BackgroundVitamin B12 is an essential micronutrient in humans needed for health maintenance. Deficiency of vitamin B12 has been linked to dietary, environmental and genetic factors. Evidence for the genetic basis of vitamin B12 status is poorly understood. However, advancements in genomic techniques have increased the knowledge-base of the genetics of vitamin B12 status. Based on the candidate gene and genome-wide association (GWA) studies, associations between genetic loci in several genes involved in vitamin B12 metabolism have been identified.ObjectiveThe objective of this literature review was to identify and discuss reports of associations between single-nucleotide polymorphisms (SNPs) in vitamin B12 pathway genes and their influence on the circulating levels of vitamin B12.MethodsRelevant articles were obtained through a literature search on PubMed through to May 2017. An article was included if it examined an association of a SNP with serum or plasma vitamin B12 concentration. Beta coefficients and odds ratios were used to describe the strength of an association, and a P < 0.05 was considered as statistically significant. Two reviewers independently evaluated the eligibility for the inclusion criteria and extracted the data.ResultsFrom 23 studies which fulfilled the selection criteria, 16 studies identified SNPs that showed statistically significant associations with vitamin B12 concentrations. Fifty-nine vitamin B12-related gene polymorphisms associated with vitamin B12 status were identified in total, from the following populations: African American, Brazilian, Canadian, Chinese, Danish, English, European ancestry, Icelandic, Indian, Italian, Latino, Northern Irish, Portuguese and residents of the USA.ConclusionOverall, the data analyzed suggests that ethnic-specific associations are involved in the genetic determination of vitamin B12 concentrations. However, despite recent success in genetic studies, the majority of identified genes that could explain variation in vitamin B12 concentrations were from Caucasian populations. Further research utilizing larger sample sizes of non-Caucasian populations is necessary in order to better understand these ethnic-specific associations.

Myrcene (β-myrcene) is an abundant monoterpene which occurs as a major constituent in many plant species, including hops and cannabis. It is a popular flavouring and aroma agent (food additive) used in the manufacture of food and beverages. This review aims to report on the occurrence, biological and toxicological profile of β-myrcene. The main reported biological properties of β-myrcene—anxiolytic, antioxidant, anti-ageing, anti-inflammatory, analgesic properties—are discussed, with the mechanisms of activity. Here we also discuss recent data regarding the safety of β-myrcene. Overall, β-myrcene has shown promising health benefits in many animal studies. However, studies conducted in humans is lacking. In the future, there is potential for the formulation and production of non-alcoholic beers, functional foods and drinks, and cannabis extracts (low in THC) rich in β-myrcene.

Recent evidence suggests that lifestyle factors influence the association between the Melanocortin 4 receptor (MC4R) and Transcription Factor 7-Like 2 (TCF7L2) gene variants and cardio-metabolic traits in several populations; however, the available research is limited among the Asian Indian population. Hence, the present study examined whether the association between the MC4R single nucleotide polymorphism (SNP) (rs17782313) and two SNPs of the TCF7L2 gene (rs12255372 and rs7903146) and cardio-metabolic traits is modified by dietary factors and physical activity. This cross sectional study included a random sample of normal glucose tolerant (NGT) (n = 821) and participants with type 2 diabetes (T2D) (n = 861) recruited from the urban part of the Chennai Urban Rural Epidemiology Study (CURES). A validated food frequency questionnaire (FFQ) was used for dietary assessment and self-reported physical activity measures were collected. The threshold for significance was set at P = 0.00023 based on Bonferroni correction for multiple testing [(0.05/210 (3 SNPs x 14 outcomes x 5 lifestyle factors)]. After Bonferroni correction, there was a significant interaction between the TCF7L2 rs12255372 SNP and fat intake (g/day) (Pinteraction = 0.0001) on high-density lipoprotein cholesterol (HDL-C), where the ‘T’ allele carriers in the lowest tertile of total fat intake had higher HDL-C (P = 0.008) and those in the highest tertile (P = 0.017) had lower HDL-C compared to the GG homozygotes. In a secondary analysis of SNPs with the subtypes of fat, there was also a significant interaction between the SNP rs12255372 and polyunsaturated fatty acids (PUFA, g/day) (Pinteraction<0.0001) on HDL-C, where the minor allele carriers had higher HDL-C in the lowest PUFA tertile (P = 0.024) and those in the highest PUFA tertile had lower HDL-C (P = 0.028) than GG homozygotes. In addition, a significant interaction was also seen between TCF7L2 SNP rs12255372 and fibre intake (g/day) on HDL-C (Pinteraction<0.0001). None of the other interactions between the SNPs and lifestyle factors were statistically significant after correction for multiple testing. Our findings indicate that the association between TCF7L2 SNP rs12255372 and HDL-C may be modified by dietary fat intake in this Asian Indian population.

As individuals seek increasingly individualised nutrition and lifestyle guidance, numerous apps and nutrition programs have emerged. However, complex individual variations in dietary behaviours, genotypes, gene expression and composition of the microbiome are increasingly recognised. Advances in digital tools and artificial intelligence can help individuals more easily track nutrient intakes and identify nutritional gaps. However, the influence of these nutrients on health outcomes can vary widely among individuals depending upon life stage, genetics and microbial composition. For example, folate may elicit favourable epigenetic effects on brain development during a critical developmental time window of pregnancy. Genes affecting vitamin B12 metabolism may lead to cardiometabolic traits that play an essential role in the context of obesity. Finally, an individual’s gut microbial composition can determine their response to dietary fibre interventions during weight loss. These recent advances in understanding can lead to a more complete and integrated approach to promoting optimal health through personalised nutrition, in clinical practise settings and for individuals in their daily lives. The purpose of this review is to summarise presentations made during the DSM Science and Technology Award Symposium at the 13th European Nutrition Conference, which focused on personalised nutrition and novel technologies for health in the modern world.

The Mediterranean diet (MedDiet) is considered as a good example of a healthy dietary pattern that has protective effects on obesity. The aim of the present study was to assess the adherence of adults from three Gulf countries (Saudi Arabia, Oman, and Kuwait) to the MedDiet and its association with obesity risk. A cross-sectional study was conducted on 961 men and women (75.7%) aged 20–55 years old. Waist circumference (WC), and hip circumference (HC) were measured waist/hip ratio (WHR) and body mass index (BMI) were calculated. A validated 14-item Questionnaire was used to measure adherence to MedDiet. The mean of the adherence to MedDiet score was 5.9 ± 2.03 for the total sample. An inverse association was observed between the adherence to MedDiet and BMI after adjusting for potential confounders (p = 0.0003 in total participants, and p = 0.001 in women only). A protective effect was seen with a higher adherence to the MedDiet on HC, suggesting that a greater adherence to the MedDiet was associated with a decreased HC (p = 0.04 in total participants, and p = 0.01 in women only). In conclusion, low adherence to the MedDiet among participants from three gulf countries was associated with increased obesity indicators, BMI, and HC.