Integrative and Functional Nutrition Vocabulary

Vocabulary terms and definitions compiled from Modules 1 and 2 of Integrative and Functional Nutrition.

Autoantibodies

An antibody made against substances formed by a person's own body. Autoantibodies can directly destroy cells that have the substances on them or can make it easier for other white blood cells to destroy them, causing certain autoimmune diseases.

Autoimmunity

The presence of B lymphocyte-produced antibodies and T lymphocytes directed against normal components of a person (autoantigens), representing the process of developing a negative immune response/attack against one's own tissue (e.g., joints, brain, pancreas).

Beta-glucuronidase

An enzyme that breaks the tight bond between glucuronic acid and toxins or steroid hormones (such as estrogens) in the intestines. High levels allow previously bound toxins to re-enter the enterohepatic circulatory system, causing imbalances.

Biochemical Individuality

The unique chemical, physiological, and metabolic makeup of an individual arising from interactions of genetic makeup with diet, microbiome, environment, and continuous inputs (lifestyle, activity, toxins, beliefs, medications). It shapes disease risk, nutritional needs, and metabolic responses, requiring personalized care to maintain optimal health and prevent long-term degenerative disease.

Biological response modifier (BRM)

A dietary component or nutrient that augments, enhances, or modulates the immune system and other physiological responses in the body. They can be macronutrients, micronutrients, or bioactive food components (e.g., polysaccharides, polyphenols, probiotics).

Biomarker

A substance used as an indicator of a biological state that is objectively measured and evaluated as an indicator of normal biological processes, pathogenic processes, or pharmacologic responses to a therapeutic intervention.

Biotransformation

The chemical modification(s) of a compound (nutrients, amino acids, toxins, heavy metals, drugs) made by an organism. It renders nonpolar compounds polar so that they can be excreted rather than reabsorbed in renal tubules.

Cell danger response

An evolutionarily conserved metabolic response that protects cells and hosts from chemical, physical, or biological threats that exceed cellular homeostatic capacity. Coordinated primarily by mitochondria, which monitor and respond to environmental conditions within and around the cell.

Cephalic phase

The initial stage of gastric secretion triggered by the sight, smell, or thought of food before it enters the stomach, initiating digestive salivary and gastric secretions via the autonomic nervous system.

Chronic disease

A food, lifestyle (environment), and genetics influenced phenomenon that must be approached with a science-based, multidimensional care process.

Complementary and Alternative Medicine (CAM)

A group of diverse medical and healthcare systems and practices that can be used together or in place of conventional medicine.

COMT

Catechol-O-methyltransferase; a magnesium-dependent gene/protein enzyme that converts 4 hydroxy estradiol/estrone to 4 methoxy estradiol/estrone to reduce DNA damage and estrogen-based cancer risk. It is also responsible for degrading catecholamine neurotransmitters (dopamine, epinephrine, and norepinephrine).

Cytochrome P450s (CYP 450)

A large and diverse group of enzymes located in the inner membrane of mitochondria or the endoplasmic reticulum that catalyze the oxidation of organic substances (lipids, steroidal hormones, drugs, xenobiotics), playing a critical role in detoxification.

Cytokine

A group of small, short-lived signaling proteins released by cells that act as chemical messengers to regulate immunity, inflammation, and blood cell production during immune responses and tissue repair.

Detoxification

The general process of removing harmful substances from the body.

Dysbiosis

A condition occurring when the normal symbiosis between gut flora and the host is disturbed, allowing organisms of low intrinsic virulence to promote illness; distinct from acute gastrointestinal infection.

Endotoxin

A toxic, heat-stable structural component found in the outer membrane of Gram-negative bacteria (such as E. coli and Salmonella).

Enteric Nervous System

A vast, mesh-like network of neurons embedded in the walls of the gastrointestinal tract, often called the "second brain", which independently controls digestive motility, blood flow, and secretions without requiring input from the brain or spinal cord.

Enterohepatic circulation

The continuous recycling loop of substances (bile acids, bilirubin, certain drugs) between the liver and the digestive tract, allowing the body to conserve compounds and extend their active duration.

Epigenetics

DNA modifications ("Epi" meaning over, above, around the genes) that do NOT change the DNA sequence but affect gene expression by turning genes on or off (e.g., DNA methylation).

Estrogen Metabolites

Compounds created when estrone and estradiol are irreversibly hydroxylated at the 2-, 4-, or 16-position of the steroid ring during estrogen breakdown.

Eustress

A positive form of stress that motivates, energizes & enhances performance.

Evidence-Based Practice

The conscientious, explicit, and judicious use of current best evidence in making decisions about individual patient care, integrating clinical expertise with external research evidence.

Exposome

Measure of all exposures in a lifetime and their impact on health.

Exposomics

The comprehensive study of the "exposome"—the totality of environmental exposures (chemical, physical, biological, social, and lifestyle) a person experiences from conception to death.

Functional medicine

Originally called nutritional medicine and codified by Jeffrey Bland, PhD, functional medicine uses a systems biology approach to investigate root causes of chronic disease and underlying system imbalances.

Global Burden of Disease

Describes mortality and morbidity from major diseases, injuries, and risk factors to health at global, national, and regional levels.

Gut-Associated Lymphoid Tissue (GALT)

A primary defense barrier of the immune system located throughout the GI tract that identifies harmful pathogens and toxins while tolerating beneficial gut bacteria and dietary nutrients.

HANDS ON

An IFNA nutrition assessment heuristic that includes: History and Lifestyle, Anthropometrics and Vitals, Nutrition Physical, Diet and Food Habits, Supporting Clinical Data, and Ongoing nutrition monitoring and evaluation.

Health (WHO)

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

Healthy aging (WHO)

The process of developing and maintaining the functional ability that enables well-being in older age.

Hormesis

A biological phenomenon where low-dose exposure to an otherwise toxic, harmful, or stressful agent triggers an adaptive, beneficial response in the body.

Human Metabolome Database (HMDB)

An extensive searchable library of metabolites that can be filtered by interest (e.g., food, microbial, toxin/pollutant, drug, etc.), such as the microbial metabolite butyric acid.

IFN Care Plan

Entails 5 key areas for providing personalized recommendations including Food, Labs, Lifestyle, Supplements, Resources & Referrals.

Immunosenescence

Alterations in immune function that occur with aging, characterized by a decline in immunocompetence leading to increased susceptibility to malignancy, infections, and autoimmune disorders.

Inflammaging

A concept that describes immune changes in response to lifelong proinflammatory processes.

Integrative and Functional Medicine Nutrition Therapy (IFMNT)

An application of medical nutrition therapy incorporating integrative and functional medicine principles with conventional (mainstream/Western) nutrition practice.

Integrative and Functional Nutrition

The advanced practice of delivering personalized nutrition care aimed at promoting optimal health while preventing diet- and lifestyle-related diseases through root-cause-focused care.

Integrative Medicine

Healing-oriented medicine that combines conventional medicine and Complementary and Alternative Medicine (CAM), considering the whole person (body, mind, spirit) and lifestyle.

Interactome

In molecular biology, the whole set of molecular interactions in a particular cell.

Lifestyle Medicine

Employs lifestyle interventions including nutrition, physical activity, stress management, and restorative sleep to reduce risk and treat lifestyle-related chronic diseases.

Lipopolysaccharide (LPS)

A type of endotoxin and major structural glycolipid in the outer membrane of Gram-negative bacteria (e.g., E. coli, Salmonella). It mediates host-microbe interactions, acts as a potent stimulator of the innate immune system, and shifts toward inflammatory variants in dysbiosis.

Long Tail of Biology

A term coined by systems biology experts describing aging and chronic disease susceptibility caused by cumulative erosion of physiological resilience from countless small-effect perturbations across genetics, microbiome, exposures, and lifestyle.

Metabolic detoxification

The body's natural two-phase process of removing foreign substances from the body; synonymous with biotransformation.

Micronutrient

Nutrients needed by the body in smaller amounts (vitamins, minerals, phytonutrients) that often act as cofactors modulating enzyme activity.

Mitochondria

The organelle often referred to as the "powerhouse" of the cell where the most ATP (energy) is produced; cellular damage to mitochondria may lead to fatigue disorders.

Molecular Mimicry

A mechanism where a foreign antigen shares sequence or structural similarities with self-antigens, serving as a primary pathway by which infectious or chemical agents induce autoimmunity.

Multiple morbidity

The coexistence of two or more chronic medical conditions (physical or mental) in one individual, where no single condition is necessarily central.

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS)

Also known as Systemic Exertion Intolerance Disease (SEID); a chronic neuroimmune disease characterized by exhaustion, cognitive dysfunction ("brain fog"), and post-exertional malaise (PEM).

My Symptom Questionnaire (MySQ)

An IFNA clinical tool that explores both signs and symptoms that a patient is experiencing.

N of 1

Single subject clinical trials that consider an individual patient as the sole unit of observation; in clinical practice, refers to a single patient.

Non-Communicable Diseases (NCD)

Another term for chronic diseases.

Nutrient sensing

Mechanism by which cells respond to nutrient concentration changes or homeostatic disturbances by activating signaling pathways that modulate gene expression.

Occludin

A structural protein found in cell tight junctions that acts as a gatekeeper controlling paracellular transport and maintaining tissue barrier integrity.

Omics

Biological disciplines ending in the suffix -omics, such as genomics, proteomics, metabolomics, metagenomics, phenomics, and transcriptomics.

One Health

The concept that human health is connected to the health of animals and our shared environment.

Orthomolecular Medicine

An approach coined by Linus Pauling aiming to maintain health and treat disease using optimal concentrations of natural substances (vitamins, minerals, amino acids, antioxidants), often involving high-dose megavitamin therapy.

P4 Medicine/Healthcare

A systems approach outlined by Dr. Leroy Hood characterized by four keys: Predictive (genetics/omics), Preventative, Personalized, and Participatory.

Personalized Nutrition

Individual-specific advice using routinely collected data, anthropometrics, labs, diet history, activity, and genetics to guide dietary behavior change.

Phenotype

An ensemble of physical, biochemical, physiological, and behavioral characteristics.

Polyphenols

A major subgroup of phytonutrients with over 8,000 identified types known for antioxidant and anti-inflammatory properties, categorized into classes like flavonoids and phenolic acids.

Precision Nutrition

Tailored nutritional recommendations relying on multi-omics, big data, and AI/machine learning to decipher complex interactions among diet, genes, microbiome, metabolism, and environment.

Proteostasis

Protein homeostasis; the cellular process regulating protein synthesis, folding, trafficking, and degradation to maintain a functional proteome and prevent harmful protein accumulations.

Qigong

Meditative movement therapy that includes breath work, meditation, and gentle movement.

Reactive Oxygen Species (ROS)

Unstable, oxygen-containing molecules highly reactive in cells; natural metabolic byproducts that can damage DNA, proteins, and lipids if accumulated in excess.

STAIN

An IFNA heuristic for root cause analysis covering Stress, Toxins, Adverse Food Reactions, Infections, and Nutritional Imbalances.

Steroidal hormones

Cholesterol-derived hormones secreted by the adrenal cortex, testes, ovaries, and placenta, divided into corticosteroids and sex steroids (testosterone, progesterone, estrogens).

Steroidogenic pathways

The biochemical pathways involved in the synthesis of steroid hormones from cholesterol (steroidogenesis).

System imbalances

Core clinical imbalances within interrelated biological systems resulting from environmental inputs; the underlying cause of disease and dysfunction.

Systems biology

The study of mechanisms underlying complex biological processes as integrated systems of many interacting compounds.

Telomere

A region of repetitive DNA at the end of a linear chromosome (analogous to plastic tips on shoelaces) that caps and protects chromosomes from degrading, fraying, or fusing.

Tight Junctions

Specialized multiprotein complexes forming a seal between adjacent epithelial and endothelial cells, acting as a selective physical barrier against paracellular leakage.

Triage Theory

Theory proposed by Dr. Bruce Ames stating that during micronutrient shortages, the body prioritizes immediate survival functions (metabolism, reproduction) over long-term protection (DNA repair, disease prevention).

Ultra-Processed Foods (UPFs)

Formulations of ingredients resulting from industrial processes containing non-culinary food substances and cosmetic additives (e.g., high fructose corn syrup, hydrogenated oils, emulsifiers) to create hyper-palatable products.

Vital Capacity

A physiological state resulting from interactions between energy/metabolism, neuromuscular function, and immune/stress response systems (WHO working definition).

Whole Person Health

An approach considering biological, psychological, social, spiritual, and ecological dimensions of a patient in an integrated, holistic fashion.

Xenobiotic

Any chemical substance found within an organism that is foreign or not naturally produced by it, including dietary components, artificial additives, industrial chemicals, and drugs.

Zonulin

A protein that regulates intestinal lining permeability by controlling tight junctions; elevated levels correlate with intestinal barrier disruption ("leaky gut").