UMD NSFC100

Nutrition

the science of food and the nutrients they contain

Scientific Method

a systematic approach to conducting scientific research, involving formulating hypotheses, testing them, evaluating results, and comparing them to the original hypothesis

Types of studies

case studies, epidemiological studies, laboratory studies, and intervention studies

Food labeling

provides information about nutrients in food and helps make informed choices

% Daily Value

indicates how much of a specific nutrient one serving of food contains compared to daily nutrient recommendations

Types of Claims

nutrient content claims, health claims, and structure/function claims

Hunger

regulated by the hypothalamus and influenced by hormones and brain chemicals

Composition of Meals

dietary fiber and water are more filling, and the balance of macronutrients can affect hunger

Influences on Food Choices

natural environment, technology, income, demand, population size, and food deserts

Nutrients

components of food used for the body's functioning

Classes of Nutrients

proteins, carbohydrates, lipids, vitamins, minerals, and water

Nutrient Density

a measure of how many nutrients a food provides relative to its calorie content

Characteristics of a Nutritious Diet

adequacy, moderation, variety, balance, and calorie control

Obesity BMI

a body mass index (BMI) of 30 or higher

Diet Evaluation

dietary reference intakes (DRI's), including RDA, EER, EAR, AI, and UL

Dietary Guidelines for Americans

science-based advice for healthy eating patterns

Macronutrient Breakdown of Diet

recommended proportions of carbohydrates, proteins, and fats in the diet

Serving vs Portion

serving refers to a unit of measure, while portion refers to the amount of food actually consumed

Nutrient Density

a measure of the amount of nutrients per calorie in a food

Digestion, Absorption, and Metabolism

the processes by which food is broken down, nutrients are absorbed, and the body uses and stores energy

The Cell

the basic unit of life, consisting of a nucleus, plasma membrane, cytoplasm, and organelles

Different Body Systems

integumentary system, cardiovascular system, lymphatic system, skeletal and muscular systems, and nervous system

Sensation, interpretation, integration

Concerned with the processing of sensory information.

Endocrine system

Consists of the hypothalamus and glands such as the pituitary gland, thyroid, adrenal, and pancreas. Secretes hormones that regulate body activities.

Digestive system

Includes the mouth, esophagus, stomach, intestines, and associated organs. Responsible for breaking down and absorbing food, as well as excreting waste.

Urinary system

Composed of the kidneys, bladder, and ducts. Regulates body water and salt balance, excretes waste as urine, and maintains acid-base balance of blood.

Respiratory system

Consists of the lungs and respiratory passages. Responsible for taking in oxygen and excreting carbon dioxide and other waste products.

Reproductive system

Includes the gonads and genitals. Involved in the production of offspring.

Immune system

Divided into nonspecific defense (innate immune system) and specific defense (adaptive immune system). Main cells of the immune system are lymphocytes and phagocytes, which produce antibodies.

Digestion

The process of breaking down food into absorbable nutrients.

Absorption

The uptake of nutrients by the cells of the small intestine for transport into the blood or lymph.

Metabolism

The body's process of processing nutrients after digestion and absorption.

Gastrointestinal (GI) tract

The digestive tract, including the mouth, esophagus, stomach, and intestines.

Mastication

The process of chewing food, which helps break it down into smaller pieces and mixes it with saliva.

Bolus

The lump of food formed after swallowing.

Chyme

The semi-liquid mixture of food and digestive juices in the stomach.

Small intestine

Approximately 10 feet long and responsible for accepting secretions from the gallbladder/liver and pancreas. Most nutrient absorption occurs here.

Large intestine

Also known as the colon, it absorbs water and minerals and houses bacteria for fermentation.

Digestive enzymes

Biological molecules that increase the rate of chemical reactions in digestion. Examples include protease, lipase, carbohydrase, and sucrase.

Digestive secretions

Substances released during digestion to aid in the breakdown of food. Examples include saliva, gastric juice, pancreatic juice, and bile.

Cell membrane

Holds together cellular contents and regulates the flow of substances into and out of the cell.

Cytoplasm

The fluid material and organelles within a cell.

Mitochondria

Organelles responsible for converting the chemical energy from food into a form of energy that cells can use.

Nucleus

Surrounded by a double membrane, it stores and protects the cell's DNA.

Endoplasmic reticulum

Rough endoplasmic reticulum (RER) is involved in protein synthesis, while smooth endoplasmic reticulum (SER) is involved in lipid synthesis and detoxification.

Golgi complex

Packages proteins and lipids produced in the cell for transport or secretion.

Lysosomes

Contain enzymes for digestion and breakdown of foreign material and worn-out cell components.

Peroxisomes

Contain enzymes that detoxify harmful chemicals, including hydrogen peroxide.

Epithelial tissue

Composed of cells that cover surfaces inside and outside the body.

Connective tissue

Supports and protects the body, stores fat, and produces blood cells.

Muscle tissue

Designed for movement.

Nervous tissue

Found in the brain and spinal cord, responsible for communication and coordination.

Lymphatic system

Removes foreign substances from the blood and aids in fat absorption.

Cardiovascular system

Transports nutrients, waste, gases, and hormones throughout the body.

Peristalsis

Coordinated muscular contractions that propel food along the gastrointestinal tract.

Gut dysbiosis

Imbalance of good and bad microbes in the gut.

Probiotics

Live microorganisms that colonize the large intestine and provide health benefits.

Prebiotics

Forms of dietary fiber that serve as food for probiotics and support gut health.