Sweeteners are facing some bad press at the moment. But is it all justified? Our nutrition team dives into the studies and what's being said.

Over the past couple of years, there has been frequent media coverage of non-sugar sweeteners, commonly known as artificial, low-calorie, or non-nutritive sweeteners (NSS).

These are sweeteners with little to no calories that can be made artificially or derived from natural sources. NSS are used as an alternative to the sugars commonly found in various manufactured foods and beverages, such as fizzy drinks and yogurts.

Common examples include aspartame, saccharin, sucralose and stevia. Headlines on the topic often focus on the negative side of using these sweeteners. Here’s our nutrition team to break down a couple of the trending topics.

Sweeteners and the WHO

In May of this year, this headline kept popping up in news articles:

‘WHO advises not to use non-sugar sweeteners for weight control or reducing the risk of non-communicable diseases in newly released guideline’

The news centred on a systematic review, which found a lack of evidence that such sweeteners benefit weight loss in the long term and highlighted the possibility of negative effects on health including an increased risk of type 2 diabetes and cardiovascular diseases in adults.

However, the evidence assessed has been evaluated as low certainty by the WHO, and the recommendation is considered ‘conditional’. There is a lack of clarity regarding the trade-off between risks and benefits associated with non-sugar sweeteners.

What do the studies say?

The guideline warns against using NSS for long term weight control. However, evidence from short- term randomised control studies found that higher consumption of NSS in adults was associated with lower body weight and BMI.

Are long term observational studies reliable?

It’s important to understand that these types of studies encounter significant challenges with confounding variables. These are factors that may influence the observed results, such as the overall dietary habits of individuals, so it does not necessarily show cause and effect.

Conclusion

Does this mean that non-sugar sweeteners are no longer safe? No, the WHO recommendation is unrelated to safety.

It’s important to keep on top of the research, yet this appears to be another headline causing unnecessary alarm. It wasn’t too long ago that WHO advised that sugar used in food and beverages can be partly reduced by utilising NSS.

Sweeteners and gut health

Another topic that’s been widely discussed when it comes to sweeteners is their impact on gut health. Here’s some headlines:

’Sweeteners and gut health: No calories does not mean no health effects’

‘Bittersweet: artificial sweeteners and the gut microbiome’

The trend is raising concern that common NSS, such as sucralose or saccharin, have the potential to negatively affect our gut microbiota composition. The term "gut microbiota" refers to the entire community of bacteria and other microbes that inhabit your digestive tract.

However, current research on the impact of artificial sweeteners on the gut microbiome is inconclusive, with mixed findings across studies, and limited human evidence. Currently, no one has fully unraveled the details.

How has the research been conducted?

Most of the research into artificial sweeteners and gut bacteria has focused on laboratory and animal studies. It’s therefore hard to draw conclusions as these don’t reliably predict human outcomes.

Is there evidence in humans that opposes this idea?

Yes, research conducted in 2020 showed that there was no change in gut microbiota composition or diversity following daily consumption of pure sucralose or aspartame for 2 weeks.

What has the latest research said?

A more recent study published in 2022, carried out on 120 humans, concluded that certain NSS have a significant effect on microbiome composition, and these effects are person- specific. This highlights the complexity of the area and the need for further research.

Conclusion

At this point, there’s no definitive conclusion. The main concerns revolve around the fact that key evidence is conducted in animals and the amounts of NSS used far exceed typical human consumption levels. The latest evidence suggests potential effects, but more research is needed to fully understand the relationship as numerous gaps remain.

A few points to remember

The sweeteners we consume are deemed safe by agencies such as the EFSA or FDA.

The negative press about sweeteners, like sucralose, often seems to stem from their artificial nature. It’s important to note that ‘artificial’ doesn’t always mean bad in the same way as ‘natural’ doesn’t always mean good.

Don’t just accept news headlines. Scutinise the evidence. People often accept a study’s findings as gospel and fail to consider its limitations and conflicting factors. Reducing free sugars in diets can be complex, so non-sugar sweeteners appear to be a useful alternative in reducing overall intake.

TL;DR

Non-nutritive sweeteners are gaining popularity as we look to reduce our general sugar intake. Frequently, attention-grabbing news stories around their health credentials. It’s important to dig deeper than the headline, and look into the research supporting the claim, much of which remains inconclusive. Clearly, more research is needed to address the numerous unanswered questions in this current debate.