Some men may experience better erectile function during the summer months, and there has long been an old wives’ tale that tries to explain the matter. Sure, summertime may just be a period of the year when men feel naturally friskier, or perhaps the exposure to more sunlight and fresh air helps to explain this penis health change. But folk medicine has for centuries encouraged men who have difficulties with their erections to partake of abundantly available watermelon during the summer season. And it seems that these old wives may have been on to something.

Citrulline

Why would this delicious fruit be a possible aid in erectile health? After all, it’s 92% water, leaving very little else to make an erectile performance contribution.

But one of the things that it does contain a lot of is an amino acid called citrulline (or L-citrulline). A typical 4-ounce serving of watermelon contains about 150 milligrams of citrulline, which is pretty significant.

Okay, so watermelon has a lot of citrulline. Why should this matter? Well, because citrulline gets converted into L-arginine, another amino acid. And this particular amino acid is a precursor to nitric oxide. And why does that matter? Because nitric oxide plays a big role in helping blood vessels, including penile blood vessels, to expand. During the erectile process, the penis needs to be able to accommodate a great increase in blood. This increased blood flow fills the spongy tissue in the penis, and it is this filling that causes the penis to expand and harden. If the penile blood vessels are opened all the way, it is much easier for the rush of blood to get in and do its job.

A study

A recent study has looked at the possibility of using citrulline in conjunction with other erectile function medications to try to improve efficacy. Published in the journal Sexual Medicine, it is entitled “Oral L-citrulline and Transresveratrol Supplementation Improves Erectile Function in Men with Phosphodiesterase 5 Inhibitors: A Randomized, Double-Blind, Placebo-Controlled Crossover Pilot Study.”

A little background is helpful in understanding this study. First, phosphodiesterase 5 inhibitors (usually abbreviated PDE5i) is the name given to the most commonly used drugs for treating erectile dysfunction, which are effective in up to 84% of patients. When these drugs do not work, additional therapies are called for usually in conjunction with the PDE5i pills – but these additional therapies are not medications but things like penis pumps or injections.

This study looked at using both citrulline and another oral medication (resveratrol, which occurs naturally in grapes and wine) in conjunction with men for whom PDE5is were not providing the desired effect. All of the 13 men who completed the trial showed improved scores on the tests used to measure erectile function.

Although this was a small pilot study, it does add some heft to the argument that watermelon may be of use in treating erectile issues – although again, it doesn’t mean that watermelon by itself can do the trick.

And while watermelon is an excellent source of citrulline, there are many others foods that also provide citrulline, including garlic, onions, liver, cucumbers, chickpeas, peanuts, soybeans, salmon and even dark chocolate.

Treating erectile dysfunction can require a multifactorial approach, and it is usually easier to treat if overall penis health has been maintained. One way to help address this is by regularly using a superior penis health creme (health professionals recommend Man 1 Man Oil, which is clinically proven mild and safe for skin). Seek out a crème which contains the amino acid L-arginine, which as this article mentions, can be a big help in nitric oxide production. It also helps if the crème contains a range of vitamins that can more easily deliver their benefits from topical application, such as vitamins A, B5, C, D and E.