effect on erectile function. A 6-week open label study was conducted with 20 male participants, aged 41-60 who were diagnosed with DD and who had normal erectile function. Participants were treated with sildenafil citrate 25 mg per day for 6 weeks. The primary outcome measure was the 21-item Hamilton Depression Rating Scale. Depressive and sexual symptoms were also evaluated using self-report questionnaires. Treatment with sildenafil resulted in a significant reduction in Hamilton Depression Rating Scale mean scores: from 14.61 +/- 3.5 at baseline to 6.39 +/- 5.13 at end of study (F(3,51) = 32.52, p </= 0.001). No changes in sexual functioning were detected. Significant improvement was also noted on the self-report measures of depressive symptoms. Sildenafil citrate might have an antidepressant effect on late onset DD, that is not attributable to improvement in erectile function. Possible explanations for this effect are offered. Larger placebo controlled studies are warranted.

Arterioscler Thromb Vasc Biol. 2008 Jul;28(7):1207-8.
Comment on:

• Arterioscler Thromb Vasc Biol. 2008 Jul;28(7):1244-50.

Schleicher M, Sessa WC.

Aging Male. 2008 Jun;11(2):101-6.
Behre HM, Heinemann L, Morales A, Pexman-Fieth C.

Centre of Reproductive Medicine and Andrology, University Hospital Halle, Germany.

Hypogonadism is associated with a range of disease states that have significant effects on morbidity and mortality, and also affect quality of life. The ESPRIT study (Energy, Sexual desire and body PropoRtions wIth AndroGel, Testosterone 1% gel therapy) is a 6-month, multinational, open label, observational study in hypogonadal men being treated with transdermal AndroGel in usual daily clinical practice; 1,700-2,400 patients will be enrolled in Canada, Germany, Central and Eastern Europe, Russia and the Middle East. The main objective will be to evaluate the effect of AndroGel on symptoms of hypogonadism and quality of life as assessed by the Aging Males’ Symptoms scale. Further objectives include evaluating the effect and time to onset of improvement in erectile dysfunction and libido/sexual desire (International Index of Erectile Function), fatigue (Multi-dimensional Fatigue Index) and body composition (waist circumference, body mass index). Subgroup analyses will be performed: <50 years versus > or = 50 years; absence versus presence of metabolic syndrome. The safety of AndroGel will also be assessed. The study population will consist of newly diagnosed hypogonadal men (age > or = 18 years), in whom testosterone deficiency has been confirmed by clinical features and biochemical tests according to international guidelines, who are currently being prescribed AndroGel (testosterone 1% gel, starting dose 50 mg testosterone per day).

BJU Int. 2008 Jul;102(2):259; author reply 259-60.
Comment on:

• BJU Int. 2008 Mar;101(5):581-7.

Sed? J.

N Engl J Med. 2008 Jul 10;359(2):200-1; author reply 201-2.
Comment on:

• N Engl J Med. 2008 Mar 20;358(12):1250-61.

Arap W.

Ten years have passed since the introduction of phosphodiesterase (PDE-5) inhibitors (Viagra followed by Levitra and Cialis) for the treatment of erectile dysfunction. Recently, while watching a televised soccer game with my children, I saw one of the “anniversary commercials.” I, like most parents, exhaled when I did not get any questions about “what exactly is erectile dysfunction?”

However, I began to wonder if Madison Avenue has trivialized a serious medical discussion.

A number of cancer treatments create ED, whether through surgery, radiation therapy or even chemotherapy. One need look no further than management of prostate cancer, bladder and rectal carcinoma, and the management of certain testicular carcinomas to see the scope of the problem. It is estimated that men who undergo prostate treatment, even with newer techniques, have at least a 50 percent risk of impotence. A recent study from Canada, which reviewed a large number of patients treated for rectal cancer, found an astonishing 32 percent of males reported impotence with another 52 percent reporting partial impotence.

Erectile dysfunction is a serious complication from the treatment of these cancers. Once past the initial threat of their diagnosis, patients frequently report ED as one of the most frustrating side effects. Part of this appears to stem from inadequate discussion between patients and their doctors concerning the risks for ED and the likelihood of recovery. This frustration is also seen in the partners of these men, and this spans all age groups; contrary to advertising, intimacy is not confined to the young. Studies have indicated up to half of men aged 70 or older are sexually active.

PDE-5 inhibitors represent the first major step in drug therapy for erectile dysfunction. Nevertheless, these drugs have a number of side effects and may not work at all in a substantial number of patients. Research continues in an effort to define other pathways for drug therapy. And the advent of less invasive surgery and more precise radiotherapy may diminish the risk of ED resulting from these treatments.

So what have we learned in the last decade about erectile dysfunction despite all the marketing sensationalism? Clearly, it is a far more common problem than we knew and it has a significant impact upon men and their partners’ quality of life. Where I hope we are going is that patients and partners share with their treating physicians a free and open discussion about ED as a potential side effect. These discussions are normal, healthy and reasonable. Understanding the risks for ED and the treatments available are the keys to realistic expectations.

Jan Dombrowski, M.D., is medical director and radiation oncologist at Pluta Cancer Center.

Hey, ladies, take a beat before you start pilfering those little blue pills.

That’s the word from Dr. Ira D. Sharlip, a San Francisco urologist and president of the International Society for Sexual Medicine.

Although it may be tempting to act on news that the drug sildenafil, sold as Viagra, may ease the sexual side effects of antidepressant medications, swiping your husband’s stash or turning to Internet sources could be disappointing — or even dangerous.

“Any woman or man who is taking nitroglycerin drugs cannot take Viagra, Levitra or Cialis; it could be fatal,” Sharlip said, referring to other brand-name erectile dysfunction drugs. “I wouldn’t in any way advocate self-medicating with a drug like Viagra.”

New research showing that taking sildenafil significantly improved the ability to achieve orgasm in women suffering from sexual dysfunction caused by antidepressants could be important in a country where 180 million prescriptions for antidepressants are filled each year, mostly for women, and sexual dysfunction is reported in between 30 percent and 70 percent of patients.

However, Viagra didn’t do much for boosting women’s dampened desire, the study showed.

That’s no surprise, Sharlip said. Erectile dysfunction drugs work the same in women as they do in men: by increasing blood flow to the genitals and relaxing the walls of vessels. They don’t directly affect sexual desire. And sometimes, it’s hard to separate the two.

“The percent of women whose sexual dysfunction is due to specific blood flow is very low,” Sharlip said.

Viagra’s effect in women has been disappointing, but a new small study finds those on antidepressants may benefit from taking the little blue pills.  Viagra doesn’t only boost men’s performance in bed, but as it turns out, women too can reap benefits from the magical pill to fight sexual dysfunction. Sexual dysfunction is a common side effect of antidepressants and a major reason why people stop taking medication for their depression. This is particularly problematic given that twice as many women as men are prescribed antidepressants but the most effective drugs used to combat sexual dysfunction in men are not approved for use in women, the authors wrote.

Researchers from the University of New Mexico School of Medicine found that women who took the erectile dysfunction drug sildenafil, a.k.a Viagra, had an improvement in sexual function versus women who took a placebo.  The research involving 98 premenopausal women found Viagra helped with orgasm. But the benefits did not extend to other aspects of sex such as desire, researchers report in this week’s Journal of the American Medical Association.  The researchers said this is the first randomized controlled trial showing that there is a treatment for the sexual dysfunction women experience as a result of taking antidepressants.

“For women on antidepressants with orgasm problems, this may provide some wonderful relief,” said psychologist Stanley Althof, director of the Center for Marital and Sexual Health of South Florida in West Palm Beach, who was not involved in the study. “But it will not improve their desire or arousal.”

The new Viagra findings are based on an eight-week experiment. The 98 women were using antidepressants successfully but were having sexual problems. Their average age was 37.

The women agreed to attempt sexual activity at least once each week. Each time, they took a pill, not knowing whether it was Viagra or a matching dummy pill.

While 72 percent of the women taking Viagra reported improvement or stayed the same on an overall scale, only 27 percent of the women taking the placebo reported improvement or stayed the same.  Some of the women experienced headaches, flushing and indigestion but none of them withdrew from the trial because of side effects.

“These findings are important not only because women experience major depressive disorder at nearly double the rate of men and because they experience greater resulting sexual dysfunction than men, but also because it establishes that selective phosphodiesterase type 5 inhibitors [such as sildenafil] are effective in both sexes for this purpose,” the authors wrote in their study.

July 1, 2008 — Men hoping for some fireworks in their love life this Fourth of July may want to skip the burgers and beer at the barbecue and eat plenty of watermelon.  But according to recent studies, the juicy fruit may be better suited for Valentine’s Day. That’s because scientists say watermelon has ingredients that deliver Viagra-like effects to the body’s blood vessels and may even increase libido.  Watermelon may be a natural Viagra because the popular summer fruit is  in an amino acid called citrulline, which relaxes and dilates blood vessels much like Viagra and other drugs meant to treat erectile dysfunction (ED).

“We have known that watermelon has citrulline,” says Bhimu Patil, PHD, director of the Fruit and Vegetable Improvement Center at Texas A&M University, College Station.  How could watermelon be a natural Viagra? The amino acid citrulline is converted into the amino acid arginine, Patil says. “This is a precursor for nitric oxide, and the nitric oxide will help in blood vessel dilation.”

“The citrulline-arginine relationship helps heart health, the immune system and may prove to be very helpful for those who suffer from obesity and type 2 diabetes,” said Patil. “Arginine boosts nitric oxide, which relaxes blood vessels, the same basic effect that Viagra has, to treat erectile dysfunction and maybe even prevent it.”

While there are many psychological and physiological problems that can cause impotence, extra nitric oxide could help those who need increased blood flow, which would also help treat angina, high blood pressure and other cardiovascular problems.

On hearing about the Texas finding, Irwin Goldstein, MD, editor-in-chief of The Journal of Sexual Medicine, was underwhelmed. Suggesting a man feast on watermelon to boost performance, he says, “would be the equivalent of someone dropping a beer bottle in Minneapolis, where the Mississippi River starts, and hoping to see it make an impact on someone in New Orleans.”

“To say that watermelon is Viagra-like is sort of fun,” says Goldstein. “But to even vaguely hope that eating watermelon will alleviate ED is misleading.”

“The vast majority of Americans produce enough arginine,” adds Goldstein, medical director of Alvarado Hospital Medical Center, San Diego, and clinical professor of surgery, University of California San Diego School of Medicine. “Men with ED are not deficient in arginine.”

Though arginine is required to make nitric oxide, and nitric oxide is required to dilate blood vessels and have an erection, “that doesn’t mean eating something that is rich in citrulline will make enough arginine that it will lead to better penile erections,” Goldstein says.

“Watermelon may not be as organ specific as Viagra,” Patil said, “but it’s a great way to relax blood vessels without any drug side-effects.”

The benefits of watermelon don’t end there, he said. Arginine also helps the urea cycle by removing ammonia and other toxic compounds from our bodies.

Citrulline, the precursor to arginine, is found in higher concentrations in the rind of watermelons than the flesh. As the rind is not commonly eaten, two of Patil’s fellow scientists, drs. Steve King and Hae Jeen Bang, are working to breed new varieties with higher concentrations in the flesh.

In addition to the research by Texas A&M, watermelon’s phyto-nutrients are being studied by the U.S. Department of Agriculture’s Agricultural Research Service in Lane, Oklahoma.

As an added bonus, these studies have also shown that deep red varieties of watermelon have displaced the tomato as the lycopene king, Patil said. Almost 92 percent of watermelon is water, but the remaining 8 percent is loaded with lycopene, an anti-oxidant that protects the human heart, prostate and skin health.

“Lycopene, which is also found in red grapefruit, was historically thought to exist only in tomatoes,” he said. “But now we know that it’s found in higher concentrations in red watermelon varieties.”

Lycopene, however, is fat-soluble, meaning that it needs certain fats in the blood for better absorption by the body, Patil said.

“Previous tests have shown that lycopene is much better absorbed from tomatoes when mixed in a salad with oily vegetables like avocado or spinach,” Patil said. “That would also apply to the lycopene from watermelon, but I realize mixing watermelon with spinach or avocadoes is a very hard sell.”

No studies have been conducted to determine the timing of the consumption of oily vegetables to improve lycopene absorption, he said.

“One final bit of advice for those Fourth of July watermelons you buy,” Patil said. “They store much better uncut if you leave them at room temperature. Lycopene levels can be maintained even as it sits on your kitchen floor. But once you cut it, refrigerate. And enjoy.”

Having regular sexual intercourse may help prevent the development of erectile dysfunction (ED) and impotence. New research published in the July 2008 issue of The American Journal of Medicine reports that scientists have found that men who had intercourse more often were less likely to develop erectile dysfunction and impotence.

The study was conducted over a course of five years with 989 Finish men aged 55 to 75 years. The assessment was based on the 5-item version of the validated International Index of Erectile Function. Men with erectile dysfunction at entry were excluded from the analysis. Researchers found that men who had intercourse less than once per week at baseline had twice the incidence of erectile dysfunction versus those who had intercourse at least once per week. The researchers concluded that the risk of impotence and ED was inversely related to the frequency of intercourse.

Mitigating factors such as age, chronic medical conditions (diabetes, heart disease, hypertension, cerebrovascular disease and depression), body mass index and smoking were included in the analysis of the data.

Men who had sexual intercourse less than once per week had an incidence of erectile dysfunction of 79 cases per 1000. Men who had intercourse once per week hand an incidence of 32 cases per 1000 and the rate dropped to 16 per 1000 for men who had sexual intercourse 3 or more times per week.

The researchers concluded that, “Regular intercourse protects against the development of erectile dysfunction among men aged 55 to 75 years. This may have an impact on general health and quality of life; therefore, doctors should support patients’ sexual activity.”

Reference: “Regular Intercourse Protects Against Erectile Dysfunction: Tampere Aging Male Urologic Study” by Juha Koskimäki, MD, PhD, Rahman Shiri, MD, PhD, Teuvo Tammela, MD, PhD, Jukka Häkkinen, MD, PhD, Matti Hakama, ScD, and Anssi Auvinen, MD, PhD. It appears in The American Journal of Medicine, Volume 121, Issue 7 (July 2008).