No Need to Resist Sweets? What Research on Sweeteners Has Revealed, Remaining Questions

Standing in front of the refrigerated shelves at a convenience store, I compare regular carbonated drinks with "zero" bottles. I want to reduce sugar intake, but I've heard artificial sweeteners can also be harmful. So, which should I choose?

News about sweeteners has repeatedly fueled such dilemmas. On some days, they are introduced as allies in weight loss, while on others, their adverse effects on appetite and metabolism become the topic of discussion.

On September 22, 2026, a research review introduced by Germany's HNA prompted a reconsideration of the blanket distrust towards sweeteners. It reported that using low- or no-calorie sweeteners instead of sugar did not show a pattern of worsening weight management or measured cardiovascular and metabolic risk indicators.

However, it's too early to conclude that the safety of sweeteners is fully resolved. It's necessary to distinguish between the questions this study answered and those it did not.

The study examined the real-life dietary use of sweeteners

The focus was on a narrative review that organized trials from European research projects SWEET, SWITCH, and Sweet Tooth. This integrates existing research findings into a narrative, differing from a meta-analysis that compiles all research on sweeteners into a single numerical value.

In the five trials introduced by HNA, various conditions were examined, from immediate reactions after consuming cookies and beverages to weight management over about a year.

For example, in SWITCH, a weight loss program with 493 participants compared low-calorie sweetened drinks with water. Sweet Tooth examined how changes in the overall sweetness of meals affected preferences and weight among 180 participants.

These are not studies that merely compare people who drink sweeteners with those who don't. They use randomized controlled trials to investigate differences when dietary or beverage conditions are altered.

The authors of the review also noted the need to pay attention to participant characteristics, intervention conditions, and differences in measurement items. Some assessments of appetite and test values were secondary or exploratory. Even if results are similar, not all studies examined the same questions with the same precision.

"Drinking leads to weight loss" and "substitution is beneficial" are different

In SWEET's weight maintenance study, the use of sweeteners was compared in a diet that maintained reduced weight after initial weight loss. The group incorporating sweeteners showed certain advantages in maintaining the reduced weight.

It's important to note that this was not a trial where sweeteners were simply added to a regular diet. It was a result of using them as part of a sugar-reducing diet.

Replacing sugar-sweetened beverages with low-calorie ones could potentially reduce energy intake. However, if choosing "zero" leads to consuming more snacks, the meaning of substitution changes.

According to the original article, in SWITCH, the group with sweetened drinks lost more weight than the water group. However, this was within a specific weight loss program. It cannot be generalized that "anyone will lose weight by switching from water to zero drinks."

Graham Finlayson from the University of Leeds explained in the original article that retaining sweetness might maintain meal satisfaction, making it easier to continue weight loss behaviors. While this is a strong hypothesis, it doesn't confirm the mechanism.

Why conclusions differ from "studies showing increased appetite"

Concerns about sweeteners also have a research background.

A randomized crossover trial published in 2025 examined brain responses and hunger after consuming sucralose-sweetened drinks. Compared to sugar-sweetened drinks, differences in hunger and other factors were reported.

However, feeling hungry immediately after drinking and gaining weight months later are not the same results. Brain imaging, subjective hunger, actual food intake, and long-term weight changes are separate evaluation items.

The comparison counterpart is also important. Sugar has energy, while water has neither sweetness nor energy. "Compared to sugar" and "compared to water" address different questions.

When reading research results, it's important to check the sweetener's name, comparison target, and observation period. Listing only the "good" or "bad" in headlines can make separate experiments seem contradictory.

Association with disease doesn't equate to causation

Long-term observational studies of daily life sometimes report associations where people who consume a lot of sweetened drinks have higher rates of obesity, diabetes, and cardiovascular diseases.

However, it's possible that people who were already concerned about their weight or blood sugar switched from sugar-sweetened drinks to diet drinks. In this case, health issues might influence beverage choices.

Nevertheless, observational studies remain important for examining diseases that develop over long periods or relatively rare effects.

On the other hand, randomized trials have limitations in duration and participant numbers. Not confirming worsening blood pressure or blood sugar within about a year doesn't mean the risk of heart attacks or strokes over decades is negated.

The current results are a piece of reassurance, not the final answer to all concerns.

How to interpret WHO's recommendations

In 2023, WHO issued a conditional recommendation against using non-sugar sweeteners for weight management or reducing the risk of non-communicable diseases.

The term "conditional" here is important. WHO itself acknowledges that the observed association with diseases might be influenced by participants' original characteristics and complex usage patterns.

Also, this recommendation does not re-evaluate the toxicity of individual sweeteners or set new safe intake levels. "Recommended as a method for long-term health improvement" and "safe to consume in certain amounts" are separate judgments.

People with existing diabetes are excluded from the recommendation's scope, and sugar alcohols are also excluded. Therefore, the same conclusion cannot be applied to all people and all sugar substitutes.

The release of this review alone does not provide grounds to interpret it as "WHO admitted a mistake" or "the recommendation was withdrawn."

Don't treat sweeteners as a single component

The terms "artificial sweeteners" and "sugar substitutes" are convenient, but they include substances with different properties.

The original article also touched on cardiovascular risk studies related to erythritol and xylitol, explaining that the SWEET and SWITCH trials did not separately verify these substances.

Thus, the current results cannot be used to directly dismiss concerns about specific sugar alcohols. Conversely, discussing concerns about one substance as if they apply to all sweeteners is not appropriate.

It's necessary to consider not just the impression of "natural or artificial," but which components are consumed, in what amounts, and in what types of foods.

On social media, "relief" and "still anxious" intersect

The social media reaction to this HNA article itself was not sufficiently gathered within the confirmed range. Here, we introduce reactions posted on the public forum Reddit regarding related research on sweeteners. The following is a summary of the post's intent and does not represent a survey of overall public opinion.

In a thread about the sucralose study in March 2025, there were posts about how sugar-free soft drinks helped with weight loss and experiences of maintaining weight through diet management despite long-term use. On the other hand, there were voices wanting to verify the study's funders.

In a thread about another related study in July 2026, there were repeated requests to know results comparing not only with water but also with sugar. Some posts emphasized the possibility of returning to sugar-sweetened drinks instead of necessarily switching to water when avoiding sweeteners.

Conversely, there were cautious opinions that even if there are advantages over sugar, it doesn't mean they can be consumed without limits.

Such exchanges reveal lifestyle issues outside scientific papers. "What is the ideal choice?" and "What improvements can I continue?" do not always align.

Of course, weight loss experiences on social media do not prove the effects of sweeteners. Diet, exercise, medication, and other factors may change simultaneously. It's also impossible to determine causes from posts alone regarding negative experiences.

Read research funding sources along with results

The original article notes that related research funding includes not only EU research funds but also public-private partnership funds involving the American Beverage Association and private companies. The publication of the review was supported by a related committee of the IAFNS, a food and nutrition research organization.

The presence of corporate or industry group funding does not automatically invalidate the results. However, it is important information for consumers to judge reliability.

What is needed is not to adopt or reject conclusions based solely on convenience but to check research plans, handling of dropouts, evaluation items, and disclosure of conflicts of interest, and to see if results are replicated in independent studies.

Things to consider in front of the refrigerated shelf

The current study suggests that treating sweeteners uniformly as villains could lead to losing options for reducing sugar.

At the same time, the "zero" label does not guarantee the overall healthiness of the food. The purpose of using sweeteners—whether to reduce originally high sugar or to justify adding sweets—changes the meaning.

For those satisfied with water or unsweetened tea, there is no basis for newly incorporating sweetened drinks for weight management. On the other hand, for those who find it difficult to reduce sugar-sweetened drinks, substitution can be a feasible strategy.

The key is not to entrust all health aspects to a single component. News about sweeteners is more useful as material for considering what changes to make in one's diet rather than as a scorecard for determining the goodness or badness of beverages.

Source URL

1. HNA (September 22, 2026)
   Reference to the introduction of five trials, researchers' explanations, distinction from sugar alcohols, and research funding. The text was confirmed with user-provided attachments.
   https://www.hna.de/leben/gesundheit/zuckerersatzstoffe-sind-moeglicherweise-nicht-so-schlecht-fuer-sie-wie-viele-denken-zr-94504436.html

2. Cad et al. 'Nutrients' (2026) / Maastricht University paper information
   Narrative review of SWEET, SWITCH, and Sweet Tooth. Confirm the nature of the research, conclusions, and interpretative limitations.
   https://cris.maastrichtuniversity.nl/en/publications/effects-of-non-nutritive-sweeteners-and-sweet-taste-exposure-on-w/
   https://doi.org/10.3390/nu18111647

3. SWEET study 'Nature Metabolism' (2025)
   Trial examining weight maintenance after weight loss when incorporating sweeteners in a sugar-reducing diet.
   https://doi.org/10.1038/s42255-025-01381-z

4. Trial on sucralose and appetite regulation 'Nature Metabolism' (2025)
   Study examining acute responses to sucralose, sugar, and water in 75 participants.
   https://www.nature.com/articles/s42255-025-01227-8

5. WHO (May 15, 2023)
   Conditional recommendation on the use of non-sugar sweeteners for weight management and explanation of target participants and substances.
   https://www.who.int/news/item/15-05-2023-who-advises-not-to-use-non-sugar-sweeteners-for-weight-control-in-newly-released-guideline

6. WHO "Use of non-sugar sweeteners: WHO guideline"
   Confirmation that the above recommendation does not re-evaluate the toxicity or intake limits of individual sweeteners.
   https://www.who.int/publications/i/item/9789240073616

7. Reddit: r/science (March 2025 related research thread)
   Reactions to research on sweeteners and appetite. Weight loss and management experiences and interest in research funding were noted. Referenced as opinions on social media, not medical evidence.
   https://www.reddit.com/r/science/comments/1jkt3wk/caloriefree_sweeteners_can_disrupt_the_brains/

8. Reddit: r/science (July 2026 related research thread)
   Discussion on whether the comparison was with water or sugar, emphasis on substitution, and cautious views on intake amounts were noted. Not a direct reaction to the current HNA article.
   https://www.reddit.com/r/science/comments/1ulffj3/evidence_that_sugar_substitutes_disrupt_gut/