As fruits become sweeter, are they still the “spokespersons” of health?

Review expert: Li Guangwang, Director of the Natural Education Department of Beijing Children's Palace, senior teacher

I don’t know if you have noticed: fruits have become sweeter in recent years.

This finding is not groundless: taking watermelon as an example, research data from 2009 showed that the total sugar content of seedless watermelon varied between 6.9% and 9.8%. By 2021, the average sugar content of common watermelon varieties was 9%, and the sugar content of the sweetest variety, "All American 2K", reached 13.5%.

Image source: Red China

Fruits are becoming sweeter and more delicious, but the ever-increasing sweetness also makes people worry. Can eating more "purely sweet" fruits still bring health benefits?

Why are fruits getting sweeter? "Cream Strawberry", "Ice Sugar Watermelon", "Sunshine Rose"... These fruit names often make people salivate and also show their "sweetness".

More and more improved varieties of fruits use "sweetness" as their selling point. The "sweet taste" in human genes is being satisfied in various ways by modern technology. So how do fruit farmers and modern technology do this?

01

Fruits also need to be "domesticated"

We all know that many domestic animals are domesticated from wild animals. In fact, fruits are also domesticated from wild plants into crops.

If you have ever watched "Lychees of Chang'an", you will find that from ancient times to the present, humans have never stopped domesticating and selecting fruit varieties. From the early years, there were more than 400 varieties of different flavors, and now there is a general trend of competing for "sweetness". The not-so-sweet Feizishao has fallen to the bottom of the contempt chain, and the more sour black leaves have even been removed from the market and reduced to a low-grade raw material for canned lychees.

Image source: Xiaohongshu

Another example is apples. According to a team from Dalhousie University in Canada, cultivated apples are 3.6 times heavier and 43% less acidic than wild apples. In addition, cultivated apples have 68% less phenolic compounds than wild apples. Phenolic compounds produce bitterness, which means that today's apples taste much less bitter than their ancestors.

02

Genetically improved

The hybrid rice cultivated by Grandpa Yuan Longping has saved us from the trouble of hunger, and this scientific achievement is inseparable from the improvement and influence of crop genes.

We always say that agriculture depends on the weather, but the quality and stability of crop harvests not only affect market price fluctuations, but also affect farmers' income. With the application of modern technology, agricultural producers can use new technologies for gene editing and breeding to cultivate sweeter fruit varieties. By studying the genome of fruits, scientists can understand the composition and nutritional value of fruits, and use gene editing technology to improve the sweetness and taste of fruits.

Image source: Xinhua News Agency

At the same time, because the improved varieties have more advantages, farmers have chosen to plant the same varieties, which in turn affects the fruit varieties we can buy. Before 2015, the market share of Zhangji strawberry was relatively high, but then Hongyan strawberry began to dominate in supermarkets because it has very good comprehensive characteristics, a certain hardness, and a suitable aroma and sugar-acid ratio. It is easy to manage and has relatively stable quality.

This dessert is like a work of art. You must learn how to make it. It also looks great in photos.

03

Technology helps farming

"Technology and hard work" has become synonymous with questioning food safety, but in modern agriculture, if you want to grow high-quality fruits, technology is an indispensable driving force.

Cultivation management has become more sophisticated nowadays. Through reasonable water and fertilizer management and meticulous light and temperature control during the stage of fruit sugar rising, the flavor substances of the fruit can be accumulated more abundantly. Extensive planting methods that only focus on yield but not quality will not produce high-sweetness fruits.

Image source: Xinhuanet

For example, many friends know that light is very important for increasing the sweetness of fruits. Therefore, in order to further increase the sweetness of some fruits, supplementary lights are turned on in orchards at night. The longer the light exposure time, the sweeter the fruit. In addition to these, some new studies have also contributed to the increase in the sweetness of fruits. For example, people have found that applying sucrose solution on the leaves can effectively increase the sweetness of lychees, longans and mangoes. Therefore, many delicious fruits now have "technology and hard work" derived from scientific research results.

Are "purely sweet" fruits still health messengers? For a long time, in most people's minds, "eating more fruits = health", and it is not surprising to have such a mindset:

The Dietary Guidelines for Chinese Residents has been published in five editions. Except for the first edition in 1989, the other four editions have proposed the suggestion of "eating more fruits and vegetables". The latest edition is the Dietary Guidelines for Chinese Residents (2022). The third of its eight principles for a balanced diet is "eat more fruits and vegetables, milk, whole grains, and soy". The specific suggestion for fruits is "eat fruits every day, ensuring a daily intake of 200-350g of fresh fruits. Juice cannot replace fresh fruits."

Image source: People's Daily

As the sweetness of fruits continues to increase, a question gradually arises: are sweetened fruits still healthy?

In 2018, the managers of the Melbourne Zoo in Australia made a new rule: no more fruit for the animals, not even bananas, which monkeys love to eat. Because the red pandas and primates who love to eat fruit not only gained weight, but also had their teeth decayed, the head veterinarian of the Melbourne Zoo believed that the problem was the artificially cultivated fruit that was becoming increasingly sweet.

However, for humans, sweetened fruits do not cause a blood sugar crisis. Although fruits contain a lot of sugar, they also contain more water. The water content of many fruits is over 80%. At the same time, the sugar in the fruit itself is wrapped in cells, plus it is rich in dietary fiber, etc. It takes a long time to digest and enter the blood after consumption, so it will not cause a large blood sugar fluctuation in a short period of time.

Image source |pixabay

But if you turn fruit into juice, it's a different story. In 2013, researchers analyzed the health data of 100,000 people collected between 1986 and 2009 and found that fruit juice intake was positively correlated with an increased risk of type 2 diabetes. On the contrary, according to a meta-analysis, eating all kinds of whole fruits three times a week can reduce the risk of type 2 diabetes by about 7% on average. Therefore, eating more fruit is more beneficial than harmful to the body.

Through observation, we can find an interesting phenomenon, that is, the sweetness of fruits is linked to their prices. This also explains the question of many people, that is, "Where did those simple fruits of childhood go" - they were all eliminated by the market because they were not sweet enough.

At present, we can still say that fruits are healthy foods, but if our love for sweets becomes more and more intense, perhaps one day, with the help of the food industry, fruits will no longer be healthy.