A Systematic Review of the Effect of Gene-Lifestyle Interactions on Metabolic-Disease-Related Traits in South Asian Populations.

CONTEXT: Recent data from the South Asian subregion have raised concern about the dramatic increase in the prevalence of metabolic diseases, which are influenced by genetic and lifestyle factors. OBJECTIVE: The aim of this systematic review was to summarize the contemporary evidence for the effect of gene-lifestyle interactions on metabolic outcomes in this population. DATA SOURCES: PubMed, Web of Science, and SCOPUS databases were searched up until March 2023 for observational and intervention studies investigating the interaction between genetic variants and lifestyle factors such as diet and physical activity on obesity and type 2 diabetes traits. DATA EXTRACTION: Of the 14 783 publications extracted, 15 were deemed eligible for inclusion in this study. Data extraction was carried out independently by 3 investigators. The quality of the included studies was assessed using the Appraisal Tool for Cross-Sectional Studies (AXIS), the Risk Of Bias In Non-randomized Studies-of Interventions (ROBINS-I), and the methodological quality score for nutrigenetics studies. DATA ANALYSIS: Using a narrative synthesis approach, the findings were presented in textual and tabular format. Together, studies from India (n = 8), Pakistan (n = 3), Sri Lanka (n = 1), and the South Asian diaspora in Singapore and Canada (n = 3) reported 543 gene-lifestyle interactions, of which 132 (∼24%) were statistically significant. These results were related to the effects of the interaction of genetic factors with physical inactivity, poor sleep habits, smoking, and dietary intake of carbohydrates, protein, and fat on the risk of metabolic disease in this population. CONCLUSIONS: The findings of this systematic review provide evidence of gene-lifestyle interactions impacting metabolic traits within the South Asian population. However, the lack of replication and correction for multiple testing and the small sample size of the included studies may limit the conclusiveness of the evidence. Note, this paper is part of the Nutrition Reviews Special Collection on Precision Nutrition. SYSTEMATIC REVIEW REGISTRATION: PROSPERO registration No. CRD42023402408.

A Dietary Intervention in Adults with Overweight or Obesity Leads to Weight Loss Irrespective of Macronutrient Composition.

Obesity is a critical public health issue, necessitating effective weight loss interventions. While various dietary regimens have been explored, individual responses to interventions often vary. This study involved a 3-month dietary intervention aiming at assessing the role of macronutrient composition and the potential role of genetic predisposition in weight loss among Greek adults. This randomized clinical trial followed the CONSORT principles, recruiting 202 participants overall; 94 received a hypocaloric, high-protein diet and 108 received a high-carbohydrate, hypocaloric diet. Genetic predispositions were assessed through 10 target variants known for their BMI associations. Participants' weight and BMI values were recorded at baseline and post-intervention (n = 202 at baseline, n = 84 post-intervention) and an imputation method was applied to account for the observed missing values. Participants experienced a statistically significant weight loss across all dietary regimens (p < 0.001). Genetic analyses did not display statistically significant effects on weight loss. No significant differences in weight loss were observed between macronutrient groups, aligning with the POUNDS Lost and DIETFITS studies. This study underscores the importance of dietary interventions for weight loss and the potential contributions of genetic makeup. These findings contribute to obesity management within the Greek population and support the need for further research in personalized interventions.

Informing Evidence-based Practice in Nutritional Genomics: An Educational Needs Assessment of Nutrition Care Providers in Canada.

Purpose: To investigate why Canadian nutrition care providers choose, or not, to integrate nutritional genomics into practice, and to evaluate the nutritional genomics training/education experiences and needs of nutrition providers in Canada, while comparing those of dietitians to non-dietitians.Methods: A cross-sectional online survey was distributed across Canada from June 2021 to April 2022.Results: In total, 457 healthcare providers (HCPs) [n = 371 dietitians (81.2%)] met the inclusion criteria. The majority (n = 372; 82.1%) reported having no experience offering nutritional genomics to clients (n = 4 did not respond). Of the 81 respondents with experience (17.9%), the most common reason to integrate nutrigenetic testing into practice was the perception that clients would be more motivated to change their eating habits (70.4%), while the most common reason for not integrating such tests was the perception that the nutrigenetic testing process is too complicated (n = 313; 84.1%). Dietitians were more likely than non-dietitians to view existing scientific evidence as an important educational topic (p = 0.002). The most selected useful educational resource by all HCPs was clinical practice guidelines (n = 364; 85.4%).Conclusions: Both dietitians and non-dietitians express a desire for greater nutritional genomics training/education; specific educational needs differ by type of HCP. Low implementation of nutrigenetic testing may be partly attributed to other identified barriers.

Homocysteine, blood pressure and gene-diet interactions in relation to vascular function measures of black South Africans.

BACKGROUND AND AIMS: We investigated circulating homocysteine (Hcy), a cardiovascular disease (CVD) risk factor, examining its dietary associations to provide personalized nutrition advice. This study addressed the inadequacy of current dietary interventions to ultimately address the disproportionately high incidence of CVD in Black populations. METHODS AND RESULTS: Cross-sectional analyses of 1,867 Black individuals of the PURE-SA study allowed the identification of dietary intake and cardiovascular measure interactions on three sub-categories: (1) normal blood pressure (BP), hypertension or Hcy-related hypertension (H-type), (2) low, normal or high Hcy concentrations, and (3) Hcy-related genetic combinations. Favorable body composition, but adverse dietary intake and cardiovascular determinants, were observed in higher Hcy categories. H-types, compared to regular hypertensives, had higher alcohol and lower macronutrient and micronutrient consumption. Inverse associations with carotid-radial pulse wave velocity were evident between monounsaturated fatty acid (FA) consumption and H-type hypertension as well as polyunsaturated FA and CBS883/ins68 TT carriers. Energy intake was positively associated with vascular cell adhesion molecule-1 (VCAM-1) in variant CBST883C/ins68 and CBS9276 GG carriers. VCAM-1 was also positively associated with plant protein intake in CBS9276 GG and MTR2756 AA carriers and negatively with total protein intake and CBS9276 GG carriers. Alcohol intake was positively associated with intercellular adhesion molecule-1 in MTR2756 minor allele carriers. CONCLUSION: Because Hcy gene-diet interactions are evident, personalized nutrition, by adjusting diets based on genetic profiles (e.g., CBS and MTR variations) and dietary interactions (e.g., FAs and proteins), can enhance cardiovascular outcomes by managing Hcy and related hypertension in genetically susceptible individuals.

Effect of ADORA2A Gene Polymorphism and Acute Caffeine Supplementation on Hormonal Response to Resistance Exercise: A Double-Blind, Crossover, Placebo-Controlled Study.

Previous studies have reported that TT genotype carriers of the adenosine A2a receptor (ADORA2A) gene rs5751876 polymorphism have better ergogenic and anti-inflammatory responses to caffeine intake compared to C allele carriers. The aim of the present study was twofold: (1) to investigate the association of the ADORA2A rs5751876 polymorphism with acute caffeine supplementation on hormonal (growth hormone and testosterone) response to resistance exercise (RE); (2) to examine the relationship between the rs5751876 polymorphism and the resting levels of growth hormone and testosterone in athletes who are light caffeine consumers. A double-blind, crossover, placebo-controlled study involving 30 resistance-trained men (age 21.7 ± 4.1) was conducted to assess the impact of caffeine supplementation on serum growth hormone (GH) and testosterone (TS) levels before, immediately after, and 15 min post-RE. One hour before engaging in resistance exercise, subjects were randomly administered 6 mg of caffeine per kg of body mass or a placebo (maltodextrin). After a 7-day washout period, the same protocol was repeated. Resting testosterone and growth hormone levels were examined in the sera of 94 elite athletes (31 females, age 21.4 ± 2.8; 63 males, age 22.9 ± 3.8). Caffeine consumption led to significantly greater increases in GH and TS in men with the TT genotype compared to C allele carriers. Furthermore, in the group of athletes, carriers of the TT genotype had significantly higher testosterone (p = 0.0125) and growth hormone (p = 0.0365) levels compared to C allele carriers. In conclusion, the ADORA2A gene rs5751876 polymorphism may modify the effect of caffeine intake on the hormonal response to exercise.

Community pharmacy professionals' knowledge, attitude, and practice toward nutrition and lifestyle counseling in Gondar City, Ethiopia.

Background: Community pharmacy professionals play a vital role in health care, have a greater impact on public health programs, and play a critical role in patient counseling for both non-pharmacological and pharmacological management. This study aimed to evaluate the knowledge, attitude, and practice of community pharmacy professionals toward nutrition and lifestyle counseling in Gondar City, Ethiopia. Methods: A cross-sectional survey was undertaken in Northwestern Ethiopia from May to June 2021. Face-to-face structured interviews were performed to collect data using a specially created questionnaire. Descriptive, independent t-test, and one-way ANOVA analyses were used. A significant difference was defined as a p-value of less than 0.05. Results: This survey drew 100 community pharmacy professional from a pool of 105 participants, with a 95.2% response rate. More than a third of the participants (n = 43, 43%) defined medical nutrition therapy as the use of food to prevent disease, and almost half of the participants (n = 51, 51%) viewed therapeutic nutrition to be part of their job responsibilities. More than half (64%) believe that patients should be provided a combination of nutritional and pharmacological treatments in the majority of cases. The majority of participants (75%) gave patients counseling on drug-food interactions. Conclusion: The majority of community pharmacy professionals said they knew a lot about medical nutrition therapy and were enthusiastic about nutrition evaluation and medical nutrition therapy, they see these tasks as part of their job, and they practiced dietary counseling that was limited to pregnancy and chronic diseases.

Host genetics and nutrition.

Optimal nutrition is essential for health and physiological performance. Nutrition-related diseases such as obesity and diabetes are major causes of death and reduced quality of life in modern Western societies. Thanks to combining nutrigenetics and nutrigenomics, genomic nutrition allows the study of the interaction between nutrition, genetics and physiology. Currently, interrelated multi-genetic and multifactorial phenotypes are studied from a multiethnic and multi-omics approach, step by step identifying the important role of pathways, in addition to those directly related to metabolism. It allows the progressive identification of genetic profiles associated with specific susceptibilities to diet-related phenotypes, which may facilitate individualised dietary recommendations to improve health and quality of life.

Integrated Analysis of Genomic and Genome-Wide Association Studies Identified Candidate Genes for Nutrigenetic Studies in Flavonoids and Vascular Health: Path to Precision Nutrition for (Poly)phenols.

Flavonoids exert vasculoprotective effects in humans, but interindividual variability in their action has also been reported. This study aims to identify genes that are associated with vascular health effects of flavonoids and whose polymorphisms could explain interindividual variability in response to their intake. Applying the predetermined literature search criteria, we identified five human intervention studies reporting positive effects of flavonoids on vascular function together with global genomic changes analyzed using microarray methods. Genes involved in vascular dysfunction were identified from genome-wide association studies (GWAS). By extracting data from the eligible human intervention studies, we obtained 5807 differentially expressed genes (DEGs). The number of identified upstream regulators (URs) varied across the studies, from 227 to 1407. The search of the GWAS Catalog revealed 493 genes associated with vascular dysfunction. An integrative analysis of transcriptomic data with GWAS genes identified 106 candidate DEGs and 42 candidate URs, while subsequent functional analyses and a search of the literature identified 20 top priority candidate genes: ALDH2, APOE, CAPZA1, CYP11B2, GNA13, IL6, IRF5, LDLR, LPL, LSP1, MKNK1, MMP3, MTHFR, MYO6, NCR3, PPARG, SARM1, TCF20, TCF7L2, and TNF. In conclusion, this integrated analysis identifies important genes to design future nutrigenetic studies for development of precision nutrition for polyphenols.

Nutrigenetic and Epigenetic Mechanisms of Maternal Nutrition-Induced Glucolipid Metabolism Changes in the Offspring.

Maternal nutrition during pregnancy regulates the offspring's metabolic homeostasis, including insulin sensitivity and the metabolism of glucose and lipids. The fetus undergoes a crucial period of plasticity in the uterus; metabolic changes in the fetus during pregnancy caused by maternal nutrition not only influence fetal growth and development but also have a long-term or even life-long impact for the offspring. Epigenetic modifications, such as DNA methylation, histone modification, and non-coding RNAs, play important roles in intergenerational and transgenerational effects. In this context, this narrative review comprehensively summarizes and analyzes the molecular mechanisms underlying how maternal nutrition, including a high-fat diet, polyunsaturated fatty acid diet, methyl donor nutrient supplementation, feed restriction, and protein restriction during pregnancy, impacts the genes involved in glucolipid metabolism in the liver, adipose tissue, hypothalamus, muscle, and oocytes of the offspring in terms of the epigenetic modifications. This will provide a foundation for the further exploration of nutrigenetic and epigenetic mechanisms for integrative mother-child nutrition and promotion of the offspring's health through the regulation of maternal nutrition during pregnancy. Note: This paper is part of the Nutrition Reviews Special Collection on Precision Nutrition.