Chocolate and the sweet taste receptor gene TAS1R2
Last Updated on February 1, 2018 by Joseph Gut – thasso
January 31, 2018 – Chocolate and the sweet taste receptor gene TAS1R2 may make the life of some obese children and adolescents rather difficult in that genetic variations in TAS1R2 appear related to chocolate powder and dietary fiber intake in these young individuals.
This comes out of a study by a research team at the Faculty of Medicine, University of Sao Paulo, Sao Paulo, Brazil, just published in the Journal of Personalized Medicine (JPM) on January 29, 2018. Childhood obesity is a major public health problem. It has a direct impact on the quality of life of children and adolescents, as well as on their future risk of developing chronic diseases. Dietary patterns rich in fats and sugars and lacking dietary fibers, vitamins, and minerals, as well as lack of physical exercise have been associated with the rise of obesity prevalence.
However, factors that contribute to the preference for foods rich in these nutrients are not well established. Taste is recognized as an important predictor of food choices, and polymorphisms in taste-related genes may explain the variability of taste preference and food intake. The aim of this research was therefore to evaluate the influence of polymorphisms of the sweet taste receptor gene TAS1R2 on diet and metabolic profile in obese children and adolescents.
The research team carried out a cross-sectional study with 513 obese children and adolescents and 135 normal-weight children. They performed a molecular study on the single nucleotide polymorphisms (SNPs) rs9701796 and rs35874116 of the sweet taste receptor gene TAS1R2, and dietary intake, anthropometric parameters (weight, height, waist circumference, waist-to-height ratio (WHtR)), and metabolic profile (including fasting glucose, insulin, triglyceride, high-density lipoprotein (HDL)–cholesterol, and leptin levels) were analyzed. The variant rs9701796 of TAS1R2 was associated with increased waist-height ratio, as well as with a higher chocolate powder intake in obese children. In contrast, the variant rs35874116 TAS1R2 was associated with a lower dietary fiber intake.
This study illustrates that there is probably no relationship between genotypes of TAS1R2 and risk of obesity. However, obese adolescents carrying the serine allele of SNP rs9701796 in TAS1R2 showed higher waist-to-height ratio and chocolate powder intake, whereas those carrying the valine allele of SNP rs35874116 in TAS1R2 were characterized by lower dietary fiber intake, meaning that variations in on single gene, in this case of TAS1R2 might contribute to difficulties in controlling much needed behaviour, like reducing eating chocolate for individuals who would need it most.
Once in a while, one might have to restrain from devastating judgements on the behaviour of individuals, who just can’t help themselves, because it is in their genes. Carriers of allelic variation in TAS1R2, obese or not, might just be one of those examples. Needless to say that the vast majority of the affected individuals do not yet have the slightest idea where their urge for chocolate (powders) and their resistance to eating of fibres might come from. This is the true pity. The peers of these individuals (children, obese children, adolescents, and grown up people with excessive chocolate eating habits) most likely also have not the slightest clue, why their loved ones can’t help but crave for chocolate instead of fibers. TAS1R2 might be one of the answers.