Research: Does Watermelon Make You Poop?

Watermelon is one of the summer’s iconic fruits that has a surprising number of health benefits. Watermelon can make you poop because it doesn’t have a lot of fiber, but  92 percent water, which can help you poop.

Watermelon is a sweet treat with plenty of vitamins – and it packs a hydrating punch, too, perfect for beating the heat!

But when you’re making a long trip to a family reunion, a bit of googling might make you think twice about indulging too much in this tasty snack.

Does watermelon help you poop? Does watermelon cause diarrhea? Will you regret it halfway home without a bathroom stop in sight?

On the flip side – there are rumors that watermelon can be great for constipation.

If you’re stuck in the bathroom (or out of it), it’s tempting to think that a sweet, healthy fruit can help ease your pains.

Rest assured, my friends: we’ve done the research, and we’re here to give you the facts.


Watermelon and nutrition

First, though, let’s look at the other reasons why you might want to eat watermelon.

As far as hydration goes, it really can’t be beaten; according to the USDA, 100g of edible fruit contains an average of 91g is pure water. (1)

You’ll also get 112mg of potassium, 8.1g of vitamin C, and 569 IUs of vitamin A.

Yum, right?

While it only clocks in at 30 calories per 100g serving, it does have 6.2g of sugar; this may seem a lot at first – its glycemic index is high for a reason! – but because it’s such a small amount compared to its serving size, scholars Venn and Green say its glycemic load is very low, meaning that it’s not going to cause a blood sugar spike. (2)

A 2014 study shows that watermelon seeds might be able to help treat diabetes-related complications. (3)

Not only is watermelon sweet, but it’s also safe for the people with diabetes in your family.

Onto the nitty-gritty details, though. We did some googling and found many sites that wrote how this delicious fruit was either good for constipation or might cause you diarrhea:


Watermelon, lycopene, and diarrhea

One article, LiveScience, states that one of the antioxidants found in watermelon, if you consume more than 30mg in a day, lycopene, can cause diarrhea. (4)

They linked to a general page of the American Cancer Society – but while the website mentions there is some risk associated with taking too much as a supplement, neither the American Cancer Society nor the lycopene page of MedlinePlus mentions such a side effect.

Moreover, the 30mg daily limit stated doesn’t quite add up – the MedlinePlus page says that 120mg supplements have been taken daily for a year with no adverse side effects.

Where did this rumor start, then?

Numerous studies on the relationship between lycopene and colon cancer show a small number of participants dropped out due to reactions like diarrhea, but this might simply be because of a lycopene allergy.

Emily DeLacey, a registered dietician, has suggested a potential for digestive issues, nausea, or diarrhea with a lycopene sensitivity. However, most of the related information is about tomatoes since they have more lycopene than watermelon per serving. (5)

That’s it, though.

Lycopene isn’t the culprit we’re looking for.


Does watermelon have sorbitol?

This site by Stylecraze is full of misconceptions we’ve already disproved, from lycopene to diabetes, but they also mention that watermelon has sorbitol, sugar-linked diarrhea. (6)

They aren’t the only ones to claim this, either – that watermelon contains sorbitol – but let’s see what the science has to say!

According to MedlinePlus, sorbitol is a sugar alcohol that, while containing about half the calories of regular sugars, can also cause stomach cramps and diarrhea in some people.

If sorbitol were present in watermelon, it might be the reason why it makes people poop.

However, while some fruit contains sorbitol, a 2014 study shows that watermelon doesn’t have any detectable amount of poop-inducing sugar. (7)

Instead, watermelon has sucrose, glucose, and fructose.

Of the three, sucrose is the most likely to cause an issue, but those who experience problems in their bowels most likely have an uncommon sucrose intolerance caused by a lack of sucrase, the enzyme used to break sucrose down in the body.

If you suspect you have a sucrose intolerance, be sure to speak to your doctor.


The water in watermelon

Finally, we have the claims from websites like LittleThings, which boldly claim that watermelon makes you poop.(8)

Their reasoning?

Watermelon has no dietary fiber (which is wrong – it has 1.1g per 100g serving) and a lot of water. Basically, since watermelon is like drinking a glass of water, it’ll help you poop better.

I don’t think we need to explain where the problem with that one is.

Make sure you’re hydrated, and you’ll probably have less problems in the bathroom!


How good is the water in a Watermelon?

Watermelon is a fairly healthy food, although it is mainly water with a bit of sugar.

Its high water content aids in hydration. Vitamin C, beta carotene, and lycopene are all abundant in watermelon.


Negative (side) effects of watermelon

Watermelon contains various ingredients that can produce adverse side effects. Some of the negative effects of this lovely, luscious fruit include(9,10,11,12):

  • Irritable Bowel Syndrome
  • Cardiovascular Conditions
  • Unsuitable for Diabetics
  • A decrease in blood pressure
  • Allergic Reactions
  • Loose Stools
  • Nerve and muscle problems
  • Impotence
  • Insomnia


Other natural ways to relieve constipation

So what are some other natural ways to relieve constipation? has some great recommendations.

The easiest way, as mentioned earlier, is to drink some water, as it’s necessary to making easy-to-pass stools and regular bowel movements.

Eating consistently (don’t skip meals!) and teaching your body to expect a good poop at a specific time every day – like after breakfast or dinner – can also help you pass more pleasantly.

Regular physical activity may also help keep you regular.

Try methods like slowly introducing fiber into your diet. Too much at once can cause cramps and bloat, but getting regular fiber from whole grains, beans, and figs will help move things along.

Fruits with fiber – berries, peaches, apricots, plums, raisins, rhubarb, and prunes – can be an excellent in-the-moment fix, as well.

Pro tip: just be sure to leave the skin on, as that’s where most of the fiber is stored (assuming that the skin is edible).

At the moment, though, the best way to relieve constipation is to talk to your doctor.

Constipation can get serious if left untreated, so be sure to keep a soundtrack of your bowel movements and let your primary care physician know if something is up.

While you’re waiting, though, be sure to avoid greasy, processed foods, as those can hold things up.


Conclusion: Does watermelon make you poop?

All in all, if you’re looking to avoid a pooping problem from overeating soundtrack watermelon, be of good cheer: watermelon will not lead you to the toilet.

If you’re looking for something to alleviate your constipation, the best start is to talk to your general health provider.

Happy pooping!

p.s. you can also find out Does grape juice make you poop and Can watermelon make your poop red?