“Oranges cause internal heat, while oranges and grapefruits reduce internal heat”? Can we still eat oranges safely?

Rumor: "Oranges cause internal heat, while oranges and grapefruits reduce internal heat"

Now is the time when citrus fruits are on the market. As for tangerines, we have always been told not to eat too many, as they can cause internal heat. However, we do not have this worry about oranges and grapefruits, which are said to reduce internal heat.

Rumor analysis: Not true.

Oranges are not guilty, and oranges and grapefruits are not magical either. The so-called "heat" symptoms such as ulcers, mouth sores, and swollen gums after eating oranges are just caused by "high sugar content" and "eating too much".

Eating oranges in the winter while heating is on is a good idea. However, many people are worried that eating oranges will cause "inflammation". Some people have experienced dry mouth, sore throat, oral ulcers, swollen gums and other discomforts after eating oranges. Are these symptoms caused by oranges?

Image source: Xiaohongshu user

Not really.

It’s all because of “high sugar content” and “eating too much”

Oranges are one of the fruits with a high sugar content, especially varieties such as sugar oranges, which have a pure sweet taste. The sugar content is higher than other varieties such as ordinary oranges, tangerines, and grapefruits, reaching 13.06 grams per 100 grams [1-2].

Consuming a large amount of high-sugar, high-salt food at one time will cause the oral and throat mucosa to fall into a high osmotic pressure environment, which will then cause cell dehydration, dry mouth and even ulcers. This is the same as eating too many salty (high-salt) melon seeds and peanuts during the Chinese New Year, which causes dry throat and ulcers at the corners of the mouth.

Some friends pointed out that although the sugar content in oranges is a bit high, the sugar content in Guoguang apples and Korla pears can reach 13.3 grams/100 grams and 13.4 grams/100 grams respectively. That's why we don't get a sore throat when eating them.

There are actually three reasons behind this:

First, it is very easy to eat too many oranges in one go.

Although the sugar content of apples and pears is not very low, few people can eat 4 or 5 apples or pears at a time, right? However, during the Chinese New Year, it should be easy to eat 4 or 5 oranges while chatting with friends and relatives. Some people even eat several kilograms of sugar oranges a day. Therefore, from the perspective of total amount, eating oranges is more likely to cause excessive sugar intake than eating apples and pears, and of course it is more likely to cause damage to the oral and throat mucosa.

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Second, the discomfort caused by fruit acid.

Some people experience gum pain and discomfort after eating too many oranges. This may be due to the organic acids in oranges, the so-called "teeth are sour". Although oranges do not taste sour, their organic acid content is higher than that of apples. For example, the total acid content of navel oranges is 0.92%, and even sugar oranges have a total acid content of 0.37%, while the total acid content of ordinary apples is usually around 0.2% to 0.5% [2~3]. If you eat a large amount at one time, it is possible that your gums and oral mucosa will be irritated.

Third, oranges may indeed contain pro-inflammatory ingredients.

Consuming large amounts of high-sugar foods can easily increase the risk of inflammation in the body. Other studies have found that citrus fruits do contain some pro-inflammatory proteins [4], which may be one of the reasons why people develop oral ulcers and sore throats after eating a lot of oranges. Although the relevant study used mandarin oranges, the researchers suggest that wide-skinned citrus fruits (i.e., fruits with a certain gap between the peel and the flesh, making them easy to peel) also contain this ingredient, and similar symptoms may occur when consumed in excess.

It can be seen that whether eating oranges will cause sore throats, mouth ulcers, etc. is mainly related to the amount of intake. According to the "Dietary Guidelines for Chinese Residents", the daily fruit intake should be 200-350 grams, which is about the amount of 2-3 medium-sized oranges. If you eat sugar oranges, it is best not to eat more than 10 a day. Eating them "by the pound" is definitely excessive.

Which one is better among tangerine, orange, grapefruit and mandarin orange?

In addition to tangerines, other members of the citrus family, such as oranges, grapefruits, and tangerines, are also delicious. How should we choose between them? In addition to choosing according to taste preferences, we can also understand the small differences between them and choose according to our own health needs.

1. If you want to lose weight, choose grapefruit

The calories and sugar content of grapefruit are relatively low in the citrus family. If you need to lose weight or control blood sugar, you can choose grapefruit.

2. If you want to supplement vitamin C, choose oranges

Oranges usually have higher vitamin C content than tangerines and grapefruits. If you don't eat much fresh fruits and vegetables and want to supplement vitamin C for antioxidants, oranges are a better choice. Unfortunately, the highly praised lemons do not have an advantage in vitamin C content among citrus fruits. Don't bite lemons to supplement vitamin C in the future!

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3. If you want to share easily, choose orange

Oranges are a very suitable fruit for sharing. They are not only sweet, but also easy to peel without getting your hands all sticky with juice. During the Chinese New Year and other festivals, people share them together to avoid discomfort such as dry mouth, swollen gums, etc. caused by one person eating too much.

4. Everyone likes the standard one, choose tangerine

The sugar content, vitamin C and other nutrients of tangerines are between those of tangerines and oranges. The taste is also very similar to tangerines and oranges, but they are usually easier to peel than oranges. They are a standard choice that everyone likes.

How to eat oranges more comfortably and healthily?

If you just prefer oranges and are afraid that you can't stop eating them, but don't want to have any problems, you can try the following tips:

1. Rinse your mouth immediately after eating

By gargling, you can promptly remove the sugar attached to the oral and throat mucosa, improve the high osmotic pressure environment, reduce damage to mucosal cells, and reduce the probability of oral ulcers and throat and gum pain.

2. Pair with other fruits or healthy foods

If you are worried that you can't stop eating oranges, you can add some apples, pears, peaches, etc., which are high in water and dietary fiber and low in sugar, to increase satiety. Or you can add healthy foods such as sugar-free yogurt and plain nuts to enrich nutrition and reduce the intake of oranges.

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3. Choose oranges with low sugar content

my country has a wide variety of orange varieties. We can choose small-leaf oranges, Sichuan red oranges, and other varieties that have lower sugar content than sugar oranges and honey oranges (8.8 g/100 g and 9.8 g/100 g, respectively) [1]. However, it is not easy to successfully identify different varieties of oranges, so we should give priority to the first two methods.

Finally, I have to remind everyone: eating too many oranges may not only cause discomfort in the mouth and throat, but may also turn you into a Minion (excessive intake of carotene accumulates in the body). Although it is harmless and will heal in a few days, it is not what we want to look bad. It is still better to eat well and in moderation!

Looking in the mirror of rumors

The symptoms of what we commonly call "getting angry" are similar to "inflammatory response" in medicine, mainly including toothache, mouth ulcers, skin acne, sore throat, red and swollen eyes, etc. Excessive consumption of any food can cause discomfort, and different people react differently to food. Some people may be more sensitive to certain fruits, including tangerines, oranges and grapefruits. Eating these fruits in moderation and maintaining a diverse diet can ensure that the body obtains a variety of necessary nutrients while avoiding discomfort caused by excessive intake of a single food.

References

[1] Yang Yuexin. Standard Edition of Chinese Food Composition Table (6th Edition/Volume 1)[M]. Peking University Medical Press, 2018.

[2] Wu Xiaohong, Chen Baohong, Li Xiaohua. Determination of total acid and total sugar in citrus fruits[J]. Food Research and Development, 2012, 33(9):144-146.

[3] Analysis of sugar and acid composition and content in different varieties of apple fruit[J]. Journal of Northwest Agriculture and Forestry University (Natural Science Edition), 2011, 39(10): 163-170.

[4] Wang Xiaoli. Evaluation of the pro-inflammatory effects of water-soluble lychee protein extract and citrus Citsh1 protein[D]. Hubei., 2015: Huazhong Agricultural University.

Author: Wang Lu, registered dietitian

Review丨Zhang Yu, researcher at the Chinese Center for Disease Control and Prevention, national health science expert