Foods That Help Erections: Do Watermelon, Pomegranate, Pistachios and Nuts Really Work?

One evening a video comes up on the phone: “A man who eats these three foods will never need medication.” Watermelon, pomegranate and pistachios are listed, and the comments are full of hope. For a man struggling with erections for some time the idea is appealing: no examination is needed. One question remains: “Do these really work?”

Erectile dysfunction means being unable to achieve or maintain an erection firm enough for intercourse. Some of the foods promoted online as a “natural erection remedy” have genuinely been studied, but most studies are small and short. This article looks at what the watermelon, pomegranate, pistachio and nut studies found, the evidence on diet, weight and physical activity, and the drawback of relying on a food while putting off assessment.

Can a food really affect erections?

An erection is a vascular event: with stimulation, the blood vessels of the penis relax and blood fills the tissue. Nitric oxide plays a part in this relaxation. Citrulline in watermelon is converted in the body to arginine, a precursor of nitric oxide; nuts contain arginine and antioxidant compounds.

A plausible mechanism does not show that a food improves erections in the amounts normally eaten. Four questions are worth asking of a study:

• How many people took part? A few dozen people give only a first impression.
• Was there a comparison group? Without a placebo group, the source of improvement is unknown.
• What was given? The food itself, or a concentrated form of one of its components?
• What was measured, and for how long? A few weeks of questionnaire scores do not show lasting improvement.

Does watermelon help erections?

The watermelon claim rests on citrulline. In an Italian study, 24 men with mild erection problems had a placebo for one month, then 1.5 grams of citrulline a day for another. The erection hardness score rose from 3 to 4, meaning normal, in 2 men (8.3%) on placebo and in 12 men (50%) on citrulline. The authors add that the effect was weaker than that of prescription erection medicines. Three points matter before applying this to watermelon:

• Watermelon was not what was given: the participants took pure citrulline, and no group ate watermelon.
• The amount: one analysis measured about 1.9 grams of citrulline per kilogram of watermelon flesh, by fresh weight. The study's daily amount corresponds to roughly 800 grams of flesh, eaten every day for a month. That much watermelon also raises sugar and calorie intake.
• The design: the study was single-blind, everyone took the placebo first and citrulline second, and follow-up lasted one month. Such a design cannot separate out the effect of expectation.

The available data do not show that eating watermelon corrects an erection problem.

What did the pomegranate juice study find?

Of these foods, pomegranate juice is the one tested in a placebo-controlled, double-blind study. In the United States, 53 men with mild to moderate erection problems were followed in a crossover design: one drink for 4 weeks, a 2-week break, then the other drink for 4 weeks. Of the 42 men reporting improvement on a global assessment questionnaire, 25 did so after the pomegranate juice period.

The difference did not reach statistical significance (p=0.058). The authors describe the work as a pilot study. Even the best-designed food study could not show that “pomegranate juice improves erections”.

What did the pistachio study show, and what did it not show?

This study was carried out in Ankara. A group of 17 married men with erectile dysfunction for at least 12 months ate 100 grams of pistachios a day for 3 weeks. The mean total score on the International Index of Erectile Function (IIEF) rose from 36 to 54.2, and cholesterol values also improved.

Several points limit interpretation:

• There was no control group: the same men were measured before and after the diet. How much of the improvement came from pistachios and how much from expectation is unknown.
• Small and short: 17 men and 3 weeks say nothing about whether the change lasts.
• The amount is not a recommendation: 100 grams a day describes the study. Pistachios are high in fat and dense in calories, and eating this amount regularly may add to weight gain.

The result is a preliminary observation, not evidence of a treatment.

Do walnuts, almonds and hazelnuts strengthen erections?

Controlled data on nuts come from the FERTINUTS study in Spain. Of 83 healthy men aged 18–35, 43 added 60 grams a day of mixed walnuts, almonds and hazelnuts to their usual diet for 14 weeks, while a control group of 40 ate no nuts. In the nut group, scores for orgasmic function and sexual desire rose relative to the control group. The erectile function score, however, did not differ significantly between the groups, and blood nitric oxide levels did not change either.

The participants were young men without erection problems, and this was a secondary analysis of the trial; the research was partly funded by a nut industry body. The authors state that the results cannot be generalised to men with erectile dysfunction. Here too, 60 grams describes the study and is not a recommendation.

What emerges when the whole diet is considered rather than a single food?

The evidence strengthens when the focus moves from one food to the overall diet:

• Fruit intake: in a US study of 25,096 male health professionals, 35.6% of participants reported erection problems over 10 years. The risk was 14% lower in those with a high fruit intake.
• Mediterranean diet score: in an analysis of 21,469 men from the same population, men under 60 with the highest score had a risk about 22% lower than those in the lowest group.
• Intervention data: in Italy, of 65 men with metabolic syndrome and erectile dysfunction, 35 followed a Mediterranean-style diet and 30 a control diet. After 2 years, the erection score had reached the normal range in 13 men in the first group and 2 in the control group.

The first two studies are observational; men who eat well may differ in other ways too, so they do not prove cause and effect. The third is small. Even so, they point in the same direction: a diet based on vegetables, fruit, whole grains, legumes, nuts and olive oil. Watermelon, pomegranate and pistachios can have a place in such a diet, but not as a treatment in themselves.

How much difference do weight loss and physical activity make?

In an Italian study, 110 obese men aged 35–55 who had erectile dysfunction but no diabetes or high blood pressure were split into two groups. One group of 55 received detailed advice on reducing calories and increasing physical activity; the other 55 were given general information.

After 2 years, the mean body mass index in the advice group had fallen from 36.9 to 31.2, and weekly physical activity had risen from 48 to 195 minutes. The erection score rose from 13.9 to 17 in this group and did not change in the other. Erectile function returned to the normal range in 17 men in the advice group (about 31%) and in 3 in the control group.

Sustained weight loss and regular activity restored normal function in about a third of these men; in the rest they were not enough alone. The European Association of Urology (EAU) guideline also recommends starting lifestyle changes and risk factor modification before, or at the same time as, treatment for erectile dysfunction.

Why can relying on a food and waiting be a problem?

The real cost of food videos is lost time. An erection problem is often a sign of a cause involving vascular health, diabetes, hormones, medication or anxiety. In Italy, erectile dysfunction was found in 147 of 300 patients with coronary artery disease shown on angiography. Of these 147 patients, 67% reported that the erection problem had begun before their heart symptoms, with a mean interval of 38.8 months. The data come from one centre and rely on patients' accounts.

Waiting for months with watermelon or pistachios can delay blood sugar, blood pressure and cholesterol checks. The link between erectile dysfunction and cardiovascular disease is covered in a separate article on this site. The risks of pastes and capsules sold as “herbal”, and how prescription erection medicines work, are covered separately too.

When should you see a doctor?

Assessment by a urology and andrology specialist is advisable if:

• The erection problem has lasted for several months or is getting worse
• It is accompanied by diabetes, high blood pressure, high cholesterol, smoking or excess weight
• There is a family history of early cardiovascular disease
• You notice a marked fall in sexual desire or morning erections
• The problem continues despite changes in diet and physical activity
• You have used a sexual enhancement product of unknown content
• You have chest pain, breathlessness or palpitations on exertion (for persistent chest pain, call 112 or go to an emergency department without delay)

The available studies on watermelon, pomegranate, pistachios and nuts are small, short or uncontrolled, and none shows that these foods treat an erection problem. The stronger evidence concerns the overall diet, weight and physical activity, and these steps do not replace an assessment. Assoc. Prof. Dr. Zülfü Sertkaya practises urology and andrology in Istanbul; assessment of erectile dysfunction is individualised and carried out in confidence.

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