Sugar-free is not sugar-free. Is there a health hazard if you drink it for a long time？
[Editor’s note]On June 29th, 2023, Reuters reported that two people familiar with the matter revealed that aspartame, one of the most common artificial sweeteners, will be officially listed as a "potentially carcinogenic to humans" by IARC, an international cancer research institution under the World Health Organization (WHO) in July.
On March 15th, 2023, The Paper published a series of special topics on "Sugar-free in the world", including "Sugar-free in the world ③ Sugar-free is not sugar-free. Will there be health hazards if you drink it for a long time? ",the manuscript discusses the related health risks of sugar-free drinks, and the old article is reissued.
"Sugar-free and healthier" seems to be becoming an accepted concept by more people, so sugar-free drinks with sugar substitutes are becoming more and more accessible, and more and more health-seeking consumers are willing to pay for them.
The The Paper reporter noted that in recent years, the health risks of sugar-free drinks have repeatedly been on the hot search list, which has caused public discussion: "Why are sugar-free drinks more harmful than sugar-containing drinks?" "What are the hazards of drinking sugar-free drinks for a long time?"
Why do sugar-free drinks with sugar substitutes become the "target" of health disputes? Are sugar-free drinks healthier or more unhealthy?
From sugar to sugar-free, the nutritional concept of China residents has changed.
Broadly speaking, sugar is a kind of carbohydrate, which exists not only in foods with sugar such as white sugar and brown sugar, but also in common foods such as steamed bread, rice, cakes and fruits. The so-called sugary drinks or sugar-free drinks generally depend on whether there is additional sugar added.
As early as 1989, China published the Dietary Guidelines for China Residents for the first time, and revised them in 1997, 2007 and 2016. The latest published guideline in 2022 is the fifth edition. The constantly updated and changing guidelines are not only suggestions for healthy diet for the people, but also reflect the cognitive changes of various nutrients in nutrition circles and the public over the years.
Source: China Nutrition Society official website
Take adding sugar as an example. Although the 2007 edition mentioned "drink plenty of water every day and choose drinks reasonably", there was no requirement for sugar intake. According to the meeting record of the special conference of the Ministry of Health at the time of China Network, experts explained: "In terms of dietary structure, our sugar intake is very small, not as much as that in the West." However, in the 2016 edition and the 2022 edition, the guidelines both emphasize "sugar control and alcohol restriction", and propose to control the intake of added sugar, with the daily intake not exceeding 50g, preferably below 25g.
"When I was in college, an old professor said in a public nutrition course that we China people eat very little sugar, so we don’t have to consider it." Gu Zhongyi, director of the Beijing Dietitians Association and master of public health in Tsinghua University, said in an interview with The Paper that the 1997 version of the dietary guidelines did not mention the content of "adding sugar". In 2007, the domestic guidelines mentioned the issue of "reasonable exercise and controlling obesity". Since then, the American dietary guidelines mentioned "adding sugar" in the dietary ingredients to be quit in 2010, and the World Health Organization has also issued guidelines on controlling the intake of "free sugar".
The admiration for sugar-free drinks has not been sustained. In recent years, the health risks of sugar-free drinks have been frequently mentioned.
Drinking sugar-free drinks for a long time may also have health hazards.
It is not uncommon to find public research results about the health hazards of sugar-free drinks.
On February 28th this year, a study published in the British journal Nature Medicine suggested that erythritol, a commonly used artificial sweetener, may be related to heart disease. Researchers at Cleveland Medical Center in the United States conducted a preliminary study among 1157 people who had undergone heart disease risk assessment and had 3-year outcome data. By analyzing the chemicals in the blood, the team observed that the compound levels of various artificial sweeteners (especially erythritol) were related to the increased risk of heart disease and stroke in the future during the three-year follow-up.
The team also conducted another experiment and found that erythritol had an effect on the increased risk of thrombosis. After eight healthy volunteers ingested 30 grams of erythritol beverage, the researchers examined their plasma levels and found that the erythritol levels of all volunteers continued to increase, exceeding the threshold of increased blood coagulation risk in 2-3 days. The researchers believe that this discovery may indicate that the increase of erythritol level is related to the increased risk of thrombosis. However, they also pointed out that the incidence of vascular risk factors in the center of the array in this study is high, and it is still necessary to confirm whether similar results can be observed in the longer-term follow-up of obviously healthy subjects.
A large study published in JACC)2020 also showed that artificial sweeteners may be related to the risk of cardiovascular disease. After a 10-year follow-up of more than 100,000 subjects, compared with those who don’t drink artificial sweeteners, the people who drink artificial sweeteners the most (the median is 176.7 ml per day) have a 32% higher risk of cardiovascular disease. This study also suggests that sugar substitutes are not a healthy substitute.
In addition to increasing the risk of cardiovascular disease, sugar replacement may also affect people’s blood sugar level. In August 2022, a research paper published in Cell magazine pointed out that some sugar substitutes will not only affect the microbial composition of human body, but also affect the molecules in peripheral blood circulation, and then affect the individual’s tolerance to glucose.
Research papers in Cell magazine
In December 2019, a paper published in Diabetes Care, a journal of the American Diabetes Association, analyzed the data of nearly 200,000 people who have been tracking for more than 20 years, and also pointed to the diabetes risk behind sugar substitutes. The results show that changing from sugary drinks to artificial sweeteners and zero-calorie/low-calorie sugar substitutes has not changed the risk of diabetes in these people. The best choice is to drink tea, coffee and milk without sweeteners directly.
Research paper in Journal of American Heart Association
How to understand the health risks of drinking sugar-free drinks for a long time?
Earlier, Professor Mu Yiming, chief physician of the Department of Endocrinology, First Medical Center of the General Hospital of the Chinese People’s Liberation Army, also said in an interview with the media: "Many studies have found that if sugar-free drinks are drunk for a long time, if sweeteners are added, such as sucralose, aspartame, xylitol, etc., these sweet sugar substitutes are not essentially different from sugary drinks in causing diabetes. On the contrary, these sugar-free and sweet drinks may be more harmful than drinking sweet and sugary drinks in causing diabetes and cardiovascular diseases. "
For the mechanism of health risks of sugar-free drinks, Mu Yiming introduced in an interview with The Paper. At present, the academic circles are not very clear about the exact mechanism behind it. Only from the current research or literature, there are several generally accepted explanations. One of them is that although the sweetness of sugar-free drinks is not really added with sugar, but with synthetic or natural sweeteners, the taste of sweetness itself will stimulate the brain, make people more appetizing and eat more things, including other sweets, which will lead to weight over time. In addition, when a person starts to eat more sweets, it will also lead to poor insulin responsiveness to glucose for a long time, and finally lead to insulin resistance, which will be manifested as an increase in blood sugar.
It is worth mentioning that, on the social platform, diabetic patients can judge the influence of a drink on blood sugar and health by measuring the blood sugar value at different times after drinking sugar-free drinks. In this regard, mother Yiming emphasized that sugar-free drinks have no energy or low energy, and drinking them once does not cause blood sugar to rise like sugar-containing drinks. At present, the emphasis on the potential risks of sugar-free drinks is mostly based on the premise of long-term heavy drinking. "Long-term is in years, and the current research is also based on years." Drinking once in a while does not mean that there is no risk for a long time.
Gu Zhongyi expressed a similar view. He pointed out that whether sugar-free drinks are healthy or not depends mainly on their long-term effects, such as diabetes and other chronic diseases. A person’s health is affected by many factors. From the perspective of overall human health intervention, sugar-free drinks may be only a small aspect, and the impact is not particularly great. Whether a drink is healthier or less healthy depends on what kind of drink it is compared with, and it also involves many differences in dosage, crowd, attention to different aspects and so on.
Can the public still drink sugar-free drinks facing controversy?
"I haven’t eaten sweet food or drunk drinks for such a long time. What do you recommend me to drink?"
As an expert in the field of endocrinology in China, Mother Yiming sees many diabetic patients every year, and many of them also ask whether they can drink sugar-free drinks. The answer given by mother Yiming is usually: you can taste it occasionally, but don’t drink it for a long time. You must be self-disciplined.
Mother Yiming told reporters in The Paper that human beings are getting more and more kinds of food, and their understanding of health and diseases is becoming more and more comprehensive, and everyone’s understanding of sugar is becoming more and more full. "Do you think sugar is bad? The brain will faint after leaving sugar for a few seconds. "In fact, whether a food or nutrient is healthy or not is often divided into two, and the main problem behind it is the dose.
"From a safety point of view, sugar-free drinks are fine, but it is best to drink white water and not drink any sweet drinks." Gu Zhongyi once gave such a suggestion in a popular science article on nutrition.
Gu Zhongyi said that adding sugar-free drinks instead of sugar will not make people’s blood sugar rise immediately, nor will it stimulate insulin as claimed by some people, and even lower blood sugar. Compared with drinks with common added sugar, this kind of non-nutritive sweetener drinks are safe and can be drunk by diabetics, which is judged from the perspective of the lesser of two evils and can be used as a substitute for the transition to a healthy diet. However, it should not be ignored that for some people, drinking sugar-free drinks for a long time will also affect blood sugar levels.
Gu Zhongyi believes that the scientific community will continue to study the health problems of sugar-free drinks. For the public, in the face of constantly updated research results, it is not necessary to be too nervous, just follow the mainstream views and the latest guidelines and listen to the conclusions. Of course, in life, you still need to learn more about nutrition and choose a diet that suits you.