Bioavailability of phytoestrogens in protein based food for weight management.

There are four main objectives from this work. Chapter 1 provides the general introduction and rationale of the studies presented in this thesis. The first objective is addressed in Chapter 2, which reviews the beneficial role of dietary lignans and isoflavones in weight reduction in raw and processed food. The data on phytoestrogen compounds are collected and compiled. The searching strategy aimed to find peer published studies. SCOPUS, CAB Abstract, and PubMed searches were carried out, followed by the aim of the objective. The data was then analyzed, and foods high in phytoestrogen compounds (lignans and isoflavones) were identified with the potential to be a source of weight loss. The second objective is presented in Chapter 3. It determines the effect of pickling, fermentation, germination, and brewing process on the lignan content of various foods Malaysian mostly consume. The lignans were measured by a validated extraction method followed by LC-MS-MS measurement. The third objective is addressed in Chapter 4. It accesses the bio-accessibility of these selected foods, which are high in lignan compounds. Two different approaches, simulated gastro-intestinal in-vitro digestion (INFO-GEST) and single batch in-vitro fermentation, were used for the lignan bioaccessibility. Then, the fourth objective is presented in Chapter 5. It observes the association between lignan intake in different types of plant-based food and obesity in the Netherlands. NQ-Plus Data (a longitudinal study on diet and health) was used as a data source. Finally, Chapter 6 summarizes and discusses the main outcomes, places them in a larger context, and recommendations for further research.