Differences in the functional activity of the brain when using sugar and low-calorie sweeteners

BACKGROUND. Eating foods with a high sugar content causes changes in the functioning of the cerebral systems, involving hedonic and homeostatic mechanisms, which may be one of the mechanisms for the formation of increased cravings for sweet foods, weight gain and the development of metabolic disorders. Low-calorie sweeteners are widely used as an alternative to sucrose. Changes in the activity of brain areas when using various low-calorie sweeteners that stimulate sweet taste receptors are poorly understood.

AIM. To study the features of functional activity of various brain regions in healthy volunteers using functional magnetic resonance imaging (fMRI) when consuming sugar and the low-calorie sweetener Erythritol (E968).

MATERIALS AND METHODS. The study included 12 volunteers with a normal body weight (BMI) <25 kg/m²). The study was performed on a Siemens Magnetom Prisma 3.0T MR tomograph. The MRI examination protocol included sequences for obtaining T2-weighted images and three-dimensional T1-weighted images to exclude structural pathology of the brain and obtain anatomical data, as well as a sequence for obtaining resting fMRI data.

RESULTS. The median age of the subjects was 25 years [24; 26]; the median BMI was 22.5 [20; 24.8]. According to fMRI data, when taking sugar, connections between the temporal zones and the visual cortex are activated, which may reflect enhanced sensory integration and motivational processing of food reward. The sweetener has an effect on functional connectivity; the connection between the structures of the cerebellum, parietal cortex and insular cortex is specifically weakened, which can be interpreted as a decrease in the involvement of integrative sensory-motivational networks active on an empty stomach.

CONCLUSION. A dynamic study of brain activity using fMRI showed a different pattern of activation of brain areas when consuming sugar and sweetener.

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