While reviewing the Whole30’s It Starts With Food, I came across an interesting tidbit I thought deserved its own post. If you have ever read anything about artificial/low-calorie/nonnutritive sweeteners, it’s likely you’ve come across the following statements [1]:
- Aspartame (Equal) is 200 times sweeter than table sugar
- Stevia (Truvia) is 200-400 times sweeter than table sugar
- Sucralose (Splenda) is 600 times sweeter than table sugar
- Saccharin (Sweet’N Low) is 200-700 times sweeter than table sugar
These statements may lead you to believe that high potency nonnutritive sweeteners (NNS) like the ones listed above are many times sweeter than sugar, causing the reward and pleasure signals in your brain to go haywire. Would you be surprised to hear that in reality sugar actually ranks higher in sweetness than common NNS?
The myth of the exorbitantly sweet NNS stems from a misunderstanding of how sweetness is measured. When testing for sweetness, both potency and intensity are recorded from trial participants. Dr. Walters, Ph.D. gives a good overview of the testing procedures [2,3].
“Sucrose is the standard to which all other sweeteners are compared. Humans can recognize sweetness in about 1% or 2% sucrose solution. Coffee is typically sweetened to about the level of 5% sucrose [and] soft drinks about 10%. At 15%, sucrose is really sweet and starts to feel a little syrupy. Taste panelists are often trained to quantitate sweetness on a 0-15 sweetness scale…using [a range of] 2-15% sucrose solutions as references. Other sweeteners are then tasted at a series of dilutions to determine the concentration that is as sweet as a given sucrose concentration. For example, if a 1% solution of sweetener X is as sweet as a 10% sucrose solution, then sweetener X is said to be 10 times as potent as sucrose.”
So when someone says “aspartame is 200 times sweeter than table sugar” what they are really saying is that it is 200 times more potent than table sugar because you can use a lower dose to obtain the same perception of sweetness. It is not an indication that aspartame delivers a higher-intensity stimulus than sugar; merely that it triggers the taste receptors for sweetness on your tongue at a lower dosage.
Intensity, not potency, is what we really want to look at when comparing natural and NNS. Intensity is the true measure of sweetness perception. While early research has provided rankings of sweeteners most have used small sample sizes [3,4]. However, a study published in the International Journal of Obesity tested 3 nutritive sweeteners (sucrose, maple syrup and agave nectar) and 4 NNS (acesulfame-K (AceK), rebaudioside A (RebA), aspartame and sucralose) using a large cohort of 401 participants [5]. Ranked from most to least sweet, the results were as follows:
- Maple Syrup
- Agave Nectar
- Sucrose (table sugar)
- Aspartame
- Sucralose
- RebA
- AceK
All 3 nutritive sweeteners beat out the 4 tested NNS. A probable cause for why NNS rank lower than sugar may be due to the suppression of the sweet taste by bitter and metallic compounds that become more prominent as the dosage increases.
The researchers concluded the following [5]:
“Non-Nutritive Sweeteners (NNS) are not supernormal stimuli. Although NNS have low psychophysical detection thresholds compared with sugars, it is not valid to use thresholds or the dose over threshold to estimate the perceived intensity of these sweeteners…present data do not support the claim that NNS produce deleterious health effects by overstimulating sweet taste receptors to produce hyper-intense sweet sensations.”
So the next time you hear someone claiming that NNS are frying the pleasure centers of your brain, kindly explain to them the myth of the supernormally stimulating nonnutritive sweetener.
For more info, check out the YouTube videos below.