Selvakumar Subramaniam

Dietary fat taste, a distinct gustatory modality that greatly influences food choice and energy intake, is primarily mediated by the lingual receptors CD36 and GPR120. Recent studies show that both short‐term and long‐term physical activity can modulate sensitivity to long‐chain fatty acids, which can lead to changes in dietary patterns and preferences for high‐fat foods. This review specifically examines the effects of exercise on the perception of fat taste by integrating findings from human and animal studies that examine alterations in detection thresholds, suprathreshold intensity ratings, and hedonic responses to fatty stimuli. We explore mechanistic pathways by which exercise influences fat taste, such as changes in hormones that regulate appetite, systemic anti‐inflammatory processes that may enhance or attenuate CD36/GPR120 signaling in taste bud cells, and neural adaptations within gustatory cortices. The implications of exercise‐induced alterations in fat‐taste acuity for appetite regulation, dietary behavior, and long‐term metabolic health are discussed, with particular attention to how increased sensitivity may promote reduced consumption of energy‐dense foods. Finally, we highlight significant gaps in human translational research regarding the magnitude and persistence of exercise‐induced fat‐taste plasticity and propose targeted future studies to employ fat‐taste modulation as a cutting‐edge strategy for obesity prevention and public health nutrition interventions.

Taster categorisation uses bitter thiourea compounds like propylthiouracil (PROP) and phenylthiocarbamide (PTC), which are frequently associated with amino acid alterations at positions 49, 262 and 296 in human taste 2 receptor member 38 (hTAS2R38). Since the hTAS2R38 protein lacked a crystallographic structure, it was modelled using contact‐guided iterative threading assembly refinement, its residues were mutated and refined, and the binding pocket area and volume were assessed using CASTp. Bitter thiourea molecules were docked using the ligand extra precision module and the receptor–ligand complex was manually positioned in a fully hydrated, equilibrated 1‐palmitoyl‐2‐oleoylphosphatidylcholine bilayer using the CHARMM GUI membrane constructor, a 100 ns simulation was carried out using the Desmond program. Analysis revealed that the PROP binds to the allosteric hydrophobic pocket of hTAS2R38 and forms a hydrogen bond with ASN190. The native structure (hTAS2R38_PAV) has a higher glide energy (−24.164 kcal/mol) and docking score (−7.212 kcal/mol) than mutants, corroborating our taste preference study. In contrast, PTC lacks hydrogen bonds in the binding pocket but exhibits pi–pi stacking interactions with the native structure. Structures with mutations at the 49th or 296th position showed the largest root mean square deviations and fluctuations. A triple mutation increases surface area and volume, making the 262nd position critical to the binding pocket. These results highlight the functional roles of these three residues in hTAS2R38.

Recent advancements in sensory research have brought to light the intricate relationship between taste perception and the oral microbiota, prompting investigations into their influence on human health, particularly in the context of dietary preferences and obesity. This review aims to update the current understanding of how oral microbiota influence taste perception and dietary choices, elucidating shared metabolic pathways between food processing and oral bacteria. Further, this review outlines the mechanisms underlying taste perception, emphasising the role of taste receptors and taste buds in shaping sensory experiences influenced by genetic and environmental factors. Notably, we explore the bidirectional relationship between oral microbiota and taste sensitivity, highlighting the potential impact of microbial composition on taste perception thresholds and implications for dietary habits and health outcomes, such as obesity and dental caries. However, significant research gaps remain, particularly in the understanding of the molecular mechanisms linking oral microbiota with taste sensitivity, as well as the long-term effects of microbiota-targeted interventions. Future research should focus on longitudinal studies and experimental interventions to explore these connections more deeply, offering insights into potential strategies for promoting healthier dietary behaviours and managing diet-related non-communicable diseases.

Genetic variations in taste receptors are associated with gustatory perception and obesity, which in turn affects dietary preferences. Given the increasing tendency of people with obesity choosing sweet, high-fat meals, the current study assessed the cross-regulation of two polymorphisms of the sweet taste receptor (T1R2/T1R3), rs35874116 and rs307355, on fat sensitivity in Indian adults. We investigated the association between taste sensitivity and BMI in the T1R2, T1R3, and CD36 polymorphic and non-polymorphic groups. The general labelled magnitude scale (gLMS) was used to assess the taste sensitivity of 249 participants in addition to anthropometric data. TaqMan Probe-based RT-PCR was employed to determine the polymorphisms. Additionally, the colorimetric method utilizing 3, 5-dinitro salicylic acid was used to evaluate the participants' salivary amylase activity. The mean detection thresholds for linoleic acid (LA) and sucrose were greater in individuals with obesity (i.e., 0.97 ± 0.08 mM and 0.22 ± 0.02 M, respectively) than in healthy adults (p < 0.0001), indicating lower sensitivity. Moreover, it was found that a greater proportion of persons with obesity fall into the polymorphic groups (i.e., 52% with genotype CD36 AA, 44% with genotype T1R2 CC, and 40% with genotype T1R3 TT). All three single nucleotide polymorphisms support the Hardy–Weinberg equilibrium (p = 0.78). The Pearson correlation analysis between LA and the sucrose detection threshold revealed a significant (p < 0.0001) positive relationship with an r value of 0.5299. Moreover, salivary amylase activity was significantly (p < 0.05) higher in the polymorphic sub-groups. The results of our study imply that genetic variations in T1R2/T1R3 receptors affect perception of both sweetness and fat, which may have an effect on obesity.