Natural Sweeteners vs Artificial Sweeteners

Since sugar alternatives hit the market there has been debate about whether they are better for you or not. If you walk down the sugar aisle of a supermarket, you may find it a little overwhelming to choose between stevia, monk fruit, low calorie or no calorie sweeteners, rice malt and fruit syrups and the many other options available. 

Some people may opt for sweeteners because they are aiming to reduce their sugar intake. But how can we determine which may be the better option? Or should sweeteners be avoided?

What are sweeteners?

Sweeteners can be artificial or natural alternatives to regular sugar that provide no calories/kilojoules or very low-calories/kilojoules. 

They can be found in many different food and beverage products and must be labeled on the product. Before making a decision, be sure to read food and beverage product labels carefully as sweeteners can be labeled as the name (e.g. “sweetener (aspartame)”) or number (e.g. “sweetener (951)”). 

Labeling of sweeteners is important particularly for people with the rare genetic disorder called Phenylketonuria (PKU). People with PKU are unable to break down phenylalanine, a product of an artificial sweetener Aspartame. People with PKU need to limit their intake of foods containing phenylalanine.

Different types of sweeteners

In Australia, sweeteners are classed as food additives and can be classified into 3 categories:

1. Natural Intense Sweeteners: these are typically derived from plants, are sweeter than regular sugar but contain no carbohydrates or energy. Natural sweeteners include monk fruit (extracted from the fruits of Siraitia grosvenorii), stevia and stevia glycosides (extracted from the leaves of the Stevia rebaudiana plant native to South America). Often natural sweeteners found in supermarkets are combined with nutritive sweeteners like erythritol.
2. Artificial Non-Nutritive Sweeteners: these are artificially created and are energy (calorie and kilojoule) free. Artificial non-nutritive sweeteners are far sweeter than regular sugar and include Acesulphame K, Alitame, Aspartame, Cyclamate, Neotame, ​Saccharin, and Sucralose. 
3. Nutritive Sweeteners: these are typically sugar alcohols derived from different types of carbohydrates, they have less energy than sugar, are typically very low calorie but are not completely calorie/kilojoule free. Nutritive sweeteners include isomalt, erythritol, lactilol, mannitol, maltitol, xylitol, sorbitol, maltodextrin, polydextrose and thaumatin.

Are artificial sweeteners bad for you?

This depends, currently all non-sugar sweeteners (NSS) including artificial sweeteners undergo assessment by authoritative bodies such as the Food Standards Australia and New Zealand (FSANZ) and the Joint Food and Agriculture Organisation / World Health Organisation Expert Committee on Food Additives (JECFA) to establish safe, acceptable levels of daily intake. 

In Australia, the acceptable daily intake (ADI) of sweeteners ranges from 0 to 40mg/kg body weight/day, however these are mostly based on animal studies and population surveys that assess the likely daily intake. Thaumatin and monk fruit sweetener currently have no ADI set as they have been found to have a good safety profile.

The World Health Organisation (WHO) released an updated conditional guideline in 2023 recommending against the use of non-sugar sweeteners (NSS) to control body weight. The recommendation includes all artificial and natural sweeteners, but doesn’t apply to individuals with pre-existing diabetes. In addition, a study on healthy males found that consuming zero-calorie artificial sweeteners or natural sweeteners did not lead to lower total daily energy intake to support weight management.

Are they safe?

There is mixed evidence on the safety of, or any potential side effects of sweeteners. When we consider whether sweeteners are “safe” it’s important to take into consideration which sweetener you are choosing, how much and how often you are consuming it, whether an adult or child is consuming the sweetener, and how strong is the evidence on its safety.

There is evidence to suggest the sweetener saccharin may cross the placenta and can be transferred through breast milk. There is also evidence to suggest artificial sweeteners may reduce egg and sperm quality. Therefore, it is important to consult your healthcare professional if you are pregnant or breastfeeding about your dietary habits.

Preliminary observations on sweeteners’ impact on gut health show that saccharin and sucralose may shift the population of good bacteria in the gut. Further studies are needed to understand the effects that sweeteners may have on gut health.

If you are consuming sweeteners, particularly the nutritive sweeteners (sugar alcohols), be aware that some of these may cause laxative effects in some people.

Is there a best substitute?

The use of sweeteners may be helpful for some to reduce added sugar intake and in turn reduce potential risk factors associated with excess sugar consumption. 

For some it may be a short-term step towards a better diet or a small step towards reducing sugar intake for blood sugar control for people with type 2 diabetes, according to Diabetes Australia. However, the evidence of whether replacing sugar with sweeteners is a better alternative for reducing the risk of chronic diseases such as type 2 diabetes is inconclusive, and consumption of sweeteners may still be associated with increased risks of chronic diseases.

An important consideration with the use of sweeteners, is that artificial, natural and nutritive sweeteners are often used in discretionary foods and beverages, which should be consumed in moderation. By focusing on increasing your consumption of minimally processed wholefoods and consuming a wide variety of all core food groups, you naturally reduce the consumption of all sweetened foods.

The takeaway

Overall there’s no real benefit to consuming added sugars of any type including sweeteners. 

Sweeteners may be a helpful short-term step for some individuals to reduce sugar intake and make a small step towards a better diet. If you choose to use sweeteners in moderation, it’s important to remember that your diet should predominantly be based on minimally processed wholefoods such as vegetables, fruit, lean proteins, wholegrains, and dairy, and these foods typically contain none to minimally added sweeteners or sugars. 

If you need more specific guidance, it’s a good idea to speak with your healthcare professional.

Related reads:

• How to read nutrition labels
• Are you ultra-sure you know what ultra-processed food is? 
• Is sugar really that bad for us?

Reviewed by Healthylife health experts July 2023.