[Column] The best ways to enjoy summer watermelon

Summer is the season of watermelon, but it’s also the season of dieting for weight loss. However, you don’t have to worry about getting fat by eating watermelon. One hundred grams of watermelon provides only 31 calories of energy. If you eat a kilogram of watermelon at a time, that’s about the equivalent calories of a bowl of rice. Because of its sweet flavor, it’s easy to think that watermelon contains a lot of sugar. However, watermelon has only 5.1 grams of sugar per 100 grams, which is less than half the sugar content of apples (10.6 grams) and grapes (11.9 grams). The reason why watermelon is so low in calories is that more than 90 percent of its flesh is water. This is why it’s a good idea to eat watermelon often to stay hydrated during the summer when you sweat a lot. In addition, most of the sugars in watermelon are fructose, which has a low glycemic index. When dissolved in water, fructose exists in a form that has a stronger sweetness at lower temperatures. This is the scientific principle behind the phenomenon that makes watermelon taste sweeter and more delicious when it’s chilled in the refrigerator.

Lycopene is what gives ripe watermelon its red color. Watermelon contains 40 percent more lycopene than a raw tomato. You don’t need to cook watermelon to increase the absorption of this antioxidant. The lycopene in watermelon is present as its cis-isomer, which is more easily absorbed by the body. Watermelon is also rich in the amino acid L-citrulline, which has been linked to heart health benefits. One kilogram of watermelon contains about 2 grams of L-citrulline. L-citrulline dilates blood vessels, reduces blood pressure, and may even help with erectile dysfunction in men. Many people take L-citrulline as a pre-workout supplement because they think it will improve their performance, but studies on athletes have shown minimal benefits. No studies have shown that eating watermelon lowers blood pressure or prevents cancer. However, knowing that it contains lycopene, L-citrulline, and other nutrients may make you feel a little better about cooling off with watermelon.

These days, it's not uncommon to see videos of people slicing watermelon in style. But when it comes to slicing fruit, safety should be the priority. A 2020 U.S. study found that half of all avocado-related hand injuries occurred between April and July. While there are no studies on the frequency of watermelon-related hand cuts, it's still easy to get hurt if you're not careful. When slicing watermelon, make sure your cutting board and the surface of the watermelon are dry to prevent slipping. Cutting the watermelon in half, dividing it into smaller pieces, and then removing the skin is the least risky way to avoid cutting yourself. Dicing and refrigerating it in an airtight container is less likely to cause bacterial contamination than wrapping the watermelon in plastic wrap. I’m eager for the hot, humid days of summer to end, but I also wish I could keep enjoying the refreshing satisfaction of pulling a cool watermelon from the fridge for as long as I want.

Jeong Jae-hoon is a food writer and pharmacist. He covers a variety of subjects, including trends in food, wellness and medications. This column was originally published in Korean in Joongang Ilbo on July 18, 2024. – Ed.