1. Helps you stay hydrated

Staying hydrated is important for your body to function properly.

Body temperature regulation, normal organ function, nutrient delivery to cells, and alertness are only some of the bodily processes that rely on adequate hydration.

Eating foods with a high water content may help give your body the water it needs to function properly.

Watermelon comprises 92% water, making it a great choice for daily water intake.

Furthermore, due to its high water content, this melon has a low calorie density — in other words, very few calories for its total weight.

Eating foods with low calorie densities, such as watermelon, may aid weight management by keeping you feeling full for longer.

2. Packed with nutrients and beneficial plant compounds

Watermelon contains a variety of nutrients, including potassium, magnesium, and vitamins A and C. It’s also relatively low in calories, containing just 46 per cup (152 grams).

Here are the nutrients in 1 cup (152 grams) of raw, diced watermelon:

  • Calories: 46
  • Carbs: 11.5 grams
  • Fiber: 0.6 grams
  • Sugar: 9.4 grams
  • Protein: 0.9 grams
  • Fat: 0.2 grams
  • Vitamin A: 5% of the Daily Value (DV)
  • Vitamin C: 14% of the DV
  • Potassium: 4% of the DV
  • Magnesium: 4% of the DV

Watermelon is also a rich source of citrulline, an amino acid that may improve exercise performance.

Plus, it boasts antioxidants, including vitamin C, carotenoids, lycopene, and cucurbitacin E.

These compounds help combat free radicals, which are unstable molecules that may damage your cells if they accumulate in your body. Over time, this damage may lead to conditions like diabetes, heart disease, and cancer.

3. May have anticancer effects

Several plant compounds found in watermelon, including lycopene and cucurbitacin E, have possible anticancer effects.

While study results are mixed, lycopene intake may be associated with a lower risk of some types of cancer, such as prostate and colorectal cancers .

Lycopene is believed to work by lowering blood levels of insulin-like growth factor (IGF), a hormone that promotes cell division. Notably, cancer forms when cell division becomes uncontrollable.

Additionally, cucurbitacin E may inhibit tumor growth by promoting the autophagy of cancer cells. Autophagy is the process by which your body removes damaged cell.

4. May improve heart health

Several nutrients in watermelon may support heart health.

Heart disease is the leading cause of death worldwide. It’s worth noting that lifestyle factors like diet may lower your risk of heart attack and stroke by reducing your blood pressure and cholesterol levels .

Studies suggest that lycopene may help lower cholesterol and blood pressure. It may also help prevent oxidative damage caused by high cholesterol levels .

Watermelon also contains citrulline, an amino acid that may increase nitric oxide levels in your body. Nitric oxide helps your blood vessels expand, which lowers blood pressure.

Other heart-healthy vitamins and minerals in watermelon include magnesium, potassium, and vitamins A, B6, and C.

5. May reduce inflammation and oxidative stress

Inflammation is a key driver of many chronic diseases.

The combination of antioxidants, lycopene, and vitamin C in watermelon may help lower inflammation and oxidative damage.

In one study, rats fed watermelon powder to supplement an unhealthy diet developed less oxidative stress and lower levels of the inflammatory marker C-reactive protein than those in the control group.

Additionally, an 8-week study gave 31 people with obesity and high inflammatory markers 500 mg of vitamin C twice daily. They showed a significant decrease in inflammatory markers compared with the control group .

As an antioxidant, lycopene may also delay the onset and progression of Alzheimer’s disease. However, more research is needed.

6. May help prevent macular degeneration

The watermelon compound lycopene may have benefits for your eyes.

Age-related macular degeneration (AMD) is a common eye problem that can cause blindness in older adults.

Lycopene’s role as an antioxidant and anti-inflammatory compound may help prevent and inhibit AMD, though research is limited .

One test-tube study that treated eye cells with lycopene found that it decreased the capacity of inflammatory markers to damage cells.

Keep in mind that human research is necessary.

7. May relieve muscle soreness

Citrulline, an amino acid found in watermelon, may improve exercise performance and reduce muscle soreness.

It’s also available as a supplement.

One review found that regular intake of citrulline for at least 7 days improved aerobic performance by increasing the body’s production of nitric oxide.

This compound helps expand blood vessels so that your heart doesn’t need to work as hard to pump blood through your body.

What’s more, some evidence suggests that watermelon itself — not just citrulline — may aid your body after exercise.

One older study gave athletes plain watermelon juice, watermelon juice mixed with citrulline, or a control drink. Both watermelon drinks led to less muscle soreness and quicker heart rate recovery than the control drink.

Still, more research is needed.

8. May aid skin health

Vitamins A and C, which are found in watermelon, are important for skin health.

Vitamin C — either when eaten or applied topically — helps your body make collagen, a protein that keeps your skin supple and your hair strong.

One review found that a higher intake of vitamin C from food and/or supplements may decrease your chances of developing wrinkles and dry skin.

Vitamin A is also important for healthy skin since it helps create and repair skin cells.

In one review, animals with vitamin A deficiency had poorer wound healing than those fed a nutritionally complete diet.

Bear in mind that further human studies on watermelon specifically are needed.

9. May improve digestion

Watermelon contains plenty of water and a small amount of fiber, both of which are necessary for healthy digestion.

Fiber helps keep your bowels regular, while water moves waste through your digestive tract more efficiently .

One survey in 4,561 adults found that those with low fluid and low fiber intakes were more likely to experience constipation. Nonetheless, other factors may have played a role.