Diet sodas and sugar-free alternatives are hitting the shelves in waves since the revolt against sugar.
Almost every mainstream drink has a sugar free or diet version today, often more than one. Coke No Sugar, Diet Coke, Coke Zero, Pepsi Max, Sprite Zero, Coke Life, Pepsi Light, even milk drinks are spawning low-sugar variants.
And while there is no doubt that liquid sugar calories are a burden on a whole host of growing health problems for the Western world, are the sugar-free alternatives really as healthy as they are made out to be?
What are Artificial Sweeteners?
Artificial sweeteners are synthetic chemicals, or in some cases naturally occurring chemicals designed to replace sugar while still providing that sweet sweet taste.
While you might think artificial sweeteners are limited to drinks, they are often found in a whole range of food and drinks including TV dinners, cakes and even chewing gums.
The main artificial sweeteners used today include:
- Acesulfame Potassium (950)
- Aspartame (951)
- Cyclamate (952)
- Neotame (961)
- Saccharin (954)
- Sucralose (955)
- Stevia (Natural)
Do Artificial Sweeteners Raise Blood Sugar Levels?
Our blood sugar levels rise when we eat carbohydrates. You may have heard of low GI and high GI foods.
GI stands for glycemic index and refers to how fast a carbohydrate is digested and absorbed. The higher the GI (glycemic index), the faster our blood sugar levels rise.
However, unlike glucose, fructose like that found in high fructose corn syrup used in most sugary drinks today doesn’t cause blood sugar levels to rise in the short term.
That isn’t to say that fructose is harmless, it may raise LDL cholesterol, and because it is metabolised by the liver, cause issues such as non-alcoholic fatty liver disease.
So do our “healthy” alternatives have the same effect on blood sugar levels as high GI carbohydrates?
Current research is pointing to no, they don’t directly, however they may affect blood sugar levels indirectly via other means.
A 2014 study¹ determined that when fed artificial sweeteners for 11-weeks, mice had negative changes in their gut bacteria, which lead to an increase in blood sugar levels.
Even if we discount the fact that blood sugar levels saw an increase, a negative change in gut bacteria also puts a strike against sugar-free drinks falling into the healthy camp.
Do Artificial Sweeteners Raise Insulin Levels?
To answer whether artificial sweeteners raise insulin levels, we need to break them out of one large category into individual components.
While not all artificial sweeteners have shown to raise insulin levels, acesulfame potassium, saccharin and sucralose have shown to potentially raise insulin in research studies.
Injecting large amounts of acesulfame potassium into rats² showed massive increases in insulin levels, however, the effects in humans are unknown.
Do Artifical Sweeteners Cause Weight Gain?
While sugar-free drinks are often marketed as zero calories, the body is a complex beast and sometimes weight gain can be a result if an indirect mechanism.
Sugar-free drinks may potentially cause weight gain be contributing to bad dietary habits by those who consume them. A person who consumes large amounts of soft-drink, whether normal or sugar-free may be more likely to practice other nutritional no-nos such as eating excessive fast food and indulging in more sweet tooth desserts.
Some studies actually show that replacing normal drinks with sugar-free variants cause weight loss³. This may be due to the fact that sugar-free soft-drink while being calorie free still creates a sensation of satiety.
Diet Soda and Diabetes
While sugar-free drinks don’t directly raise blood sugar, some artificial sweeteners do cause a rise in insulin levels as discussed earlier on.
This could account for the fact that some studies have shown that artificially sweetened drinks still increase the risk of type 2 diabetes⁴.
However, the risk of developing type 2 diabetes from artificially sweetened drinks was still half that of their full sugar counterparts.
Diet Soda and the Heart
A daily intake of artificially sweetened drink has been shown to raise blood pressure and result in a small increase in risk for stroke⁵.
Again, this study is observational so it’s difficult to determine if this was directly caused by the artificial sweeteners used or other dietary misdemeanours.
While sugar-free soft drink doesn’t cause the same number of problems as full sugar soft drinks, juices and other high-sugar intakes, there are still potential side-effects seen in various studies from sugar-free soft drinks.
So while we can conclude that sugar-free or diet drinks aren’t “as bad” for you as their full sugar counterpart, they definitely don’t fit the criteria for being healthy either.
The other aspect is whether we define healthy as providing nutritional value or some kind of benefit to the body, sugar-free diet drinks definitely don’t fit this definition.
They may provide a healthier alternative to full sugar drinks by omission, but this in itself doesn’t make them healthy as such.
- https://www.ncbi.nlm.nih.gov/pubmed/2887500, https://www.ncbi.nlm.nih.gov/pubmed/2887503
- https://www.ncbi.nlm.nih.gov/pubmed/2349932, https://academic.oup.com/ajcn/article/95/3/555/4578292
- https://www.ncbi.nlm.nih.gov/pubmed/26199070, https://www.ncbi.nlm.nih.gov/pubmed/24932880