29/06/09 A new study from Dutch research organization TNO demonstrates that the body shape of overweight 29/06/09 people influences how their fat tissue responds to dietary fats. The distribution of body fat in overweight people might therefore represent an important consideration when providing dietary advice. Dr. M. Radonjic and colleagues at TNO conclude this in their latest study.

This study compared people with an “apple” shape (predominant fat deposition around the waist) to those with “pear” shapes (fat depositions on the hips and thighs). This research provides important insights into the effect of body fat distribution on the processing of dietary fats. The observation also underscores the relevance of personalized dietary recommendations for improving obesity-associated disorders.

Prompted by the growing need to manage obesity-related disorders, numerous investigations aim to optimize the diet of obese people as a way of improving their health. One of the accepted approaches is shifting from a diet rich in long-chain poly unsaturated fatty acids (PUFA) to a diet based on medium-chain fatty acids (MCT). This dietary shift has been shown to be potentially beneficial due to the rapid breakdown of MCTs and their routing directly to the liver instead of being stored as fat tissue. The TNO findings, however, indicate that the extent of the favorable effect of consumption of MCT-rich diets strongly depends on the body fat distribution of an obese individual.

Principal investigator Marijana Radonjic explains the relevance of her research results: “By measuring the activity of all the genes in the fat tissue of obese volunteers, we were able to identify individual responses to the different fats. Interestingly, we found that the effects were opposite in “apple type” and “pear type” subjects. A MCT-rich diet increases the expression of genes responsible for driving metabolic processes in the fat tissue of “pear type” individuals, but has a contrary effect in “apple type” individuals. In addition to suppression of metabolic genes, MCT-rich diet causes inflammation in fat tissue of “apple type” individuals. Therefore, we show for the first time that although MCT-rich diet may have positive effects for “pears”, it has adverse effect on obesity-related complications of “apples”. Our findings highlight the need for the personalized strategies to improve health. Using genome-wide gene expression profiling has proven to be successful as a means of determining person specific response to dietary interventions. This methodology is receiving increasing attention in field of personalized health.”

In a cross-over study, 11 mildly obese male volunteers were selected to consume a margarine containing predominantly either medium chain fatty acids (MCT) or long chain fatty acids (PUFA). Each of two diets was given to each subject for 3 weeks, with a period of 6 weeks in between. After three weeks on a specific diet, fat tissue biopsies were taken from subject’s abdomen and gene expression in these biopsies was analyzed. This analysis lead to the observations mentioned above.

Nutrigenomics investigates molecular relationships between dietary components and genes, proteins and/or metabolites on a large scale, to find strategies to improve human health. By monitoring the activity of all genes (transcriptomics), proteins (proteomics) and metabolites (metabolomics) in desired nutritional condition allows researchers to characterize a complex relationship between nutrients and physiological properties of an organism. Due to its sensitivity, nutrigenomics is successful in segmenting a group based on personalized responses to mild diet changes. Therefore, nutrigenomics holds great potential for refining dietary recommendations and dietary product-associated health claims. TNO has an internationally recognized position in both academic- and industry-based nutrigenomics research. The study presented above is a part of TNO’s growing portfolio in nutrigenomics of fat tissue biopsies within a human studies setting. The results of this study are not specific enough to be considered as a general advice.