Food choices and human health

Health

The state of being free from illness or injury; profoundly affected by nutrition.

Malnutrition

Condition caused by too much OR too little of nutrients. Includes both undernutrition and overnutrition.

Undernutrition

A form of malnutrition caused by deficiencies of energy or essential nutrients.

Overnutrition

A form of malnutrition caused by consuming too much energy or excess amounts of specific nutrients.

Chronic Diseases

Diseases that develop over time and cannot be prevented by diet alone. e.g., Heart disease, diabetes, some cancers.

Inherited Disease

A condition passed from parent to child via genes. e.g., Hemophilia, sickle cell anemia.

Acquired Disease

A condition associated with infections, lifestyle behaviors, or diet. e.g., Heart attack, diabetes, vitamin deficiencies.

Lifestyle Factors influencing health

Tobacco & alcohol use, Physical Activity, Sleep, Stress, Environmental Factors, Substance Abuse.

Nutritional Genomics

Integration of nutrition, genomic science, and molecular biology. Studies how nutrients affect genes and how genes affect nutrients.

Gram (g)

A unit of weight. Used to weigh foods or nutrients.

Calorie (kcal)

Amount of heat energy needed to raise the temperature of 1 kg of water by 1 degree Celsius. Measures food energy.

Macronutrients

Nutrients needed in large amounts that provide energy: Carbohydrates, Fats, Proteins.

Micronutrients

Nutrients needed in small amounts that act as regulators: Vitamins and Minerals.

Carbohydrates

Provide 4 kcal per gram. An energy-yielding macronutrient.

Fats (Lipids)

Provide 9 kcal per gram. An energy-yielding macronutrient.

Proteins

Provide 4 kcal per gram. An energy-yielding macronutrient.

Water

A non-caloric, essential nutrient. Vital for all life processes.

Essential Nutrient

A nutrient the body cannot make for itself; must be obtained from food to prevent deficiencies.

Non-Essential Nutrient

A nutrient the body can make in sufficient amounts, even if it is still needed for health.

Organic Nutrients

Nutrients that contain carbon-hydrogen bonds (e.g., carbohydrates, lipids, proteins, vitamins).

Inorganic Nutrients

Nutrients that do not contain carbon-hydrogen bonds (e.g., minerals, water).

Elemental Diets

Diets composed of purified ingredients meant to supply all essential nutrients. Used for critically ill patients.

Whole Foods

Basic, minimally processed foods that form the foundation of a nutritious diet. e.g., fruits, vegetables, whole grains.

Nutrient Density

The amount of nutrients a food provides relative to the calories it contains. Key principle for choosing healthy foods.

Challenges of Choosing Foods

Barriers include: lack of time, cost, cravings, competing priorities, cultural identity (foodways).

Foodways

The sum of a culture’s habits, customs, beliefs, and preferences concerning food.

Ethnic Food

Foods associated with a particular culture within a population.

Stages of Change (Transtheoretical Model)

Precontemplation, Contemplation, Preparation, Action, Maintenance, Adoption/Moving On.

Precontemplation Stage

Not considering a change. Unaware or unconcerned about the problem.

Contemplation Stage

Thinking about making a change. Weighing the pros and cons.

Preparation Stage

Planning for change. Taking small steps and setting a start date.

Action Stage

Actively modifying behavior and environment.

Maintenance Stage

Sustaining the new behavior over time; working to prevent relapse.

Science of Nutrition

An ever-evolving field of knowledge that uses the scientific method.

Case Study

Involves studying an individual. Often used to generate hypotheses.

Epidemiological Study

Used to determine correlations or relationships within populations. Cannot prove causation.

Laboratory Study

Designed to determine causes and effects, often in controlled settings or with animals.

Intervention Trial

Designed to evaluate a treatment and observe outcomes. e.g., clinical trials.

Correlation

A relationship or connection between two factors. Does not imply that one causes the other.

Causality

When one factor demonstrably causes an effect. Established using criteria like Hill's.

Hill's Criteria for Causality

Strength of association, Consistency, Temporality, Plausibility, Biological gradient (dose-response).

Control Group

The group in an experiment that does not receive the treatment. Serves as a baseline for comparison.

Placebo

A fake treatment (e.g., sugar pill) given to the control group.

Placebo Effect

A healing effect that arises from the patient's belief in the treatment, not the treatment itself.

Blind Experiment

An experiment where the subjects do not know if they are in the experimental or control group.

Double-Blind Experiment

An experiment where neither the subjects nor the researchers know who is in the experimental or control group.

Anatomy of a Research Paper

Sections: Abstract, Introduction, Methods, Results, Discussion, Conclusions, References.

Registered Dietitian (RD)

A nutrition expert with specific clinical training and licensure. All RDs are nutritionists.

Nutritionist

A broader title; not all nutritionists are RDs. May lack standardized training and licensure.

Reliable Nutrition Information Sources

Academy of Nutrition and Dietetics (eatright.org), American Heart Association, PubMed (pubmed.gov).

Evaluating a Website

Check: Who runs it? Credentials? Selling something? Updated? Links to reliable sources?

Cardiovascular Diseases

The number one killer; an example of a chronic disease with strong diet and lifestyle connections.

Phytochemicals

Biologically active compounds in plants ("non-nutrients") that have health benefits.

Bomb Calorimeter

A device used to measure the energy (calorie) content of foods by burning them.

Primary Reason Food > Supplements

Food provides beneficial non-nutrients, GI stimulation, and physical/psychological/social comfort.

Main Driver of Food Choices

Many factors other than nutrition, including taste, cost, convenience, and culture, are primary drivers.

Temporality (Hill's Criterion)

The cause must precede the effect. A fundamental requirement for establishing causality.

Realistic Goals (Behavior Change)

Setting achievable, specific goals is crucial for success and is dependent on the Stage of Change.

Peer-Reviewed Journal Article

The most reliable source of scientific information, as it has been critiqued by experts before publication.