Study: NCT04633109

Intervention type: PROCEDURE
Intervention: taste bud biopsy
Description: Taste buds will be surgically removed a) during a planned and medically induced elective surgery under full anesthesia; b) by local anesthesia in subjects without a medically induced surgery

Intervention type: PROCEDURE
Intervention: taste bud biopsy
Description: Taste buds will be surgically removed a) during a planned and medically induced elective surgery under full anesthesia; b) by local anesthesia in subjects without a medically induced surgery

Intervention type: DIAGNOSTIC_TEST
Intervention: oral glucose tolerance test
Description: 75g glucose will be applied in drinking water following blood sample collection to evaluate glucose, insulin and C-peptide level.

Intervention type: DIAGNOSTIC_TEST
Intervention: oral glucose tolerance test
Description: 75g glucose will be applied in drinking water following blood sample collection to evaluate glucose, insulin and C-peptide level.

Intervention type: DIAGNOSTIC_TEST
Intervention: Taste sensitivity
Description: Subjects are given taste strips with 4 concentrations per each taste quality of sweet, sour, salty, bitter and umami in a pseudo-randomized manner. Subjects are asked to identify the taste quality, state the intensity, preference and certainty.

Intervention type: DIAGNOSTIC_TEST
Intervention: Taste sensitivity
Description: Subjects are given taste strips with 4 concentrations per each taste quality of sweet, sour, salty, bitter and umami in a pseudo-randomized manner. Subjects are asked to identify the taste quality, state the intensity, preference and certainty.

Intervention type: DIAGNOSTIC_TEST
Intervention: olfactory function
Description: Subjects will be presented 16 different sniffing sticks in a randomized order, each for about 4seconds. People are then asked to identify the smell by choosing one out of 4 options (forced choice).

Intervention type: DIAGNOSTIC_TEST
Intervention: olfactory function
Description: Subjects will be presented 16 different sniffing sticks in a randomized order, each for about 4seconds. People are then asked to identify the smell by choosing one out of 4 options (forced choice).

Intervention type: DIAGNOSTIC_TEST
Intervention: taste bud density
Description: The number of taste buds on the anterior tongue will be determined by colouring the tongue surface with food colour. Taste buds will apply more reddish as compared to non-taste tissue. Based on a digital photography the number of taste buds per subjects is counted manually.

Intervention type: DIAGNOSTIC_TEST
Intervention: taste bud density
Description: The number of taste buds on the anterior tongue will be determined by colouring the tongue surface with food colour. Taste buds will apply more reddish as compared to non-taste tissue. Based on a digital photography the number of taste buds per subjects is counted manually.

Intervention type: DIAGNOSTIC_TEST
Intervention: anthropometry
Description: Anthropometric data collection will include measures of body height, body weight, arm-, upper- and lower leg circumferences, waist- and hip circumferences and a bioimpedance analysis to obtain data about body composition.

Intervention type: DIAGNOSTIC_TEST
Intervention: anthropometry
Description: Anthropometric data collection will include measures of body height, body weight, arm-, upper- and lower leg circumferences, waist- and hip circumferences and a bioimpedance analysis to obtain data about body composition.

Intervention type: OTHER
Intervention: biospecimen collection
Description: Blood and saliva samples will be taken as well as a tongue swab.

Intervention type: OTHER
Intervention: biospecimen collection
Description: Blood and saliva samples will be taken as well as a tongue swab.

Intervention type: OTHER
Intervention: questionnaires
Description: Through the use of several questionnaires, data about eating behavior, food preferences, life style factors and other will be obtained.

Intervention type: OTHER
Intervention: questionnaires
Description: Through the use of several questionnaires, data about eating behavior, food preferences, life style factors and other will be obtained.