A 27-year-old man in China was hoping to lose weight by giving up carbonated drinks and switching to beverages labelled “zero sugar” or “sugar-free”.
Instead, after more than a year of regularly consuming the drinks, his weight had increased by 2kg and a health screening also found that his blood lipid levels were elevated.
The man, identified by Chinese media only by his surname Sun, had been told during a health check in January last year that he was overweight. He subsequently decided to cut out conventional soft drinks as part of his weight-management efforts.
However, when he underwent another medical examination in April this year, he discovered that his weight had gone up rather than down.
Zero-Sugar Does Not Automatically Mean Healthier
According to Chinese media reports, Sun sought treatment at Nanjing First Hospital, where a doctor from the hospital’s endocrinology and metabolism department assessed his situation.
The doctor explained that beverages marketed as “zero sugar”, “sugar-free” or “no sucrose” can still contain sweeteners. Common ingredients include erythritol, aspartame, sucralose and acesulfame potassium.
However, it is important not to assume that all sweeteners are inherently dangerous. Major food-safety authorities continue to consider approved sweeteners safe when consumed within established limits. For example, the US Food and Drug Administration says aspartame is considered safe for the general population under approved conditions of use.
The bigger issue for people trying to lose weight may be how these products fit into their overall eating habits.
The World Health Organization advises against relying on non-sugar sweeteners as a long-term strategy for weight control. Its review found that they do not provide a clear long-term benefit for reducing body fat, while some observational evidence has linked long-term consumption with higher risks of conditions including type 2 diabetes and cardiovascular disease. The recommendation is conditional, meaning the evidence is not strong enough to establish that sweeteners themselves directly cause these conditions.
Three Potential Problems With Relying On Sugar-Free Drinks
One concern is that people may continue to maintain a strong preference for very sweet flavours. Replacing sugary drinks with intensely sweet alternatives can reduce sugar intake, but it does not necessarily reduce a person’s overall desire for sweet foods.
A second issue is what nutrition researchers sometimes describe as compensation. Someone may feel that choosing a zero-sugar drink has “saved” calories, then consume additional food later. If the extra calories from meals, snacks or desserts outweigh the calories avoided from sugary drinks, weight loss will not occur.
The third issue is that “zero sugar” does not necessarily mean zero calories or that the entire product is nutritionally neutral. Consumers should look beyond the front-of-package marketing and check the nutrition information and ingredient list.
At the same time, claims that artificial sweeteners directly cause insulin resistance or obesity should be treated cautiously. WHO’s evidence review found uncertainty around long-term effects, while its guidance specifically notes that associations from observational studies can be affected by underlying differences between people who consume more or fewer sweeteners.
Water Remains The Simplest Choice
For people trying to lose weight, the most reliable approach remains controlling overall calorie intake while maintaining a balanced diet and regular physical activity.
WHO recommends reducing free sugar intake and says this should not simply be achieved by replacing sugary foods and drinks with non-sugar sweeteners. Instead, people are encouraged to gradually reduce their preference for sweetness and choose unsweetened foods and beverages more often.
For everyday hydration, plain water remains the simplest option. Unsweetened tea and other drinks without added sugar can also be useful alternatives.
Zero-sugar drinks can still be a practical way for someone to reduce their intake of sugar-sweetened beverages, particularly when they are replacing a high-calorie soft drink. But they should not be viewed as a licence to eat more or as a guaranteed weight-loss product.
Ultimately, losing weight depends far more on a person’s overall diet, calorie intake, activity levels and long-term eating habits than on whether a drink carries a “zero sugar” label.