Natural vs Artificial Sweeteners: Which is the better choice?

When it comes to cutting down on sugar, many people turn to alternatives believing they are a healthier or lower-calorie option, but with so many choices, it’s easy to get confused. The debate often centres on so-called ‘natural’ sweeteners such as honey, agave syrup, or coconut sugar versus ‘artificial’ sweeteners like aspartame or sucralose, and even newer options like stevia and xylitol, which blur the lines between natural and synthetic. The word ‘artificial’ often gets a bad rap, while ‘natural’ is taken as shorthand for healthier. But is it really that simple? Natural vs Artificial Sweeteners, lets dig in to it:

What are sweeteners?

Sweeteners are substances used to provide a sweet taste either with or without calories. They generally fall into three broad categories:

Natural sugars

These are often marketed as ‘natural’ and healthier than table sugar. But from a nutritional point of view, they’re still sugar, they raise blood glucose and contribute a similar number of calories.

These include:

• Honey
• Maple syrup
• Molasses
• Golen syrup
• Agave syrup

Non-sugar sweeteners (NSS)

This is the official term used by health organisations such as The World Health Organisation (WHO). It includes artificial sweeteners such as aspartame, sucralose, and acesulfame K which are synthetically produced compounds that are often hundreds of times sweeter than sugar. They are used in small amounts and typically provide little to no calories.

Natural-origin non-sugar sweeteners

These are sometimes grouped with artificial sweeteners but are derived from natural sources:

• Stevia (from the stevia leaf)
• Sugar alcohols (polyols) like xylitol, erythritol, and sorbitol

Although they come from natural sources, they still undergo processing to become sweeteners. They vary in sweetness, calorie content, and how they affect digestion

Are natural sweeteners the better choice?

Natural sweeteners like honey, coconut sugar, and maple syrup are often marketed as healthier because they contain trace nutrients like B vitamins, minerals, or antioxidants. For example, raw honey contains tiny amounts of iron and flavonoids, while coconut sugar is often said to have a lower glycaemic index due to its inulin content.

You do need to put this into perspective as the amounts of these nutrients are so small you would need to eat several tablespoons to see any real benefit, which would cancel out any advantage. And while coconut sugar may have a slightly lower glycaemic index than table sugar, the difference isn’t dramatic. Your body still processes it in a similar way, raising blood sugar and insulin. In excess, all these sugars contribute to weight gain and metabolic risk (your risk of developing conditions like heart disease, type 2 diabetes, and stroke).

What about artificial sweeteners?

Artificial sweeteners are designed to offer the sweet taste without the calories. Sucralose, aspartame and acesulfame K are common examples used in diet drinks, protein powders and sugar-free products. Then you have stevia and polyols, which come from natural sources but are still processed to make them usable.

Pros:

• Weight control: A 2016 meta-analysis found that low-calorie sweeteners helped reduce energy intake and body weight when substituted for sugar¹.
• Blood sugar: Unlike natural sugars, artificial sweeteners do not raise blood glucose levels, making them useful for people with diabetes.
• Dental health: Polyols like xylitol help prevent tooth decay, which is why they are used in sugar-free gum.

Cons:

• Gut health: Some evidence (mostly animal-based) suggests artificial sweeteners like saccharin and sucralose may alter gut bacteria in ways that could negatively affect metabolism². However, human evidence is limited, and the doses in studies often far exceed what most people consume.
• Digestive discomfort: Polyols can cause bloating, gas and diarrhoea in sensitive people or when consumed in large quantities. Erythritol tends to be better tolerated.

How much sugar is too much?

The UK recommendation is to limit ‘free sugars’ to no more than 30g per day (around 6 teaspoons). Free sugars include those added to food, plus naturally occurring sugars in honey, syrups, unsweetened fruit juice and smoothies. This is why fruit juice intake is advised to be limited to no more than 150ml per day even if it’s 100% juice.

Hidden sugars are everywhere in foods such as yoghurt, breakfast cereal, sauces, snack bars, and even products labelled ‘natural’ or ‘healthy’. Common aliases include fruit juice concentrate, brown rice syrup and date syrup, but don’t be fooled. They may sound more wholesome, but they are still sugars and are metabolised in much the same way.

Does sugar have any benefits?

When I work with sportspeople, there are times when ultra-processed foods (UPFs) are one of the most practical ways to get enough rapid-acting carbohydrate into the body before or during an event even if that means eating a handful of Haribo’s or drinking a sugary soft drink. 

Sugar is not necessarily unhealthy all the time and in the case of athletes or anyone training at high intensity, sugar (glucose) is an efficient, fast-acting fuel. It helps replenish glycogen stores, sustain energy, and support both performance and recovery. During endurance events, glucose can delay fatigue and help maintain performance.

So, if your goal is peak performance rather than weight loss, a little sugar at the right time can be useful.

What does the research say about artificial sweeteners and health?

From a safety standpoint, all artificial sweeteners approved for use in the UK have been extensively tested and deemed safe by the European Food Safety Authority (EFSA) and the UK Food Standards Agency. Each has an Acceptable Daily Intake (ADI), which is typically far above what the average person consumes.

For example, to reach the ADI for aspartame, you would need to drink over a dozen cans of diet soft drink a day and even then, studies show no conclusive evidence of harm in humans³.

However, concerns do persist around long-term use and potential subtle effects on appetite regulation or gut health. The evidence around gut microbiota disruption is still developing, with a 2019 review concluding that data is inconsistent and more human studies are needed⁴.

So, which sweetener should you choose?

Ultimately, it depends on your health goals and how your body responds:

Weight loss: Artificial sweeteners or stevia can help reduce calorie intake while still satisfying sweet cravings. But you can also enjoy a little real sugar occasionally. It’s about portion size and overall balance, not total restriction.

Blood sugar control: Artificial sweeteners or sugar alcohols like erythritol have minimal impact on blood glucose levels. If you do include a small amount of sugar, try pairing it with fibre, protein, or healthy fats to help slow down absorption and keep blood sugar more stable.

Better digestion: Small amounts of natural sugars or stevia; avoid polyols if sensitive

Sports performance: Glucose, maltodextrin or even sucrose (table sugar) for quick energy

Reducing cravings: Gradually retrain your palate but keep in mind that sweeteners can keep the ‘sweet tooth’ alive

It’s worth experimenting. Some people find artificial sweeteners increase cravings or don’t satisfy them, while others find them useful tools in reducing sugar intake.

What is the bigger picture?

It’s tempting to search for the ‘best’ sweetener and compare natural vs artificial sweeteners, but the reality is that if the rest of your diet is based on whole, nutrient-dense foods, your choice of sweetener in your tea or breakfast bowl is not going to make or break your health. Where sweeteners become problematic is when they are a crutch for a diet that is already high in ultra processed foods. Whether it’s agave syrup in a health bar or aspartame in a fizzy drink, it’s still best to focus on real, minimally processed foods overall. 

References

1. Rogers, P. J., Hogenkamp, P. S., de Graaf, C., Higgs, S., Lluch, A., Ness, A. R., Penfold, C., Perry, R., Putz, P., Yeomans, M. R., & Mela, D. J. (2016). Does low-energy sweetener consumption affect energy intake and body weight? A systematic review, including meta-analyses, of the evidence from human and animal studies. International journal of obesity (2005), 40(3), 381–394. https://doi.org/10.1038/ijo.2015.177
2. Suez, J., Korem, T., Zeevi, D., Zilberman-Schapira, G., Thaiss, C. A., Maza, O., Israeli, D., Zmora, N., Gilad, S., Weinberger, A., Kuperman, Y., Harmelin, A., Kolodkin-Gal, I., Shapiro, H., Halpern, Z., Segal, E., & Elinav, E. (2014). Artificial sweeteners induce glucose intolerance by altering the gut microbiota. Nature, 514(7521), 181–186. https://doi.org/10.1038/nature13793
3. Magnuson, B. A., Burdock, G. A., Doull, J., Kroes, R. M., Marsh, G. M., Pariza, M. W., Spencer, P. S., Waddell, W. J., Walker, R., & Williams, G. M. (2007). Aspartame: a safety evaluation based on current use levels, regulations, and toxicological and epidemiological studies. Critical reviews in toxicology, 37(8), 629–727. https://doi.org/10.1080/10408440701516184
4. Ruiz-Ojeda, F. J., Plaza-Díaz, J., Sáez-Lara, M. J., & Gil, A. (2019). Effects of Sweeteners on the Gut Microbiota: A Review of Experimental Studies and Clinical Trials. Advances in nutrition (Bethesda, Md.), 10(suppl_1), S31–S48. https://doi.org/10.1093/advances/nmy037