A Study on the Relationship between Type 2 Diabetes and Taste Function in Patients with Good Glycemic Control

CITATION & LINK: Nutrients, 2020; 12(4), 1112

AUTHORS: Sofia Pugnaloni, Sonila Alia, Margherita Mancini, Vito Santoro, Alice Di Paolo, Rosa Anna Rabini, Rosemaria Fiorini, Jacopo Sabbatinelli, Mara Fabri, Laura Mazzanti, and Arianna Vignini

REVIEWER: Robyn Flipse, MS, MA, RDN

OBJECTIVE:

• To investigate a possible link between diabetes and individual taste function
• The present study was designed to determine taste function in 32 subjects with Type 2 Diabetes (T2DM) with good metabolic control and no complications, and to evaluate the possible influence of age, gender, disease duration, and severity compared to 32 matched controls without T2DM. 

BACKGROUND:

• Taste perception and food preferences have a significant impact on dietary patterns and the likelihood of identifying and consuming foods containing key nutrients. An impairment in taste perception could influence choices towards less healthy foods or unbalanced diets which could negatively impact health. 
• If individuals with T2DM have impaired taste perception for sweet foods, it could lead them to overconsume these foods to obtain the same taste sensation as people with normal sweet taste perception.

METHODS:

• A taste test was performed using cotton pads soaked with four different concentrations of sodium chloride, citric acid, sucrose, and quinine hydrochloride, plus pure rapeseed oil and water to represent fat or a neutral taste. A total of 18 samples were applied alternately to the left and right side of the back third of the protruded tongue in a randomized order for the four concentrations of each solution and the oil and water.
• Subjects had to identify the taste by choosing from a list that included eight descriptions: sweet, salty, bitter, sour, water, fat, nothing, I don’t know.

FINDINGS:

• There were significant differences between the two groups in the ability to recognize each stimuli except fat.
• Subjects with T2DM had lower overall taste discrimination and an age-related decline in taste function.
• The reduction in taste function associated with T2DM was not related to gender, disease duration, and glycemic control.  
• Taste function was equivalent on the left and right sides of the tongue.

CONCLUSIONS:

• It can be hypothesized that the decrease in sweet taste function in T2DM patients can lead to a deterioration of glycemic control and increased risk of complications. This information can be used in dietary counseling for people with T2DM to provide better options to satisfy the desire for sweet taste without increasing the consumption of simple sugars.

POINTS TO CONSIDER:

• People with T2DM having difficulty maintaining good glycemic control may be less able to perceive sweet taste and overconsume foods and drinks containing added sugars in an attempt to reach a desired level of sweetness.
• Foods and drinks sweetened with no- and low-calorie sweeteners offer people with T2DM a way to experience the sweet taste they desire without interfering with glycemic control.