Watermelon has only 6.2 grams of sugars per 100g. It won’t spike blood sugar levels, as its main sugar type is fructose. Even people with diabetes can eat reasonable amounts.
How much sugar can we eat a day?
The maximum recommended daily intake of added sugar is up to 5% of total calorie intake. Therefore, we shouldn’t consume more than 25 grams of added sugar a day on a 2,000 calorie diet.
This is extremely difficult to meet, though. Sugar interferes with the reward system of the brain, affecting eating behavior.[1,2]
Consuming sugar from whole fruits isn’t a problem. Certainly, eating reasonable amounts of fruits like watermelon is healthy. Sugar naturally present in fruit juices can be too much, though.
What’s the sugar content of watermelon?
Watermelon is low in calories, as it’s mostly water. Most calories come from sugars. Watermelon contains negligible amounts of protein, fat, fiber, or other carbs.[3]
Watermelon has 6.2 grams of sugar per 100g. So, you can’t possibly consume too much sugar by eating watermelon:
- a cup contains only 9.2 grams of sugar
- a large slice contains about 18 grams of sugar.
How much sugar in watermelon juice?
Keep in mind that commercial watermelon juices, drinks, or cocktails may contain high amounts of added sugars. For instance, an 8 fl oz glass of commercial watermelon juice may contain 20 grams of extra added sugars.
You better avoid them. Especially, if you want to lose weight. Added sugar is bad for our health. It’s just empty calories. Sugar contains no vitamins or minerals.
Moreover, you better consume the whole fruit, instead of the fruit juice. Fruits also contain dietary fiber. Fiber is crucial for good health. High fiber intake lowers the risk of developing coronary heart disease, stroke, hypertension, diabetes, obesity, and certain gastrointestinal diseases.[4]
Hence, you better consume whole fruits, instead of their juice. Only lemon juice is low in sugars.
Do other fruits have more sugar than watermelon?
In fact, most popular fruits contain significantly more sugar than watermelon! Only berries, lemon, and avocado have significantly less sugar than watermelon.
| sugar (grams per 100g) | |
| dates | 66 |
| raisins | 65 |
| mango | 13.7 |
| apple | 13 |
| banana | 12.2 |
| pear | 9.7 |
| orange | 9.2 |
| kiwi | 9 |
| melon | 9 |
| papaya | 7.8 |
| watermelon | 6.2 |
| cranberries | 4.3 |
| lemon | 2.5 |
| avocado | 0.3 |
Common berries low in sugar are strawberries, blueberries, raspberries, blackberries, and cranberries.
Certainly, all dried fruits (e.g. dates, raisins) have a much higher sugar content. We should consume only small amounts.
What type of sugar is in watermelon?
Watermelon has 3 types of sugar: fructose, glucose, and sucrose:
- fructose is 54% of the total sugar content of watermelon
- glucose is 26%
- sucrose in 20%
Fructose has to be metabolized by the liver first. In contrast, glucose is instantly available to the body. Thus, watermelon won’t spike blood sugar levels. It has a low Glycemic Index of 48.[5]
Can people with diabetes eat watermelon?
Furthermore, as watermelon is mainly water and contains a small amount of sugar, it has a pretty low Glycemic Load of 7. Thus, eating reasonable amounts of watermelon doesn’t significantly raise blood sugar levels!
Even people with diabetes could safely consume a serving of watermelon in order to satisfy their sweet tooth. In fact, the American Diabetes Association has listed watermelon as a safe fruit for people with diabetes. It’s a healthy dessert.[6]
Certainly, you should consult your physician before changing your diet.
Watermelon seeds have no sugar!
Did you know that you can eat watermelon seeds? Not only are they edible, but also, they have a superior nutritional value.
In contrast to watermelon, watermelon seeds contain no sugar. They’re mainly protein and polyunsaturated fatty acids (the healthy kind of fat). Moreover, watermelon seeds are packed with minerals, such as iron, magnesium, phosphorus, zinc, manganese, and potassium!
Therefore, eating watermelon seeds with watermelon flesh further lowers the total glycemic index of the meal.
Health benefits of watermelon
Watermelon has many health benefits, as it’s particularly high in lycopene. This compound has potent antioxidant properties
Lycopene seems to have therapeutic effects and be beneficial on many diseases, such as cancer, cardiovascular disorders, diabetes, high blood pressure, and macular diseases.[7,8]
Also, watermelon can help us lose weight, as it’s low in calories and keeps us full for a long time. Hence, the best time to eat watermelon is before a high-calorie meal. It regulates total energy intake.
Besides watermelon, pink grapefruit, guava, papaya, and tomato are the richest foods in lycopene.
