Sensitivity and preference for sweet taste during a long-term change in the dietary carbohydrate consumption

In a long-term (6 months) intervention study, the effect of a low-fat diet and a concomitant change in the simple (SCHO) to complex (CCHO) carbohydrate ratio on sensory thresholds and preferences was determined. 60 volunteers (30 male, 30 female) with a mean BMI of 30 kg/m2 were randomly assigned to three intervention groups: A: fat intake < 30 E%, SCHO/CCHO 3:2, (E%-energy percent) B: fat intake < 30 E%, SCHO/CCHO 2:3, C: fat intake 40-45 E%, SCHO/CCHO approx. 1. At five times (before, 3 times within and 6 months after the intervention period) the following measurements were carried out: detection threshold of the taste quality 'sweet', recognition of sweetness differences slightly above the threshold (sucrose concentration 5.0 g/l vs. 6.4 g/l) and hedonic assessment of sweetness. During the intervention, the detection threshold decreased significantly from 5.1 to 2.7 g/l sucrose in subjects with lower sugar intake (group B). The ability to detect sweetness differences between solutions containing 5.0 and 6.4 g/l sucrose increased in groups B and C. During intervention, the intensity perception decreased in all groups but more rapidly in group A with a high sugar intake. The preference of solutions with lower sucrose content increased in all groups.