Investigating the dietary intake and metabolic disease in South Asian and Caucasian populations

• Main Author: Foroughifar, Neda
• Format: Dissertation
• Language: English
• Published: Imperial College London 2018
• DOI: 10.25560/59033

There is a high prevalence of T2DM and CHD in South Asians who have migrated to developed countries including UK, compared to their Caucasian counterparts. Studies investigating genetics, obesity, and physical activity have not been able to explain the prevalence of metabolic disorders in South Asians. Dietary intake might play a role in the development of metabolic diseases suggested by published work showing contradictory result. We hypothesized that detailed dietary assessment will lead to understanding the high prevalence of metabolic disorders in South Asians. The data of a sub-cohort from LOLIPOP was used to re-examine the dietary intake and metabolic disorders in groups without and with CHD in South Asians versus Caucasians. Initially the estimated dietary records were analysed which revealed higher carbohydrate but lower SFA and alcohol intakes in both South Asian groups, a dietary profile which is not associated with metabolic disorders. It is possible that food components which are not shown in traditional dietary assessment play a role in metabolic diseases. Thus, I undertook metabolomics profiling method for serum and duplicate diet samples with the intention to get further insight in the relationship between dietary intake and metabolic disorders. 1HNMR technique was applied for both samples. The analysis for serum and food samples showed no difference between South Asians and Caucasians in the UK. But the comparison between South Asians in the UK versus India revealed higher levels of valine, citrate, and glucose but, lower dimethylglycine and phenylalanine. Food analysis revealed higher levels of citrate, glucose, alanine, and glycerol whereas, fumarate and phenylalanine were lower in South Asians in UK. Most of the identified compounds play a role in energy metabolism which raises the possibility of the effect of diet composition on metabolic disorders. Further investigation is required applying a targeted metabolomics study to identify specific pathways.