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Although research is still in its preliminary stages, some studies suggest that watermelon may be a viable substitute for Viagra in people with erectile dysfunction.

The advent of Viagra and other erectile dysfunction (ED) treatments revolutionized the world of sexual medicine. No longer did men with certain medical conditions or age-related ED have to resign themselves to unsatisfying sex lives.

However, ED drugs do not work for every man. Some men experience side effects, while the drug is unsuitable for others, such as men with certain types of chest pain and heart disease.

For men who cannot take Viagra, watermelon is a safe alternative that is unlikely to cause serious side effects. Learn more with this article.

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Citrulline naturally occurs in watermelon and it may support better erections.

Watermelon is a natural source of citrulline. Citrulline is an amino acid that may support better erections.

Viagra works by increasing blood flow to the penis, allowing a man to more easily get an erection when he is aroused. Citrulline may do the same thing, although it works in a different way to Viagra.

Preliminary research suggests that the body may convert citrulline to another amino acid, called arginine. Arginine converts to nitric oxide. Nitric oxide opens the blood vessels wider, increasing blood flow to the penis and improving erections.

Because watermelon is mostly water, the highest concentrations of citrulline come from concentrated watermelon juice.

Men who want to try watermelon as a natural Viagra may find better results with watermelon juice.

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Research suggests watermelon may be a safe alternative to Viagra.

Research into the effects of citrulline and watermelon is relatively new. Most studies have been small or looked only at animals. As such, it is too early to say there is conclusive proof that watermelon can act as a natural Viagra.

Preliminary research is promising, and there are few or no risks associated with consuming watermelon. This means that most men can safely try watermelon juice or citrulline supplements as an alternative to Viagra.

A 2011 study followed 24 men with mild ED. The men took a placebo for 1 month. For another month, they took a citrulline supplement.

Just two of the men taking a placebo saw their erections return to normal hardness levels. But half of the men who took citrulline experienced improvements that brought their erections to normal hardness levels.

Men who took citrulline also had more sex, averaging 1.37 sessions of intercourse per month before treatment, and 2.3 per month after treatment. None of the men experienced side effects.

A 2013 study gathered data on rats with ED due to low blood flow to the penis. This disorder, called arteriogenic erectile dysfunction, is a common cause of erectile problems in humans.

Rats that took a citrulline water supplement experienced improvements in erectile function compared with rats that received a placebo and rats that underwent surgery on their blood vessels. This finding suggests that citrulline may improve blood flow, potentially improving erections.

A 2014 study evaluated male rats treated with watermelon flesh extract. Rats who consumed watermelon were more likely to mount females and start intercourse. This increase in libido, the study’s authors concluded, suggests that watermelon might also be a viable treatment for ED.

There were no serious side effects, and the rats that ate watermelon extract did not experience an increase in weight.

Research published in 2017 sought to further understand the role of citrulline and arginine in erectile function. Researchers measured levels of both amino acids in 122 men with ED.

They found lower levels of one or both amino acids in men with ED, particularly in men with arteriogenic erectile dysfunction. This suggests that increasing levels of either citrulline or arginine, or both could improve erectile function.

Men should note that watermelon is likely not as effective as Viagra, and may not work for men who have not been able to get an erection with Viagra.

This is because watermelon increases blood flow to the penis, just like Viagra. If another issue, such as nerve damage or a serious relationship problem, is causing a man’s ED, merely increasing blood flow may not be much help.

While research on animals often applies to humans, this is not always the case. Studies finding positive results in rats may point toward the value of citrulline in treating ED, but they do not prove that it works in humans.

The United States Food and Drug Administration (FDA) have not approved citrulline as a treatment for ED. Many more trials are necessary before doctors can determine whether or not citrulline works.

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Unless a person has an allergy or diabetes, watermelon can be safely consumed.

Watermelon is considered safe, even in large quantities. Unless a man has an allergy to watermelon, he can safely consume it.

Men with diabetes should discuss with their doctors how much watermelon they can safely consume. Watermelon and other fruits can raise blood sugar levels; so eating large quantities may be unsafe for some people with diabetes.

Watermelon is low in calories, but overconsumption of any food can lead to weight gain. It is unwise to eat large quantities of any food, especially if doing so causes gut pain or uncomfortable feelings of fullness.

No research has found any serious side effects associated with watermelon in healthy men or animals. As such, it is okay to try watermelon as a Viagra alternative, or even to use it alongside Viagra.

The benefits of watermelon come from citrulline. Using watermelon in a way that maximizes citrulline intake can increase the benefits.

A 2005 study found that red watermelon was slightly lower in citrulline than yellow or orange varieties. Watermelon rind has higher concentrations of citrulline than the fruit’s flesh. There were no significant differences between seeded and seedless watermelon varieties.

To maximize citrulline intake, people can try blending watermelon rind in a smoothie.

Some supplement manufacturers, such as those found here, also sell citrulline supplements. Though these products can increase citrulline intake, the FDA do not evaluate the safety or effectiveness of these supplements.

Viagra is a safe, effective option for most men. For men who prefer to avoid drugs or who cannot use Viagra, watermelon is one of many possibilities.

Men should talk to a doctor to work out their best treatment option. Sometimes, a combination of natural and medical remedies can help.