WHO says we shouldn’t worry about artificial sweeteners for weight loss or health. Is sugar better?

This week, the World Health Organization (WHO) advised that non-sugar sweeteners should not be used as a means of gaining weight control or reducing the risk of noncommunicable diseases such as diabetes and heart disease.

Artificial sweeteners are natural compounds or synthesized compounds that taste sweet like sugar and are up to 400 times sweeter by weight but provide little or no energy. By way of comparison, sugar has 17kj (or four calories) per gram, so one teaspoon of sugar would have 85 kilojoules.

Different types of artificial sweeteners are used in Australia. Some are synthetic, others are extracted from foods such as monk fruit and the stevia plant.

So what do the new WHO guidelines mean for people who have switched to artificial sweeteners for health reasons? Should they go back to sugar?

Read more: Food and drink are getting sweeter. While it’s not all sugar, it’s bad for our health

Promoted for weight loss

As a practicing clinical dietitian in the 1990s, I remember when artificial sweeteners started appearing in processed foods. They have been promoted as a way to replace sugar in foods which can lead to weight loss.

A can of sugary drink contains on average about 500 kilojoules. Theoretically, replacing one can of sugary soda daily with one can of artificially sweetened soda would reduce your weight by about 1 kg per month.

But research over the past few decades shows that this doesn’t hold up.

What is the new board based on?

WHO based its recommendation on a systematic review it conducted. Its goal was to provide evidence-based guidance on the use of artificial sweeteners in weight management and for disease prevention.

Weight management is important, as obesity increases the risk of diseases such as diabetes and some types of cancer, which are the leading cause of death globally.

The WHO systematic review included data from different types of studies, which give us different information:

• 50 were randomized controlled trials (when scientists step in and make changes in this case to diet while keeping everything else constant, to see the impact of that change)

• 97 were prospective cohort studies (when scientists look at a risk factor in a large group of people over a period of time to see how it affects an outcome without taking action or making changes)

• 47 were case-control studies (another type of observational study that follows and compares two otherwise matched groups of people, aside from the risk factor of interest).

Randomized controlled trials provide us with causal data, allowing us to state that the intervention led to the change we saw.

The prospective cohort and case control only provide us with associations or links. We can’t prove that risk factors led to a change in outcomes in this case, weight because other risk factors that the scientists didn’t consider could be responsible. But they give very good clues about what might be happening, particularly if we can’t go to trial because it’s unethical or dangerous to give or withhold specific treatments.

The WHO systematic review looked at body fat, noncommunicable diseases and death.

With regards to body fat, randomized controlled trials showed that those who consumed the most artificial sweeteners weighed slightly less on average 0.71 kg compared to those who consumed the least or no artificial sweeteners.

But the cohort studies found that a higher intake of artificial sweeteners was associated with a higher BMI or body mass index (0.14 kg/m2) and a 76% increase in the likelihood of having obesity .

Prospective cohort studies showed that for increased intakes of artificially sweetened beverages there was a 23% increased risk of type 2 diabetes. If artificial sweeteners were consumed as a table food (which the consumer added to foods and beverages) there was a 34% increase in the risk of diabetes.

In people with diabetes, artificial sweeteners did not improve or worsen any clinical markers used to monitor their diabetes such as fasting blood sugar or insulin levels.

Higher intakes of artificial sweeteners have been associated with an increased risk of type 2 diabetes, cardiovascular disease, and death in long-term prospective observational studies that followed participants for an average of 13 years.

But artificial sweeteners weren’t associated with differences in overall rates of cancer or premature cancer death.

Overall, while randomized controlled trials suggested slightly greater weight loss in people who used artificial sweeteners, observational studies found this group tended to have an increased risk of obesity and worse health outcomes.

Does the review have any flaws?

The WHO advice has led to some criticism because randomized controlled trials have shown some weight-loss benefits of using artificial sweeteners, albeit small ones.

However, WHO clearly states that its recommendations are based on multiple research designs, not just randomized controlled trials.

In addition, WHO assessed the quality of the studies in the review with low or very low certainty.

Read more: Sweeteners may be linked to increased risk of cancer new research

Not sure?

This advice doesn’t suggest that artificial sweeteners are unsafe or should be banned. The WHO scientific review did not address chemical or safety issues.

So is it better to have sugar instead?

The answer is no.

In 2015, WHO released guidelines on the intake of added sugars to reduce the risk of overweight and obesity. Added sugars are found in processed and ultra-processed foods and beverages such as sodas, fruit drinks, sports drinks, chocolate and candy, flavored yogurts, and granola bars.

He recommended that people consume no more than 10 percent of their total energy intake, which is about 50 grams (ten teaspoons) of sugar per day for an average adult who needs 8,700 kilojoules per day.

The WHO recommendation is in line with Australian dietary guidelines, which recommend no more than three servings of discretionary foods a day, if you need extra energy. However it is better to get extra energy from the main food groups (grains, vegetables, fruits, dairy and protein group) rather than discretionary foods.

Read more: 8 Everyday Foods You May Not Realize Are Ultra Processed & How to Spot Them

So what do I drink now?

So if artificial and sugar in drinks are not recommended for weight loss, what can you drink?

Some options include water, no-sugar-added kombucha, tea, or coffee. Soda and mineral water flavored with a small amount of your favorite fruit juice are good substitutes.

Milk is also a good option, particularly if you don’t currently meet your calcium needs.