Sweeteners and sugar substitutes for diabetes: Should you consume them?

Diabetes and free sugars 

Type 2 diabetes is a chronic metabolic disease affecting more than 400 million people worldwide. It is characterised by elevated fasting blood glucose levels which can be caused by insufficient insulin production or a resistance to the insulin produced in the pancreas. Over a long period, diabetes can cause damage to the blood vessels, eyes, and heart. Diabetes treatment often rely on a combination of physical activity, dietary guidelines, and medication if necessary.  

As they are directly linked to blood sugar levels, carbohydrates have often been targeted in dietary interventions for the treatment of diabetes. Sugars are naturally occurring carbohydrates found in fruit juices or purees, cane sugar, honey, syrups, molasses, etc. These free sugars can also be added to foods and drinks, such as biscuits, sweets, ready meals, and fizzy drinks. They provide calories to fuel our body and raise blood glucose levels. It is recommended for most adults to limit their free sugar intakes to 30g per day (or about 7 sugar cubes) to help maintain a healthy weight and prevent cardiometabolic diseases, among other benefits. This is particularly important for type 2 diabetes patients who often need to achieve sustainable weight loss to control their condition and need to monitor their blood glucose levels on a daily basis. 

What are sweeteners and sugar substitutes? 

Sometimes, only sweet something will do! That is when sugar substitutes can be helpful, as they can replicate the sweet taste of sugar with little to no impact on calorie intake or blood glucose levels. There are many types of sweeteners available to choose from, such as: 

• Polyols, which are sugar alcohols that contain carbohydrates. They provide fewer calories and have a weaker effect on blood glucose level than regular sugars. They can be recognised on food labels thanks to their “-ol” ending: erythritol, maltitol, mannitol, sorbitol, xylitol, etc.  
• Artificial sweeteners, which provide no calories and have no effect on blood glucose levels. They include aspartame, saccharin, sucralose, acesulfame-K, cyclamate, etc.  
• Sweeteners from the stevia plant, which are also calorie-free and have a great sweetening power (about 200-300 times sweeter than regular sugar).  

Most of them are sweeter than regular sugar and only need to be used in small amounts to achieve the desired effect. However, only a handful are stable when heated and can thus be used for cooking and baking: sucralose, acesulfame-K, and sweeteners from the stevia plant. Aspartame can be used in hot drinks, but may lose some of its sweetness when heated up at high temperatures.  

Sweeteners for diabetes management 

The main benefit of sweeteners is the most obvious one: being able to enjoy sweet foods and drinks without worrying about blood sugar levels or weight gain. For diabetic patients, sugar substitute can thus become a real mood booster that will help them maintain their prescribed dietary habits in the long run.  

For this reason, most dietitians agree that a moderate consumption of sugar substitute can be beneficial for diabetic patients. Nonetheless, they should not replace all sugars from the diet – maintaining a completely sugar-free diet is almost impossible in the long-run, even for diabetic patients! Naturally occurring sugars like those found in fruits and vegetables can easily fit in a diabetes-friendly diet while providing key nutrients to maintain a healthy mind and body: fibre, vitamins, minerals, etc. Speaking with a registered nutrition professional is critical to creating a personalised, balanced diet with or without the help of sugar substitutes. 

Potential side effects of sugar substitutes 

Most people will be able to consume sweeteners without any issues. However, it may be best to avoid or limit sugar substitutes in some circumstances: 

• Some patients with diabetes may experience hypoglycaemia when their blood sugar level becomes too low. In this situation, it is important to consume actual sugar, in a fast-absorbing form like a sugary drink, as most sugar substitutes will not have any effect on blood sugar levels.  
• Some sweeteners may have a laxative effect if consumed in large amounts. This includes polyols, which are often found in sugar-free gums, sweets, and syrups. People with pre-existing gastrointestinal disorders like IBS are particularly at-risk of bloating and diarrhoea due to polyol consumption, but people with an otherwise healthy gut can also experience these uncomfortable symptoms. 
• Polyols also have a small effect on blood sugar levels, although it is difficult to quantify and predict to which extent because not all of the sweetener molecules are absorbed by the body during the digestion process. Therefore, patients with diabetes should speak with their healthcare provider or a registered dietitian to make sure these sweeteners can fit into their diet. 
• People suffering from phenylketonuria (PKU), a rare inheritable metabolic disease, must avoid consuming aspartame. Indeed, after being absorbed in the body, aspartame is converted into the amino acid phenylalanine, which PKU patients cannot metabolise – potentially leading to brain damage if present in too high quantities in the blood stream.  

Are sweeteners safe to consume?  

Before reaching the supermarket shelves, sweeteners must be evaluated and approved for consumption by the Food and Drug Administration (FDA). As part of this process, the FDA defines an Acceptable Daily intake (ADI) level, which is the amount of sweetener a person could consume every day (per kg of body weight) over their whole life, without risk. The safety of sweeteners is also monitored over time with regular re-evaluations to make sure that all the most recent scientific evidence is accounted for.  

Nonetheless, the safety of sweeteners is regularly debated in mainstream media. Indeed, recent observational research has suggested potential links between high consumption of sweeteners and the risk of cardiovascular disease, cancer, and even type 2 diabetes in a large cohort of French adults. In addition, some preclinical research has suggested artificial sweeteners may be linked to disruptions of the gut microbiota, although these findings are inconsistent across studies.  

In 2019, the European Food Safety Authority (EFSA) has started a re-evaluation process of artificial sweeteners to assess the long-term risks and benefits of their consumption in light of the most recent scientific evidence – with conclusions still pending to this day. 

Key messages 

• Sweeteners can help patients with diabetes, and others, to achieve and maintain weight loss and control their blood sugar levels on daily basis.  
• While all sweeteners available on the market have undergone a rigorous evaluation process, emerging scientific research has yet to be considered in the re-evaluation of their long-term safety and benefits.  
• Speaking with a registered dietitian or healthcare provider, along with carefully reading food labels, is the best way for patients with diabetes to make an informed choice on whether they want to consume sugar substitute to help manage their condition. 

Was this article helpful to you?
  
Give it a "Like" and share your thoughts and questions with the community in the comments below! 
 
Take care!