Properties and Benefits of Watermelons

In summer the days are long and hot, the sun is scorching and we feel as if we are slowly melting even when we are relaxing besides the pool with a refreshing beverage in our hands. When temperatures seem to go through the roof, many of us feel like all our energy is being drained slowly and there seems to be no remedy for it.  Fortunately, there is: a great energy-boosting fruit, nutritious and hydrating called a watermelon. Originating in Africa, watermelons are high in water, low in calories and a good source of vitamin C, B vitamins, essential minerals and important antioxidants such as lycopene.

What is watermelon?

The watermelon (Citrullus lanatus) is a fruit, more exactly a berry. It belongs to the Curcubitaceae family, meaning it is related to gourds, squash, zucchini and pumpkin, but also cucumbers and melons in general. There are actually quite a few watermelon varieties in addition to the green rind, pink-red, sweet flesh watermelon we all know and love. Some varieties are bitter to the taste, other quite bland, reminiscent of some gourds or cucumbers. The fruit is known to occur naturally in the wild and is extensively cultivated.

Watermelon benefits

What does watermelon look like?

The watermelon is a large fruit that can easily grow to over half a meter in diameter. On the exterior it has an inedible, green rind with a specific color pattern: elongated, dark, green stripes over a lighter-colored green. Depending on the cultivar, the stripes may be smooth-looking or look similar to lightning bolts or as if they resulted from watercolor painting. Some varieties have a darker green rind without any distinguishable pattern.

The watermelon plant is a vine that creeps along the ground which means the fruit also rests on the ground until it’s ready to be harvested. The portion of the rind in contact with the ground is usually discolored, not green but cream-colored or a slight earthy yellow hue. Between the inedible green rind and flesh there is also a light green-whitish, partially edible portion of rind, usually a few centimeters thick. On the inside, the fruit is not divided in any way and there are usually a lot of small, brown seeds. Seedless watermelon varieties also exist.

What does watermelon taste like?

The most common watermelon variety has a delicious, pleasantly firm, extremely juicy and sweet pink to dark red flesh. The best watermelons have a honey-like sweetness to them. However, this is but one variety. It may come as a surprise, but the interior of a watermelon can also be yellow, orange, light green or white and have either a bitter or bland taste, similar to other tasteless gourds or cucumbers. These varieties are less popular, yet just as nutritious as our all-time summer favorite, the common red-flesh watermelon. The part between the rind and inner flesh is also edible and contains important antioxidants with benefits for cardiovascular health.

watermelon small

Watermelon seeds and rind

The unripe seeds are a milky white color and soft, slightly chewy, but edible. The ripe seeds are a luscious, dark brown with a hard outer shell and milky white on the inside. Watermelon seeds are edible, but they pose certain health risks and are best avoided because they may accidentally obstruct breathing or cause complications for diverticulitis sufferers and, in rare cases, bowel obstruction. The raw rind is inedible, but boiling or pickling it can render it edible.

Watermelon and dehydration

Why are watermelons so dearly recommended for consumption during summer? First of all, the fruit is approximately 91.45% water and helps us stay hydrated. It further contains 6.20 g of natural sugars which combat hypoglycemia and boost energy levels. When the temperatures are high during summer, we sweat excessively in order to keep cool which means we lose more water than usual. Water is essential for practically every body function so it is imperative that we replace all that has been lost as soon as possible. And a great way to do this is by eating watermelon and other foods rich in water.

Eating watermelon will not only help prevent and reverse dehydration as a result of high temperatures, but because the fruit is so sweet, chances are you will eat more of it and thus increase your water intake for good kidney and cardiovascular function. Excess water is quickly eliminated and the slight diuretic effect of the fruit is great for our kidneys, helping them get rid of many toxins this way. Even more, eating watermelon when it’s hot outside can help prevent fainting because the high water content of the fruit helps increase blood volume.

Most people believe that dehydration is not a serious issue which is why they take this matter lightly. But the truth is that when we sweat excessively our body loses not only water, but also important minerals and vitamins. As a consequence, many people end up fainting or have little to no energy and previous medical conditions, especially cardiovascular problems, often worsen with low fluid intake.

Nutritional Facts watermelons

Watermelon nutrition facts and benefits

Some of the benefits of watermelon are a result of a low energetic value. Watermelon has 30 kcal/100 g and around 261.5 kcal/wedge (weighing around 285 g). This low calories content makes it an ideal food for weight loss and weight management.

Other nutritional facts per 100 g:

  • 7.55 g of carbohydrates (per 100 g)
  • 6.20 g of sugar
  • 0.61 g of protein
  • 0.15 g of fat
  • 0.4 g of fiber
  • 91.45 g of water

100 g of fresh watermelon contains good amounts of beta-carotene and lycopene and vitamins A and C. Beta-carotene is a carotenoid with vitamin A activity. Vitamin A is good for eyesight, improving vision acuity and supports the health of mucous membranes at the level of the eyes, nose, mouth, throat, lungs and stomach, with benefits for immunity. Vitamin C is a strong antioxidant and anti-inflammatory nutrient which holds many benefits, from boosting immunity and reducing arthritis inflammation and pain to reducing gum bleeding, tooth loss and helping prevent respiratory infections such as the flu.

Because the fruit is also incredibly delicious, you will most likely eat more than 100 g and thus have a far greater intake of the vitamins and the benefits that comes with it. Watermelon is also rich in lycopene, a highly potent phytochemical responsible for the red color of the fruit flesh. The antioxidant is also found in high amounts in tomatoes, red carrots, pink grapefruit and especially gac fruit (see benefits of Gac fruit).

Together with vitamin C and beta-carotene, lycopene is scientifically proven to reduce cardiovascular disease risks. Basically, if you eat watermelons, these compounds will reach your bloodstream and clean the blood vessels of free radicals, exerting a positive antioxidant action. Lycopene being an antioxidant, it has anticancer properties, adding to the reasons why you should eat watermelon.

Though the amounts are not significant, watermelon also contains vitamins B1, B2, B3, B5, B6 and choline which bring modest benefits for digestion and brain and nervous system health. The fruit further contains small amounts of calcium, iron, magnesium, manganese, phosphorus, potassium and zinc, essential dietary minerals with a tonic action and benefits for cardiovascular and bone health as well as energy metabolism. Magnesium and potassium in particular are our heart’s best friends, regulating blood pressure.

When it’s hot outside and you feel low on energy or feel like you are about to faint, remember that eating a wedge of watermelon can help counteract dehydration and its symptoms and provide important dietary minerals and essential vitamins for a revitalizing effect. Watermelon seeds are also a great source of important nutrients, especially dietary minerals and are ideal for keeping in good health. However, remember to eat them carefully and in limited amounts. If you have conditions that prevent you from eating seeds like watermelon seeds or fruits with seeds like kiwifruit, avoid them altogether. See article on the benefits of watermelon seeds.

Watermelons are especially great if you have children. Because they are incredibly sweet and juicy, there isn’t a child who will say no to a refreshing slice of fruit or even a large glass of juice. The fruit can easily replace a sweet snack and you will have the certainty that both you and your child stay hydrated in hot weather. However, it is not wise to eat too much of anything.

Watermelon side effects

1) Diuretic properties. One of the side effects of watermelon is its high water content which makes it a diuretic fruit. When eaten in unreasonably high amounts and too frequently, it can promote diuresis and deplete the body of essential nutrients.

2) Can cause gastroenteritis. If the fruit is dirty, contaminated or spoilt, it can cause gastroenteritis. Irrigation with contaminated water can spread infection on the rind. Cutting the fruit then distributes the pathogenic agents onto the flesh. If the flesh has an off-smell or is too mushy or piquant or sour to the taste, then the fruit may be spoilt.

Watermelon and diabetes

While diabetics can eat just about anything, including fruits like watermelon, they are advised to keep intake low to avoid raising their blood sugar levels too much. Watermelon has a high glycemic index (72), meaning it’s likely to cause blood sugar spikes. But if eaten in small amounts, preferably not every single day, it can be safely incorporated into a diabetic diet without causing long-term damage as it has a low glycemic load (around 5). What this means is that small servings of the fruit don’t actually affect blood sugar too much. Find out more about the topic in the article: can you eat watermelon with diabetes?


Overall, watermelons are incredibly delicious and nutritious, not to mention versatile. For instance, watermelon rind is highly appreciated in many cuisines, where it is cooked and served as a dish of itself or pickled and served as a side dish. In more traditional cuisines, the rind is made into jam. And did you know that watermelon seeds were found in the tomb of Pharaoh Tutankhamen himself? The fruit was also depicted in numerous Egyptian hieroglyphs which is consistent with findings that suggest watermelon cultivation dates back to ancient Egyptian times.

This post was updated on Tuesday / October 6th, 2020 at 7:26 PM