In extreme heat, cooling vegetables and fruits become "overheated" as well.

With temperatures reaching 37-38 degrees Celsius at the beginning of summer, Hanoians have been turning to cooling foods and drinks.

The sudden surge in demand caused food and refreshing drinks to skyrocket in price immediately.

At Nghia Tan, Co Nhue, Dong Xa, Dai Tu markets, and other locations on the morning of May 10th, cooling food items were in high demand despite sharp price increases.

Ms. Lan, a small trader specializing in selling freshwater crabs at Nghia Tan market (Cau Giay district), said that yesterday the price of crabs was only 130,000 VND/kg, but today it has increased to 140,000 VND/kg, with larger ones costing 150,000 VND/kg. Despite the higher price, Ms. Lan said sales are still brisk due to the hot weather.

"Yesterday I sold 80kg of freshwater crabs, and today, by almost 9 a.m., I'd already sold over 50kg. Business is booming, so I've had to hire two more people to help prepare the crabs to keep up with customer demand," she said.

Similarly, according to reporters' observations at the markets, the prices of many types of vegetables with cooling properties have gradually increased. For example: amaranth, jute mallow, and sweet potato leaves have all increased by 1,000 VND/bunch, reaching 6,000 VND/bunch; jute leaves have increased by 2,000 VND/bunch, reaching 6,000 VND/bunch; gourds have increased by 5,000 VND/fruit to 20,000-25,000 VND/fruit depending on the type; fragrant gourds have also increased by 5,000 VND/kg to 25,000 VND/kg; green squash is 15,000 VND/kg, an increase of 3,000 VND/kg; lemons have surged to 40,000 VND/kg...

Not only food items, but also fruits that help cool you down have started to fluctuate in price over the past two days, gradually increasing.

At Dai Tu market, Saigon watermelons are priced at 22,000 VND/kg, an increase of 2,000 VND/kg; seedless watermelons have increased by 5,000 VND/kg to 30,000-35,000 VND/kg depending on the variety; yellow cantaloupe is priced at 60,000 VND/kg, an increase of 10,000 VND/kg; high-quality mandarin oranges are 70,000 VND/kg, and Saigon tangerines are 65,000 VND/kg...

Ms. Nguyen Thi Yen, a street vendor selling fruit on Dai Tu Street, proudly shared that her oranges have been selling very well since yesterday. Customers are buying several kilograms at a time to eat gradually, so the amount of oranges sold has doubled. "Before, I only sold about 60-80 kg a day at most, but when I brought in 150 kg, it all sold out in a single day," Ms. Yen said.

Ms. Yen explained that the increase in fruit prices is partly due to scarcity, and partly because wholesale stores, seeing high demand, automatically raise prices to make a profit. Therefore, vendors at retail markets also have to increase prices accordingly.

"Every year, the hotter the weather gets, the more expensive cooling fruits become. That's the rule. In a few days, around the full moon, prices might be even higher if the weather remains this hot," Ms. Yen predicted.

According to VOV