Nutrition and Diet Therapy - Basic Concepts and Classification of Nutrients

Comprehensive practice flashcards covering basic nutrition concepts, diet therapy terms, and the classification/functions of nutrients based on the lecture notes.

Nutrition

The science of food, nutrients, and other substances therein, focusing on their action, interaction, and balance in relation to health and disease, as well as the process by which an organism ingests, absorbs, transports, utilizes, and excretes food substances.

Food

Any substance that, when ingested, nourishes the body by building and repairing tissues, supplying heat and energy, and regulating body processes.

Nutrients

Organic and inorganic substances found in foods that are required by the body for energy, growth, maintenance, and repair.

Six Essential Nutrients

The categories of substances required in human nutrition: carbohydrates, proteins, fats, vitamins, minerals, and water.

Nutritive Value

The nutrient content of a specified amount of food.

Nutritional Status (Nutriture)

The condition of an individual's health as influenced by the utilization of essential nutrients, characterized as good, fair, or poor.

Health

A state of complete physical, mental, and social well-being and not merely the absence of disease or infirmity, according to the WHO.

Nutritional Care

The application of the science and art of human nutrition to help people select and obtain food for the purpose of nourishing the body throughout the life cycle.

Malnutrition

A dietary condition caused by a deficiency, excess, or imbalance of one or more essential nutrients in the diet.

Undernutrition

A state of insufficient supply of essential nutrients which may be primary (lack of food) or secondary (metabolism error or drug interaction).

Overnutrition

An excessive intake of one or more nutrients that creates stress in bodily functions.

Diet

Everything an individual eats and drinks each day, including normal, hostel, or modified therapeutic diets.

Diet Therapy

A method of eating prescribed by a physician to improve health or modify an existing dietary lifestyle.

Dynamic Equilibrium

A state where nutrients in the body are in metabolic balance; for example, maintaining blood glucose levels within a relatively stable range despite constant usage and replacement.

Macronutrients

Nutrients needed by the body in larger amounts, specifically carbohydrates, proteins, and fats.

Micronutrients

Nutrients the body needs in smaller amounts, commonly referred to as vitamins and minerals.

Carbohydrates (CHO)

Organic compounds containing carbon, hydrogen, and oxygen that contribute at least $50\%$ of total energy needs.

Monosaccharides

The smallest carbohydrates containing just one sugar unit, including glucose, fructose, and galactose.

Glucose

Also called blood sugar, it is the main energy source for the central nervous system and brain, and requires insulin to be taken into cells.

Fructose

The sweetest of all sugars, also known as levulose, found in fruits and honey.

Galactose

A monosaccharide rarely found alone in nature but part of the disaccharide lactose found in milk.

Disaccharides

Double sugars formed when two monosaccharides are joined by a glycosidic linkage, such as sucrose, maltose, and lactose.

Sucrose

A disaccharide composed of one glucose molecule bonded to one fructose molecule; chemically identical to table sugar.

Maltose

A disaccharide composed of two glucose molecules, produced when plant starch is broken down or cereal grains germinate.

Lactose

Known as "milk sugar," it is composed of glucose and galactose and is found in dairy products.

Polysaccharides

Complex carbohydrates containing many sugars, such as starch, glycogen, and fiber.

Starch

The storage form of carbohydrate in plants, found in grains, legumes, and certain vegetables.

Glycogen

The storage form of carbohydrate in animals and humans, stored in the liver and skeletal muscle for quick energy release.

Fiber

Also known as roughage or residue, these are the indigestible parts of plants that consist of strings of simple sugars.

Soluble Dietary Fibers

Fibers like pectin that dissolve in fluids, thicken substances, and can retard gastric emptying.

Insoluble Dietary Fibers

Fibers such as cellulose and hemicellulose that do not dissolve in fluids and provide structure to plants.

Protein Sparer

The function of carbohydrates to provide energy first, thereby saving proteins for their specific body-building functions.

Glucuronic Acid

A glucose metabolite in the liver that combines with chemical and bacterial toxins to detoxify them for elimination.

Protein-Energy Malnutrition (PEM)

A spectrum of biological disorders caused by a deficiency of total energy, including conditions like Marasmus and Kwashiorkor.

Hypoglycemia

Low blood sugar, usually defined as levels less than $70\,\text{mg/dL}$, which can cause shakiness, sweating, and confusion.

Obesity

A disease of positive energy balance characterized by an excess accumulation of body fat or adipose tissue.

Dental Caries

Cavities formed by bacteria metabolizing carbohydrates and producing acid that destroys tooth enamel.

Galactosemia

An inherited disease where the transformation of galactose to glucose is blocked, leading to toxic levels of galactose.

Ketosis

The abnormal accumulation of ketones in the body due to excessive fat breakdown when carbohydrates are deficient.

Protein

Organic compounds containing carbon, hydrogen, oxygen, and nitrogen ($\text{CHON}$) composed of chains of alpha-amino acids.

Essential Amino Acids

The nine amino acids that cannot be made by the body and must be obtained from food.

Simple Proteins

Proteins that yield only amino acids upon hydrolysis, such as albumins, globulins, and glutelins.

Conjugated Proteins

Simple proteins combined with non-protein prosthetic groups, such as nucleoproteins or hemoglobins.

Marasmus

A disease caused by severe deficiency of both protein and calories, resulting in significant weight loss and dehydration in infants.

Kwashiorkor

A protein deficiency disease occurring in children whose diets contain mostly carbohydrate calories, characterized by a puffy abdomen and edema.

Phenylketonuria (PKU)

A genetic disorder characterized by the inability to break down excess phenylalanine, leading to potentially toxic levels in the body.

Sickle Cell Disease

A genetic protein disorder where abnormal hemoglobin causes red blood cells to become curved and clog small vessels.

Lipids

Organic compounds insoluble in water but soluble in fat solvents, stored as energy reserves and used in cell membranes.

Saturated Fatty Acids

Fatty acids where each carbon atom has two hydrogens attached to it, and no double bonds exist.

Unsaturated Fatty Acids

Fatty acids where at least one hydrogen atom is missing, requiring a double bond between carbon atoms.

Adipose Tissue

The storage depot of body fat; one pound of this tissue can produce $3500\,\text{kcal}$ of energy.

Linoleic and Linolenic Acid

Essential fatty acids necessary for making compounds like prostaglandins that regulate blood pressure and clotting.

Visible Fats

Specific fat sources identified easily in the diet, such as butter, margarine, and cooking oils.

Invisible Fats

Fats contained within foods that are not immediately obvious, such as those in avocados, egg yolks, and milk.

Vitamins

Potent organic compounds essential in minute amounts for regulatory functions and the maintenance of life, which do not provide energy themselves.

Avitaminosis

A condition resulting from a complete lack of a specific vitamin.

Hypervitaminosis

A condition caused by the excessive ingestion of one or more vitamins.

Fat-Soluble Vitamins

Vitamins $A$, $D$, $E$, and $K$ which can be stored in the body and generally have provitamins.

Water-Soluble Vitamins

Vitamin $C$ and the $B$-complex vitamins, which must be supplied daily as they are not stored and are excreted in urine.

Vitamin A (Retinol)

Exists in active preformed (retinol) and inactive plant (carotenoids) forms; essential for bone growth and cell membrane stability.

Vitamin D

The "sunshine vitamin" or anti-rachitic factor, existing as $D_2$ and $D_3$, essential for Calcium and Phosphorus metabolism.

Vitamin E (Tocopherols)

An antisterility vitamin with antioxidant properties that protects cell structure.

Vitamin K

The antihemorrhagic factor essential for proper blood clotting and phosphorylation.

Vitamin C (Ascorbic Acid)

A "fresh food" vitamin and antioxidant essential for cellular units and iron metabolism; deficiency lead to scurvy.

Vitamin B1 (Thiamine)

An antineuritic factor essential for carbohydrate metabolism; deficiency causes Beriberi (wet or dry).

Vitamin B2 (Riboflavin)

A vitamin containing ribose and yellow pigment, essential for nutrient metabolism and tissue maintenance; deficiency causes Cheilosis.

Vitamin B3 (Niacin)

The antipelagra factor that helps convert carbohydrates to glucose and make hormones; deficiency causes Pellagra (the three $D$s).

Vitamin B12 (Cobalamins)

A group of vitamins containing cobalt essential for DNA/RNA synthesis; deficiency can cause Pernicious Anemia.

Folacin (Folic Acid)

A vitamin required for amino acid synthesis; deficiency can cause Megaloblastic anemia.

Biotin

A member of the $B$ vitamin complex that assists in the transfer of carbon dioxide during metabolism.

Minerals

Inorganic compounds comprising $4-6\%$ of total body weight, essential as catalysts and structural components.

Calcium (Ca)

Major mineral for the maintenance of bones and teeth, blood clotting, and heart function.

Sodium (Na)

The major cation in extracellular fluid that regulates fluid and acid-base balance.

Potassium (K)

The primary intracellular electrolyte that maintains fluid balance and promotes muscle contraction.

Iron (Fe)

A trace mineral essential for hemoglobin formation; deficiency leads to anemia characterized by fatigue and pale skin.

Iodine (I)

A trace mineral required for the formation of thyroid hormones; deficiency leads to goiter or hypothyroidism.

Fluoride

A trace mineral that increases resistance to tooth decay.

Hard Water

Water containing high amounts of minerals such as calcium and magnesium.

Soft Water

Water filtered to replace some minerals with sodium.

Thirst

A dryness in the mouth controlled by the hypothalamus that stimulates the desire to drink when water levels are low.

Dysphagia

Difficulty in swallowing, which can be caused by painful inflammation or esophageal structures, preventing adequate nourishment.