Watermelon: Nutrition, Health Benefits, Risks, More
Diet & NutritionFood & Ingredients
Explore This Topic

All About Watermelon: A Complete Scientific Guide

By
Updated on April 12, 2024
by

Health Benefits of Watermelon

Uncover the surprising health benefits of watermelon.
Health Benefits of Watermelon

Next up video playing in 10 seconds

When you think of a summertime treat, watermelon may be one of the first things to come to mind. With its sweetness and hydrating effects, watermelon is perfect to enjoy at picnics or by the pool. But there’s much more to this warm-weather staple that you have yet to discover.

Read on to learn more about this famous melon, including its health benefits and how to add more to your plate.

Watermelon Nutrition Facts

Watermelon is considered a water-rich, nutrient-dense food, and the U.S. Department of Agriculture’s (USDA) MyPlate guidelines recommend eating fruit, including watermelon. Watermelon is also low in calories. A 1-cup serving of diced watermelon has the following nutrients:

  • Calories: 46
  • Total fat: 0.2 gram (g)
  • Carbohydrates: 11.5 g
  • Dietary fiber: 0.6 g
  • Protein: 0.9 g
  • Sugars: 9.4 g
  • Water content: 139 g (watermelon is about 91 percent water)
  • Calcium: 10.6 milligrams (mg)
  • Iron: 0.4 mg
  • Magnesium: 15.2 mg
  • Potassium: 170 mg
  • Vitamin C: 12.3 mg (a good source)
  • Vitamin A: 43 micrograms (mcg)

Watermelon is particularly noted for its beta-carotene content, which is a form of vitamin A. Like other types of fruit, watermelon is a good source of vitamin C.

Potential Health Benefits of Watermelon

Although the modern-day watermelon has evolved significantly from its original form, many of its properties haven’t changed.

Boosts Hydration

Watermelon contains about 91 percent water. The Egyptians reportedly placed watermelons in royal tombs to make sure the dead had a source of water, while Hippocrates — the Greek father of medicine — prescribed watermelon to treat heatstroke.

 Staying hydrated is a smart move when it comes to your health because optimal water intake keeps joints lubricated, keeps organs functioning properly, and helps regulate body temperature, among other benefits.

 Eating foods rich in water, such as watermelon, can help you hit your daily hydration goal.

Reduces Blood Pressure

The diuretic effects of watermelon and the potassium content in the fruit can help combat excess sodium intake. With 170 mg of potassium per 1-cup serving, watermelon is just one of the key foods that can help you achieve a healthy potassium intake. The American Heart Association recommends 3,400 mg of potassium per day for men and 2,600 for women.

 Potassium is critical for preventing high blood pressure by aiding the excretion of stored sodium in urine, and it lessens blood vessel tension.
While noted for beta-carotene, watermelon also contains another carotenoid called lycopene. This naturally occurring chemical is red and is only present in red-flesh watermelon varieties. Lycopene itself is known for its potential positive effects on high blood pressure, and it may also help ward off heart disease.

Lowers Cholesterol and Fights Inflammation

Although more studies are needed, some research points to watermelon as a good addition to a plant-based approach to managing inflammation and heart health. Research has established watermelon as one of many antioxidant-rich fruits that may help manage cholesterol, high blood pressure, and other risk factors for cardiovascular disease.

Promotes Healthy Skin

According to a 2022 review, antioxidants such as carotenoids found in watermelon can help protect skin from free radicals and also help protect skin lipids, which may decrease the risk of premature skin aging.

 Additionally, other research suggested that increasing intake of dietary water may help improve skin hydration and elasticity, among other benefits.

Illustrative graphic titled Health Benefits of Watermelon shows icon of a watermelon slices with health benefits such as reduces inflammation, promotes hydration, helps ward off diseases and prevents high blood pressure with Everyday health logo
Everyday Health

Is Watermelon Good for You Sexually?

Some people have claimed that watermelon is “a natural Viagra,” meaning it could help naturally increase your libido and improve your sexual health. Research has noted that the juicy fruit contains lycopene, beta-carotene, and citrulline, which can help relax the blood vessels in ways similar to Viagra.

 Just bear in mind there’s no peer-reviewed, published research that proves this benefit exists, so more studies are needed.

Can Eating Watermelon Help With Weight Loss?

Eating whole, fresh fruit instead of sugary processed treats can help you lose weight over time. While watermelon has less fiber than some other popular fruits like apples and berries, researchers still believe it is a contender in helping you get enough fiber in your day to reduce the risk of high cholesterol and improve regularity. But, according to the Mayo Clinic, the water content in fruits like watermelon can also help you feel full. Watermelon is a smart snack choice or side dish regardless of whether you’re on a diet or want to maintain your weight.

When it comes to weight loss, though, watermelon alone won’t cut it. It’s important to incorporate other fruits and vegetables into your diet in the long term to cut calories while also increasing your intake of important nutrients. You’ll want to avoid fad diets that focus on watermelon as the sole food you eat — these types of diets may make you lose weight temporarily, but you’ll only gain it back once you get back to your normal eating habits.

Are There Any Health Risks to Eating Watermelon?

Unlike processed foods, watermelon is free of long-term health risks for most people. In fact, the low calories and high nutrient content of watermelon make the fruit a beneficial treat for many — including those with type 2 diabetes, who need to monitor blood sugar levels.

According to Oregon State University, although watermelon is relatively high on the glycemic index (GI), with a GI of 76, a serving of watermelon contains about 12 g of carbohydrates.

 That means the fruit has a glycemic load (GL) of about 8, which is low. GL is a scale used to determine whether a food is likely to raise your blood sugar levels when you eat a realistic portion. You can calculate the GL of a food by taking its GI and multiplying it by the amount of carbs per serving and then dividing that total amount by 100.
Another potential risk is a watermelon allergy. While not common, some people who have allergies to ragweed pollen as well as fruits from the gourd family may have an allergic reaction to watermelon.

 Unfortunately, aside from getting a blood test, there’s no way to know for sure if you’re allergic to watermelon until you have a negative reaction after eating it. Some signs include hives, swelling, and breathing difficulties. More severe reactions may be life-threatening.

Other minor side effects from watermelon include upset stomach, abdominal pain, and diarrhea. This is most likely to occur after you’ve eaten too much of the fruit.

How to Select and Store Watermelon

Shopping for a watermelon can be challenging because you can’t see the inside of the fruit until you go home and cut it open. But as a rule of thumb, a watermelon should be heavy — if one seems lighter than the rest, this could mean it has lost its water content and is spoiled. Depending on its size, a mini-watermelon may weigh as little as 2.5 pounds (lb), while a larger variety can weigh 44 pounds or more.

The rind offers other clues to a watermelon’s overall edibility. First, the watermelon shouldn’t have any dents or bruises. No matter what its size, it should also be symmetrically shaped. A healthy watermelon will have a yellow spot on the bottom — this is part of the normal ripening process from when the melon grew on the ground.

How to Cut It

Watermelons are 92 percent water, making them a food that can help you meet your hydration goal, but do you know how to cut them? The Millennial Chef shows you how in this video.
How to Cut It

Next up video playing in 10 seconds

How to Prepare Watermelon

A whole, uncut watermelon should be left at room temperature until ready to use. Always rinse the watermelon rind before cutting. Start by cutting off both ends of a watermelon with a sharpened chef’s knife. Then place the fruit on one side and remove the rind and white flesh with your knife. Finally, turn the fruit on its side and slice the flesh into rounds, and then cut the rounds into cubes if you like, according to your preferred size. This video shows you how to prepare watermelon.

Place any leftover chunks in an airtight container and store in the fridge.

How to Eat Watermelon

Check out some of the following watermelon-inspired recipes you can try at home:

Do You Need to Remove Seeds From a Watermelon?

It’s perfectly safe to eat watermelon seeds.

 They don’t cause any harm and won’t cause anything to “grow” in your stomach. Some people prefer to spit the seeds out while eating, while others simply eat the flesh and seeds together without the hassle. If you don’t want to deal with the seeds at all, look for seedless varieties.

Nutritionally speaking, the only difference between watermelons with seeds and watermelons without seeds lies in the way they’re produced. Seedless watermelons are created with different numbers of female and male flower chromosomes, which make the end product sterile. Therefore, the seedless watermelon, true to its name, can’t produce any seeds. Contrary to popular belief, seedless watermelon is not genetically modified. You’ll still gain the same nutritional benefits found inside the seedless watermelon flesh as you would with a regular seeded watermelon.

The Takeaway

Watermelon is more than a refreshing summertime treat; it's packed with water and nutrients, which may help lower blood pressure and cholesterol. Studies suggest that this juicy fruit can even aid in skin health and hydration. Next time you're feeling hungry on a hot day, reach for some watermelon to keep cool and take care of your health.

Common Questions & Answers

Is it okay to eat watermelon every day?
While it’s technically safe to eat watermelon every day, it’s best to eat a variety of fruits and vegetables for optimal nutrition. The MyPlate nutrition guidelines from the U.S. Department of Agriculture recommend two servings of fruits and three servings of vegetables daily.

Watermelon, like other fruits and vegetables, is considered to have a low energy density. This means that a serving has fewer calories than other choices that have a high energy density, such as packaged sweets. While watermelon may contribute to a healthy diet for weight loss, other nutritious foods, such as complex carbs, healthy fats, and lean protein, can help as well.

Multiple studies have evaluated watermelon’s health benefits. Watermelon, in the form of its whole flesh, juice, and extract, has been associated with a lower risk of high blood pressure and may help with cholesterol management.
Watermelon has almost 10 grams (g) of sugar per 1-cup serving but is still considered to have a low glycemic load. Eating watermelon in moderation isn’t considered a diabetes risk, and it can even be a safe sweet treat if you do have the condition.
Watermelon can be a healthier alternative to satisfy a sweet tooth compared with ice cream, cakes, and other processed foods. Just be aware that the fruit has a high water content — eating too much right before bed may increase urination.
Meet Our Experts
See Our Editorial PolicyMeet Our Health Expert Network
Roxana Ehsani, RDN

Roxana Ehsani, RD

Medical Reviewer

Roxana Ehsani, RD, is a Miami-based licensed dietitian-nutritionist, board-certified specialist in sports dietetics, and media spokesperson, consultant, and content creator for food and nutrition brands. She is an adjunct instructor for sports nutrition at Virginia Tech in Blacksburg.

Ehsani appears as a food and nutrition expert for television stations across the nation and in national publications, including Runner's World, Women's Health, Glamour, and more, and is a contributing writer for EatingWell. She has a strong background in sports nutrition and has worked with professional, Olympic, collegiate, and high school teams and individual athletes, whom she sees through her private practice. 

See full bio

Kristeen Cherney, PhD

Author
Kristeen Cherney, PhD, is a freelance writer, essayist, author, and poet with more than 15 years of health writing experience for digital platforms such as Healthline, The Mighty, and LiveStrong. She’s covered nutrition, women’s and children’s wellness issues, as well as specialized topics ranging from diabetes and thyroid disease to anxiety, depression, asthma, allergies, and skin conditions.

With a doctorate in English (rhetoric and composition), Dr. Cherney focuses her academic scholarship on the intersection between disability and literacy. She also holds a Master of Arts in English and a Bachelor of Arts in communication.

Cherney has contributed to the books The Wiley Handbook on Violence in Education: Forms, Factors, and Preventions, Composing in Four Acts: Readings for Writers, and Georgia State University's Guide to First-Year Writing, as well as to scholarly journals like Praxis, the Journal of Teaching Writing, and the Journal of Dracula Studies.

Cherney enjoys running, meditating, hiking, and paddleboarding.
See full bio
See Our Editorial PolicyMeet Our Health Expert Network
EDITORIAL SOURCES
Everyday Health follows strict sourcing guidelines to ensure the accuracy of its content, outlined in our editorial policy. We use only trustworthy sources, including peer-reviewed studies, board-certified medical experts, patients with lived experience, and information from top institutions.
Resources
  1. Watermelon, Raw. U.S. Department of Agriculture. April 1, 2019.
  2. Trinklein D. Watermelon: A Brief History. University of Missouri. July 17, 2020.
  3. The Importance of Hydration. Harvard T.H. Chan School of Public Health.
  4. How Potassium Can Help Control High Blood Pressure. American Heart Association. June 5, 2023.
  5. Lycopene. MedlinePlus. January 30, 2023.
  6. Zuraini NZA et al. Promising Nutritional Fruits Against Cardiovascular Diseases: An Overview of Experimental Evidence and Understanding Their Mechanisms of Action. Vascular Health and Risk Management. November 23, 2021.
  7. Michalak M. Plant-Derived Antioxidants: Significance in Skin Health and the Ageing Process. International Journal of Molecular Sciences. January 6, 2022.
  8. Palma L et al. Dietary Water Affects Human Skin Hydration and Biomechanics. Clinical, Cosmetic and Investigational Dermatology. August 3, 2015.
  9. Watermelon May Have Viagra-Effect. Texas A&M University. July 1, 2008.
  10. Weight Loss: Feel Full on Fewer Calories. Mayo Clinic. January 12, 2024.
  11. Higdon J et al. Glycemic Index and Glycemic Load. Oregon State University. March 2016.
  12. Food Allergy: Symptoms and Causes. Mayo Clinic. December 13, 2023.
  13. Watermelon. Britannica. March 1, 2024.
  14. Facts and FAQs. Watermelon.org.