Many of us are on the lookout for simple swaps and lifestyle changes that can boost our health. One popular trend is using artificial sweeteners in place of added sugar, to reduce the risk of various related health risks.

However, artificial sweeteners remain a hot topic of debate, as research into their effects on health is mixed and ongoing. On the one hand, artificial sweeteners are recommended as a useful tool for weight loss, while other studies suggest they may do more harm than good.

Here, we’ll take a look at what the research says about the link between artificial sweeteners and health.

What are artificial sweeteners?

What are artificial sweeteners?

Artificial sweeteners, also known as non-nutritive sweeteners, are chemicals used to sweeten foods and drinks. They taste similar to table sugar. However, because sweeteners are up to several times sweeter than sugar, the amount needed is so small that they provide virtually no calories.

So, how do sweeteners work?

Our tongues are covered in many taste buds, each of which contains several taste receptors designed to detect different flavours. When a molecule fits perfectly into a receptor, it sends a signal to your brain that allows you to identify the taste. For example, sugar molecules fit into your taste receptor for sweetness – allowing your brain to identify the sweet taste.

Artificial sweetener molecules are similar enough to sugar molecules to be picked up by sweetness receptors but generally too different for the body to break them down. This is what allows them to provide a sweet taste without the extra calories.

There are a small number of artificial sweeteners with a structure the body can break down into calories. But, even in these cases, they provide little to no calories because only tiny amounts are needed to make foods taste sweet.

Some common examples of artificial sweeteners approved for use in the UK include acesulfame L, aspartame, saccharin, sucralose, and sorbitol. For a full list of all food additives, including sweeteners, approved for use in Great Britain, head over to the Food Standards Agency website.

Artificial sweeteners differ from nutritive sweeteners, such as sugar alcohols like sorbitol, which add carbohydrates to food and calories to your diet but contain few vitamins or minerals. You can read more about the differences between nutritive and non-nutritive sweeteners on the Diabetes UK website.

Are artificial sweeteners safe?

According to the NHS, all artificial sweeteners in Great Britain undergo rigorous safety checks before being approved for use in food and drink. The law determines how much sweetener can be used and in which products. As a result, all approved sweeteners are considered a safe and acceptable alternative to sugar.

That said, they may not be suitable for everyone. For example, experts advise that people with phenylketonuria (PKU), a rare inherited condition, should avoid using the sweetener aspartame. Aspartame contains phenylalanine, which people with PKU aren’t able to metabolise. If a product contains aspartame, the ingredients list will include aspartame or its E number E951.

You can read more about the safety of artificial sweeteners on the NHS website.

Artificial sweeteners and health – what does the research say?

Artificial sweeteners and health – what does the research say

Research into the effects of artificial sweeteners on health remains mixed – with various studies suggesting several potential pros and cons.

We’ll explore what the research says below.

Artificial sweeteners, appetite, and weight management

Research into the effects of artificial sweeteners on appetite and weight management is conflicting.

On the one hand, some studies suggest that artificial sweeteners may increase appetite and lead to weight gain. One theory for this is that artificial sweeteners are unable to activate the food reward pathways that leave you satisfied after eating.

There’s also evidence that because sweeteners taste sweet but lack calories, they may confuse the brain into still feeling hungry. Some have even suggested that artificial sweeteners may cause sugar cravings.

In line with these findings, some research has noted a link between a high intake of artificially sweetened drinks and obesity. For example, in this study, people who drank more than 21 artificially sweetened diet drinks per week were found to be twice as likely to become overweight or obese than people who didn’t drink artificially sweetened drinks. There’s also evidence that artificial sweeteners may be addictive; in this study of rats, most chose the sweetener saccharine over cocaine.

However, other research suggests that artificial sweeteners may be a useful tool for weight loss – mainly when used as a replacement for added sugar. This study noted their potential ability to reduce appetite and control cravings – with participants reporting less hunger and consuming fewer calories after replacing sugary foods and drinks with artificially sweetened alternatives.

As a result, research has linked artificial sweeteners with lower body weight, fat mass, and waist circumference. The NHS supports these findings, concluding that artificially sweetened food and drink can be useful for reducing energy intake and preventing weight gain. It also disagrees with any evidence of artificial sweeteners stimulating appetite in humans.

That said, it’s important to note that choosing artificially sweetened alternatives won’t lead to weight loss if you compensate by eating more in other areas. And, since everyone is different, it’s possible that artificial sweeteners may not affect everyone in the same way – so it’s important to find out what works best for you. Research has also found that effects of different artificial sweeteners can vary.

Artificial sweeteners and gut health

The human gut contains up to 1,000 species of bacteria, collectively known as the gut microbiome. Maintaining a balanced gut microbiome is key for gut health and overall wellbeing.

Gut bacteria composition varies from person to person and is largely influenced by what you eat – including artificial sweeteners. And there’s evidence that artificial sweeteners may negatively impact the balance of beneficial bacteria in the gut.

In this study, when mice ate the artificial sweetener, saccharin, the composition of their gut microbiome changed – including a reduction in some beneficial bacteria. Another study also found that saccharin and sucralose intake decreased healthy gut bacteria. In line with these findings, this study revealed that people who consume artificial sweeteners have different gut bacteria profiles than those who don’t.

However, other studies suggest that the effects of artificial sweeteners on gut bacteria may only affect some people, so further research is needed to confirm the connection.

According to the NHS, some nutritive sweeteners, known as polyols (including sorbitol, xylitol, and erythritol) can have a laxative effect if consumed in large amounts. However, if polyols added to a food or drink make up more than 10% of a product, by law, the label must state that overconsumption may cause laxative effects. Polyols are sugar alcohols and can be produced naturally or artificially. They contain carbohydrates and calories, but have fewer calories and less of an effect on blood sugar levels than sugar.

Artificial sweeteners and gut health

Artificial sweeteners and cancer

Cancer Research UK says there’s no convincing evidence that artificial sweeteners cause cancer.

However, other research suggests that this may largely come down to the amount you consume. Some studies have found that overconsumption of artificial sweeteners may have negative consequences.

In this study, for example, consuming diet soda daily was associated with a 36% higher risk of metabolic syndrome. Metabolic syndrome, which refers to a group of five health risk factors, including high blood pressure, cholesterol, and blood sugar, has been linked with a higher risk of four cancer types.

Artificial sweeteners and oral health

Diets high in added sugar are known to increase the risk of tooth decay and cavities – so it’s possible that replacing sugar with artificial sweeteners may benefit oral health.

According to Colgate, unlike regular sugar, artificial sweeteners aren’t considered cariogenic – meaning they don’t contribute to tooth decay. Even more so, some studies have noted that, while artificial sweeteners don’t contribute to tooth decay, they may even work against it.

As researchers at Colgate explain, when you eat or drink something containing sugar, pH levels in your mouth drop due to increased acidity. However, artificial sweeteners seem to have the opposite effect, which may help to maintain balanced pH levels and reduce the number of decay-causing bacteria in your mouth.

That said, it’s worth noting that, while artificially sweetened beverages don’t contain sugar, they do contain other acids which can contribute to enamel breakdown and tooth decay. As Harvard Medical School notes, by trading sugary drinks for artificially sweetened alternatives, you’re simply replacing one nutritionally questionable drink with another. So, while they can be useful for reducing the amount of sugar in your diet, it’s important to moderate your intake.

Artificial sweeteners and diet diversity

While artificial sweeteners can help to improve diet by reducing sugar intake, evidence suggests that overuse may start to affect the way we taste and experience food.

Because they’re far sweeter than table sugar, studies suggest that routine use of artificial sweeteners may cause people to find less intensely sweet foods, such as fruit, less appealing – and even unsweet foods, such as vegetables, unpalatable. Fruit and vegetables are a key source of fibre, vitamins, and minerals, and getting enough in your diet is essential for overall health and protecting against conditions like heart disease and diabetes.

Artificial sweeteners and diabetes

The main use of artificial sweeteners is to reduce added sugar intake, so they may be particularly beneficial for people with diabetes – by offering a sweet taste without causing blood sugar spikes.

For example, various studies have found that artificial sweeteners don’t affect blood sugar or insulin levels.

That said, moderation remains important, as research suggests that overconsumption of artificial sweeteners may actually increase the risk of diabetes. In this study, daily consumption of diet soda was associated with a 67% greater risk of type 2 diabetes compared with nonconsumption.

Final thoughts…

While research into the effects of artificial sweeteners on health remains ongoing, there’s evidence that artificial sweeteners may have potential health benefits – particularly when used as a replacement for added sugar.

However, evidence clearly shows that this all comes down to moderation. Research suggests that overconsumption of artificial sweeteners may lead to negative outcomes – such as gut microbiome imbalances, reduced tolerance of whole foods, and an increased risk of certain health conditions.

For further reading, head over to the diet and nutrition section of our website. Here, you’ll find information on everything from healthy cooking methods to simple diet swaps for a healthier lifestyle.

What’s your opinion on artificial sweeteners? Do you have any other thoughts that you’d like to share? We’d be interested to hear from you in the comments below.