Research suggests that carbs have their own unique taste, and that people who are more sensitive to it may be more likely to gain weight.
There are four established tastes — salty, sour, bitter, and sweet — to which a fifth taste, umami, was officially added not so long ago.
Nevertheless, there are still controversies related to the actual number of tastes that we can perceive, especially since different cultures appear to have different understandings of the taste spectrum.
A new study from Deakin University's Centre of Advanced Sensory Science in Victoria, Australia, now suggests that there is a separate taste for carbohydrate-rich foods. Sensitivity to this taste, the researchers add, may explain why some people are more at risk of gaining excess weight.
"It is typically sugar, with its hedonically pleasing sweet taste, that is the most sought after carbohydrate. But our research has shown that there is a perceivable taste quality elicited by other carbohydrates independent of sweet taste."
Lead author Prof. Russell Keast
The study's findings were published last week in The Journal of Nutrition.
Sensitivity to carbs tied to 'larger waist'
The study focused on two common types of carbohydrates: maltodextrin and oligofructose. You'll find these in some of the most widely available starchy foods, such as pasta, bread, and rice.
These are known as "complex carbohydrates," and, as the team note, they can be sensed in the mouth independently of simple carbohydrates such as sugar.
For the purpose of their study, the researchers worked with 34 adult participants — 16 men and 18 women — to test whether or not individuals who could sense the carbohydrate taste most easily were also more likely to crave starchy foods.
"Those who were most sensitive to the carbohydrate taste ate more of these [carb-rich] foods and had a larger waist," notes Dr. Julia Low — who conducted the initial experiments — about the findings.
The focus on weight and waist size was herein used as an indicator of increased risk of conditions such as overweight and obesity.
"We specifically looked at waist measurements," explains Dr. Low, "as they are a good measure of the risk of dietary related diseases."
One of the reasons for their interest in the link between specific taste sensitivity and food intake is that they need to gain a better understanding of driving factors behind excess weight in order to be able to efficiently tackle what some have recently called an obesity "pandemic."
"Increased energy intake, in particular greater intakes of energy-dense foods, is thought to be one of the major contributors to the global rise of overweight and obesity, and carbohydrates represent a major source of energy in our diet," says Dr. Keast.
Carbohydrate: The seventh taste?
A study conducted by Prof. Keast and another colleague 2 years ago similarly suggested that fatty acids also have a specific taste, to which some people are more sensitive than others.
In that article, Prof. Keast and his co-author proposed that fat might be regarded as the sixth primary taste. This would make carbohydrate the seventh taste in line.
But unlike in his recent study — wherein people sensitive to the taste of complex carbs were also more likely to consume them — "in the fat taste studies [...] the people who were more sensitive to fat consumed less fatty foods, but it's the other way around for carbohydrates," notes Prof. Keast.
"What that could mean," he continues, "is that individuals who are more sensitive to the 'taste' of carbohydrate also have some form of subconscious accelerator that increases carbohydrate or starchy food consumption."
That being said, this possibility is subject to further research for the time being.