THE ROLE OF ANTI-NUTRIENT IN FOOD ABSORPTION
TABLE OF CONTENTS
Title Page- – – – – – – – – i
Certification- – – – – – – – ii
Dedication- – – – – – – – – iii
Acknowledgements- – – – – – – iv
Table of Contents- – – – – – – – v-vii
CHAPTER ONE: INTRODUCTION – – – 1
1.1 Antinutrient in Legumes – – – – – – 2
CHAPTER TWO: DEFINITION OF NTINUTRIENT – 4
2.1 Mechanism of Action of Antinutrient- – – – – 5
2.1.1 Preventing Nutrient Uptake- – – – – – 5
2.1.2 Enzyme Inhibition – – – – – – – 6
2.2 Occurrence of Antinutrients- – – – – – 7
2.3 Antinutrients- – – – – – – – 8
2.4 Classification of Antinutrients- – – – – – 10
CHAPTER THREE: THE ROLE OF ANTINUTRIENTS IN FOOD ABSORPTION
3.1 Lectins- – – – – – – – – 13
3.2 Protease inhibition- – – – – – – 14
3.3 Alpha-Galactosides- – – – – – – 15
3.4 Saponins – – – – – – – – – 16
3.5 Phytic Acid- – – – – – – – – 15
3.6 Tannins- – – – – – – – – 19
3.7 Oxalate – – – – – – – – – 20
CHAPTER FOUR: SUMMARY AND RECOMMENDATION
4.1 Summary- – – – – – – – – 21
4.2 Conclusion- – – – – – – – –
References
CHAPTER ONE
1.0 INTRODUCTION
When adapting to, or maintaining, a plant-based diet that contains legumes, it is important to have some prior knowledge regarding nutritional factors since the bioavailability of minerals is considered to be lower in legumes. This is mainly due to the presence of absorption inhibitors such as polyphenols and phytates (Mayer et al., 2021) or so called antinutritional factors (ANF) (Sharan et al., 2021). Furthermore, legumes have an unbalanced content of essential amino acids (Sandstrom et al., 2012) which increases the risk of nutritional deficiency (Livsmedelsverket, 2021). By complementing the legumes with other sources of amino acids, either animal originated products or cereal based goods, a satisfactory combination of amino acids can be achieved (Sandstrom et al., 2012).
According to Platel and Srinivasan (2016), both developed and developing countries have a widespread problem with micronutrients deficiencies, mainly caused by poor bioavailability of nutrients from plant-based foods. Thereof, micronutrients such as iron, vitamin A, zinc and iodine (Platel & Srinivasan, 2016) are most likely to be missing if a vegetarian diet is not varied enough (Sanders, 1999). Thus, a vegan diet has to be supplemented with vitamin B12 through enriched products or supplements, despite variation (Craig, 2009). Certain groups of the population including women of childbearing age, infants, children and adolescents have a higher requirement for some micronutrients such as iron (Sandstrom et al., 2012).
1.1 Antinutrients in legumes
Legumes are a naturally good source of protein and other nutrients such as minerals and vitamins (Hall et al. 2017) which makes them an important pillar in a plant based diet (Bal, 2007). However, the concentration of nutrients is not necessarily. This is why the concept of bioavailability was developed, to define the proportion of an ingested nutrient, available for storage deposition in the body or its utilization in metabolic processes (Gregory III, 2017). Legumes contain components, other than the classic nutrients. Substances such as phytic acid and lectins belong to the bioactive compounds and if they are being frequently consumed, they can affect the human metabolism. These effects can be regarded as either positive, negative or both depending on the form ingested and dosage. Due to their sometimes negative effects, the bioactive compounds are being referred to as antinutrients or ANF. Negative effects include inhibition of mineral uptake and protein digestion (Campo s-Vega, Loarca-Piña & Oomah, 2010) leading to interactions with the protein functions and functional properties of legumes-based food to some extent (Sharan et al., 2021). ANF can also disrupt the nutritional adequacy of a legume-based product by causing an improper uptake of nutrients (Campos-Vega, Loarca-Piña and Oomah, 2010). Therefore, it is crucial to know how different antinutrients affect the availability of nutrients to the human body.
