1.1 Food and nutrients Flashcards
Introduction
This section has a focus on basic nutrition. It outlines the macro and micronutrients and highlights those that have key roles our immune systems.
Objectives
The objectives of this section are to: introduce basic concepts and terminology related to food, nutrition and assessment of nutritional status; and appreciate the role nutrients and nutrition play in the optimal functioning of the immune system.
Structure of the session
This section consists of three sessions. The first provides an introduction to nutrients in food basic and the second discussed different methods of nutritional assessment. The final session discusses the synergistic relationship between undernutrition, morbidity and mortality.
Overview
We know that it is important to eat well, that we need a variety of food in our diets to provide all the nutrients that our bodies need in order to grow, repair and function properly. We know that a bad diet can lead to malnutrition either via obesity & non communicable diseases (NCD’s) or undernutrition leading to immune incompetence & morbidity from disease.The nutrients are classified by how much bulk they provide in the diet: macro-nutrients - carbohydrate, fat, protein and micro-nutrients – vitamins and minerals
Overview
Daily nutrient requirements can be a useful tool, but we don’t typically eat ‘nutrients’ we eat ‘foods’. These days, more relatable terms, such as ‘the Mediterranean diet’ or ‘eat 5 a day’ fruit and vegetables are used and may be more suitable to the layman. This session is a brief overview of nutrition and outlines different nutrients and their important functions in the body relating to health and response to infection.
Learning objectives
After working through this session, you will be better able to name; and explain the roles of nutrients with known roles in immune function: describe the roles and food sources of the important macro and micronutrients in the diet; understand how different foods contribute to the nutritional value of a daily diet; and discuss the roles of both macronutrients and some micronutrients in immune function.
Key terms Amino acids:
Amino acids are the building blocks of proteins. Digestion breaks down proteins to amino acids before absorption. New proteins are then built from them, or they are used as an energy source.
Key terms Anorexia:
Loss of appetite leading to a reduction in food intake.
Key terms Basal metabolic rate (BMR):
Amount of energy expended in the basal state i.e., at complete rest.
Key terms Catabolism:
Metabolic pathways that break down body tissue and releases energy.
Key terms Dietary Fibre:
Indigestible carbohydrate that reaches the colon undigested and can therefore fuel the colonic microbiome. If they fuel beneficial bacteria, they are also prebiotics.
Key terms High Density Lipoprotein (HDL):
is a type of lipoprotein in blood that binds lipids like cholesterol and transports them away. The HDL particle is sometimes called ‘good cholesterol’.
Key terms Lean body mass (LBM):
Composition of the body minus fat mass.
Key terms Low Density Lipoprotein (LDL):
is another lipoprotein transport system but these transport cholesterol to the cardiovascular disease. Commonly known as ‘bad cholesterol’.
Key terms Macronutrients:
Nutrients that make up the bulk of diet: fats, carbohydrates, and proteins. They provide the basic needs of the human metabolism: energy and amino acids.
Key terms Microbiome:
The collection of microbes that live in and on our bodies. These number in the trillions, way in excess of our own body cell number, and can be bacteria, fungi or viruses.
Key terms Micronutrients:
Nutrients required by the body in small quantities. These are further subdivided into vitamins, minerals, and trace elements.
Key terms Monounsaturated fatty acids (MUFA’s):
Fatty acids with a single double bond in their chemical structure. High levels found in olive oil.
Key terms Nutritional immunity:
The process whereby micronutrients are moved into cells in the early stages of an infection, reducing their availability to pathogens.
Key terms Polyunsaturated fatty acids (PUFA’s):
Fatty acids with multiple double bonds in their chemical structure. Ω 3 and Ω 6 are PUFA’s.
Key terms Prebiotics:
Oligosaccharides that reach the colon undigested and provide a food source to colonies of potentially beneficial bacteria. Examples are inulin, fructo and galacto - oligosaccharides and beans that contain large quantities of stachyose.
Key terms Probiotics:
Foodstuffs, such as yoghurt, that containlivemicroorganisms. The microorganisms (colloquially known as ‘good’ bacteria) travel live into the GIT, colonise it and thereby restore an improved microbial balance. Common probiotics include lactobacilli, bifidobacteria, streptococci, and some yeasts and moulds.
Key terms Resting metabolic rate:
Similar to BMR but reflects measurement when the strict conditions for BMR measurement are not controlled.
Key terms Sepsis:
is a life-threatening organ dysfunction caused by a dysregulated host-response to infection.