Artificial Sweeteners: Do they really trick the taste buds?


With the shift in people's diets to a "healthier" way of life, food and beverage manufacturers have found it necessary to develop low-calorie or no-calorie products without compromising the actual taste of sugar expected by consumers. While these artificial sweeteners can replace sugar in whole or in part, they are rarely as satisfactory as the full-sugar alternative, both from the taste and satiety points of view.


Does the taste of food change when I use artificial sweeteners?

The answer is yes, and not only in taste but also in color and smell, depending on the artificial sweetener and the food in which it is used. This is because, unlike sucrose, most artificial sweeteners exhibit unpleasant flavors as their concentration increases, changing from pleasant (sweet) to unpleasant (bitter/metallic).


How do taste buds’ receptors work?

Imagine that there are little locks on your taste buds and, when a food molecule fits into place like the key to that lock, the receptor sends a signal to your brain. Consequently, when you taste something sweet like chocolate, those molecules fit into your sweet receptor and send a message to your brain that the chocolate is delicious.


Sugar always adapts to our sweet receptors, but artificial sweeteners are a bit more complicated. Ace-K sweetener, commonly found in diet beverages, can bind both sweet and bitter receptors. This explains why we feel a bitter sensation in our mouth at the end of each sip when we drink a zero-sugar soda.

When artificial sweeteners first became popular, they seemed like the perfect alternative to sugar. However, it turns out that the more studies run on no-calorie sweeteners, the more problems we find that can arise if we consume them on a regular basis. One example is aspartame, which, according to some studies, can lead to increased weight gain over time as well as other side effects - let's look at why.


Artificial Sweetener from a satiety point of view

The human body evaluates the quality of a food by means of sensory information on taste, detecting at least five basic taste qualities: sweet, salty, umami, sour, and bitter. This taste detection starts with the apical membrane of the taste receptor cells. These receptors bind to the taste substances, recognize them, and activate the taste cells, which then transmit sensory information to the nerve cells and the brain.


So, what happens when the brain detects the sweet taste of an artificial sweetener?


These receptors recognize all compounds (natural or artificial) perceived by humans and provide information on the caloric and macronutrient content of the food ingested.


This is where the body's reward system comes into play in regulating eating behavior. Evolutionary survival mechanisms in the brain value calorie-rich foods, so we find sugar satisfying and we are continually seeking it out, but what happens if we eat foods prepared with artificial sweeteners?


If sweet taste is no longer a reliable measure of caloric intake because you regularly consume artificial sweeteners, the brain's reward response to sweet taste is likely to change. For example, a study conducted at San Diego State University found that, while diet beverages are calorie- and sugar-free alternatives, it does not mean they are healthy, much less beneficial. It has been shown that the artificial sweeteners in beverages could lead to increased hunger and overeating.


Other problems associated with sweeteners

Recent studies suggest possible links between non-nutritive sweeteners and changes in appetite and taste preferences in children, which could also affect their weight and health. Another study examines whether these artificial sweeteners cause changes in the gut microbiome, which is composed of "beneficial" bacteria, that could affect blood sugar levels and lead to metabolic syndrome, insulin resistance, and diabetes.

Therefore, the substitution of sugar by artificial sweeteners does not necessarily mean a lower overall caloric intake and, on the contrary, it could induce unbalanced eating behaviors that lead to a high consumption of sweetened and low-calorie products as well as a high consumption of other products with excess calories.