Fundamentals of Nutrition: Digestion & Carbohydrates - Vocab

Vocabulary flashcards covering key terms and concepts from the lecture notes on holism, digestion, absorption, gut microbiota, GI physiology, and blood sugar regulation.

Holism

Theory that parts of a whole are interconnected; the whole is greater than the sum of its parts.

Holistic Nutrition

Nutrition approach addressing diet, lifestyle, environment, emotions, and overall function of the whole person.

Digestion

Process of breaking down ingested food into smaller, absorbable units via mechanical and chemical means.

Absorption

Transfer of digested nutrients from the gut into the bloodstream for distribution.

Assimilation

Nutrients entering cells to be used for energy, synthesis, or metabolic functions.

Elimination

Removal of metabolic wastes and byproducts from the body via emunctory organs.

Peristalsis

Rhythmic, wave-like muscle contractions that move contents through the digestive tract.

Segmentation

Rhythmic, back-and-forth intestinal contractions that mix contents and enhance contact with enzymes.

MALT

Mucosa-associated lymphatic tissue; gut-associated immune tissue that supports immunity in the GI tract.

Enteric Nervous System

The “second brain” in the GI tract; extensive nerve network that communicates with the brain.

Gut–Brain Axis

Bidirectional communication system between the GI tract and the brain.

Vagus Nerve

Primary nerve pathway linking the gut and brain in the gut–brain axis.

Alimentary Canal

The entire digestive tract from mouth to anus.

Oral Cavity

Mouth area where digestion begins (teeth, saliva, tongue, etc.).

Pharynx

Throat area that passes food, water, and air to the esophagus.

Esophagus

Tube that transports food from the pharynx to the stomach via peristalsis.

Cardiac Sphincter

Lower esophageal sphincter; prevents stomach contents from backing into the esophagus.

Pyloric Sphincter

Sphincter at the stomach’s exit, regulating chyme flow into the small intestine.

Stomach

Muscular sac where chemical (HCl, enzymes) and mechanical digestion occur; highly acidic contents.

Hydrochloric Acid (HCl)

Acid produced by stomach lining; begins protein digestion and pathogen sterilization (low pH).

Pepsinogen/Pepsin

Pepsinogen is the inactive precursor; HCl activates it to pepsin for protein digestion.

Intrinsic Factor

Stomach-produced protein essential for vitamin B12 absorption in the ileum.

Bile

Digestive fluid produced by the liver, stored in the gallbladder; emulsifies fats and aids fat-soluble vitamin absorption.

Gallbladder

Organ that concentrates and stores bile, releasing it into the small intestine as needed.

Liver

Organ that produces bile and plays a central role in metabolism and detoxification.

Pancreas

Gland that secretes bicarbonate and digestive enzymes; also has endocrine roles (insulin/glucagon).

Bicarbonate

Alkaline fluid from the pancreas that neutralizes stomach acid in the small intestine.

Enzymes

Proteins that catalyze chemical reactions; include digestive and metabolic enzymes.

Hormones

Chemical signaling molecules that regulate digestion and other bodily processes.

Gastrin

Hormone that increases stomach acid production and gastric mucosal growth.

Secretin

Hormone that stimulates pancreatic bicarbonate and enzyme secretion; responds to acid in the small intestine.

Cholecystokinin (CCK)

Hormone that stimulates bile and pancreatic enzyme secretion; slows gastric emptying.

Villi

Finger-like projections in the small intestine that increase surface area for absorption.

Microvilli

Even smaller projections on villi, forming the brush border to maximize absorption.

Brush Border Enzymes

Digestive enzymes located on microvilli that finalize nutrient digestion at the intestinal surface.

Enterocytes

Intestinal absorptive cells lining the villi.

Duodenum

First section of the small intestine where chyme mixes with bile and pancreatic enzymes.

Jejunum

Middle portion of the small intestine where most nutrient absorption occurs.

Ileum

Final portion of the small intestine; primary site of vitamin B12 and bile acid reabsorption.

Ileocecal Valve

Sphincter between the ileum and cecum that regulates flow from small to large intestine.

Large Intestine (Colon)

Absorbs water and electrolytes; hosts gut microbiota and forms stool.

Rectum

Last section of the digestive tract, leading to the anus for elimination.

Anus

Opening at the end of the GI tract through which stool is excreted.

Mucosa-Associated Lymphatic Tissue (MALT)

Immune tissue in the gut lining that helps monitor and respond to threats.

Intestinal Permeability

The barrier function of the gut lining; increased permeability can lead to “leaky gut.”

Leaky Gut

Condition where the intestinal barrier is compromised, allowing larger particles into circulation.

Dysbiosis

Imbalance in the gut microbiome, with excessive harmful or fewer beneficial microbes.

Gut Microbiome

Community of microorganisms living in the GI tract that influence digestion, immunity, and metabolism.

Probiotics

Live beneficial bacteria that support gut health when consumed in adequate amounts.

Prebiotics

Non-digestible fibers that feed beneficial gut bacteria (fermentable substrates).

SIBO

Small intestinal bacterial overgrowth; excessive bacteria in the small intestine.

SIFO

Small intestinal fungal overgrowth; excessive fungi in the small intestine.

IBS

Irritable bowel syndrome; a gut-brain related syndrome with varied bowel symptoms.

IBD

Inflammatory bowel diseases; includes ulcerative colitis and Crohn’s disease.

Ulcerative Colitis

IBD affecting the colon’s inner lining with ulcers and inflammation.

Crohn’s Disease

IBD that can affect any part of the GI tract; deep, segmental inflammation.

Celiac Disease

Inherited autoimmune condition triggered by gluten; damages intestinal villi.

Lactose Intolerance

Inability to digest lactose due to low lactase enzyme activity.

Food Sensitivities/Intolerances

Immune-mediated or non-immune reactions to foods resulting in GI or systemic symptoms.

H. pylori

Bacterial infection commonly linked to ulcers and gastritis.

Ulcers

Sores in the GI tract lining caused by factors like low stomach acid, infections, or NSAIDs.

Acid Reflux (GERD)

Backflow of stomach contents into the esophagus; often linked to low stomach acid in this context.

Hypochlorhydria

Low stomach acid production, implicated in poor digestion and reflux.

B12 and Intrinsic Factor

B12 absorption requires intrinsic factor in the ileum for efficient uptake.

Transit Time

The total time from ingestion to elimination; typically 12–24 hours for a full passage.

Bristol Stool Chart

A system classifying stool form; types 3–4 are generally ideal.

Glycemic Index (GI)

A measure of how quickly a carbohydrate-containing food raises blood glucose.

Glycemic Load (GL)

GI adjusted for the amount of carbohydrate in a serving; reflects overall glucose response.

Net Carbs

Digestible carbohydrates = total carbohydrates minus fiber (and sugar alcohols in some counts).

Insulin

An anabolic hormone that facilitates cellular uptake of glucose and stores energy as glycogen or fat.

Glucagon

Hormone that raises blood glucose by signaling glycogen breakdown and gluconeogenesis.

Glycogen

Stored form of glucose in liver and muscles.

Glycogenesis

Formation of glycogen from glucose for storage.

Glycogenolysis

Breakdown of glycogen into glucose to raise blood glucose.

Gluconeogenesis

Creation of glucose from non-carbohydrate sources during fasting or stress.

Lipolysis

Breakdown of fats into fatty acids and glycerol for energy.

Lipogenesis

Synthesis of fatty acids and triglycerides from carbohydrates or fats.

Glucose

Monosaccharide; primary energy source for cells; absorbed directly into bloodstream.

Fructose

Monosaccharide found in fruit; processed forms (e.g., high-fructose corn syrup) can be problematic in excess.

Galactose

Monosaccharide derived from lactose; converted to glucose in the liver.

Disaccharides

Two-molecule carbohydrates (e.g., lactose, sucrose, maltose) that require enzymatic breakdown.

Monosaccharides

Single-sugar units (glucose, fructose, galactose) absorbed into the bloodstream.

Polysaccharides

Carbohydrates made of many sugar units (starch, glycogen, fiber).

Amylose

Linear component of starch with alpha bonds; digestible by humans.

Amylopectin

Branched component of starch with alpha bonds; digestible by humans.

Cellulose

Indigestible fiber in plants; beta-bonded polysaccharide not broken by human enzymes.

Glycemic Index (GI) Low/Med/High

Classification of foods based on how they affect blood glucose levels.

Glycemic Load (GL)

Glycemic impact of a portion of food, accounting for available carbohydrate.

Beta Bonds vs Alpha Bonds

Alpha bonds are digestible in starch; beta bonds form non-digestible fibers.

Resistant Starch

Starch that resists digestion in the small intestine and feeds gut bacteria.

Vitamin C

Water-soluble vitamin; antioxidant; supports collagen, immune defense, detoxification; high-dose protocols may be used under guidance.

Vitamin A

Fat-soluble vitamin essential for mucous membranes and vision; excessive intake can be toxic.

Vitamin E

Fat-soluble antioxidant; supports cell membranes and gut healing; stored in fats.

Zinc

Mineral essential for HCl production, immune function, and tissue healing; may require food when dosing.

Magnesium

Mineral important for muscle relaxation and motility; often deficient; supports digestion and stress relaxation.

EPA/DHA (Omega-3s)

Fatty acids from fish oil with anti-inflammatory properties and roles in cell membranes.

L-Glutamine

Amino acid that supports gut mucosal healing and barrier integrity.

Demulcents

Herbal/supportive agents that soothe irritated mucous membranes (e.g., aloe, slippery elm).

Licorice DGL

Deglycyrrhizinated licorice; soothing to the gut lining without blood-pressure risk when used appropriately.

Probiotics (strains)

Specific live microbes that help rebalance gut flora; effectiveness depends on strains and context.