amino acids: Simple molecules that occur naturally in plant and animal tissues and that are the basic building blocks of proteins.
artificial sweetener: A chemical substance that has a sweet taste but few or no calories. People and food manufacturers add artificial sweeteners to foods and drinks to give them a sweeter taste. Many different artificial sweeteners exist. They include saccharin, sucralose and aspartame, among others.
aspartame: An artificial sugar first created in 1965, and initially sold as NutraSweet. This chemical tastes sweet but has very few calories compared to real sugar.
biology: The study of living things. The scientists who study them are known as biologists.
calorie: The amount of energy needed to raise the temperature of 1 gram of water by 1 degree Celsius. It is typically used as a measurement of the energy contained in some defined amount of food. The exception: when referring to the energy in food, the convention is to call a kilocalorie, or 1,000 of these calories, a “calorie.” Here, a food calorie is the amount of energy needed to raise 1 kilogram of water 1 degree C.
cell: (in biology) The smallest structural and functional unit of an organism. Typically too small to see with the unaided eye, it consists of a watery fluid surrounded by a membrane or wall. Depending on their size, animals are made of anywhere from thousands to trillions of cells. Most organisms, such as yeasts, molds, bacteria and some algae, are composed of only one cell.
chemical: A substance formed from two or more atoms that unite (bond) in a fixed proportion and structure. For example, water is a chemical made when two hydrogen atoms bond to one oxygen atom. Its chemical formula is H2O. Chemical also can be an adjective to describe properties of materials that are the result of various reactions between different compounds.
culture: (n. in social science) The sum total of typical behaviors and social practices of a related group of people (such as a tribe or nation). Their culture includes their beliefs, values and the symbols that they accept and/or use. Culture is passed on from generation to generation through learning. Scientists once thought culture to be exclusive to humans. Now they recognize some other animals show signs of culture as well, including dolphins and primates.
diabetes: A disease where the body either makes too little of the hormone insulin (known as type 1 disease) or ignores the presence of too much insulin when it is present (known as type 2 diabetes).
diet: (n.) The foods and liquids ingested by an animal to provide the nutrition it needs to grow and maintain health. Sometimes this is a specific food-intake plan. (v.) To adopt a specific food-intake plan. People may adopt one for religious or ethical reasons, to address food allergies or to control a disease such as high blood pressure or diabetes. They may also adopt one in an effort to lose weight, although this can be unhealthy if not done under the guidance of a health professional, such as a physician or registered dietician.
digest: (noun: digestion) To break down food into simple compounds that the body can absorb and use for growth. Some sewage-treatment plants harness microbes to digest — or degrade — wastes so that the breakdown products can be recycled for use elsewhere in the environment.
epidemiologist: Like health detectives, these researchers look to link a particular illness to what might have caused it and/or allowed it to spread.
erythritol: A chemical approved as a food addictive. It has a sugary flavor but almost no calories. That’s why food manufacturers use it to help give bulk to branded sweeteners such as Truvia. Normal doses of erythritol are harmless to most people. High doses can cause nausea and upset the stomach.
evolutionary: An adjective that refers to changes that occur within a species over time as it adapts to its environment. Such evolutionary changes usually reflect genetic variation and natural selection, which leave a new type of organism better suited for its environment than its ancestors. The newer type is not necessarily more “advanced,” just better adapted to the conditions in which it developed.
fat: A natural oily or greasy substance occurring in plants and in animal bodies, especially when deposited as a layer under the skin or around certain organs. Fat’s primary role is as an energy reserve. Fat also is a vital nutrient, though it can be harmful if consumed in excessive amounts.
flavor: The particular mix of sensations that help people recognize something that has passed through the mouth. This is based largely on how a food or drink is sensed by cells in the mouth. It also can be influenced, to some extent, by its smell, look or texture. (in physics) One of the three varieties of subatomic particles called neutrinos. The three flavors are called muon neutrinos, electron neutrinos and tau neutrinos. A neutrino can change from one flavor to another over time.
Food and Drug Administration: (or FDA) A part of the U.S. Department of Health and Human Services, FDA is charged with overseeing the safety of many products. For instance, it is responsible for making sure drugs are properly labeled, safe and effective; that cosmetics and food supplements are safe and properly labeled; and that tobacco products are regulated.
fructose: A simple sugar. Along with glucose, fructose makes up half of each molecule of sucrose (also known as table sugar).
fruit: A seed-containing reproductive organ in a plant.
glucose: A simple sugar that is an important energy source in living organisms. As an energy source moving through the bloodstream, it is known as “blood sugar.” It is half of the molecule that makes up table sugar (also known as sucrose).
hormone: (in zoology and medicine) A chemical produced in a gland and then carried in the bloodstream to another part of the body. Hormones control many important body activities, such as growth. Hormones act by triggering or regulating chemical reactions in the body. (in botany) A chemical that serves as a signaling compound that tells cells of a plant when and how to develop, or when to grow old and die.
insulin: A hormone produced in the pancreas (an organ that is part of the digestive system) that helps the body use glucose as fuel.
insulin resistance: A condition where the body begins to ignore the presence of insulin, a hormone needed to help move energy (sugar) from the blood and into cells where it can fuel their activities. Insulin resistance is an early symptom of people at risk of developing type 2 diabetes.
molecule: A group of atoms that represents the smallest possible amount of a chemical compound. Molecules can be made of single types of atoms or of different types. For example, the oxygen in air is made of two bound oxygen atoms (O2). Water is made of two hydrogen atoms and one oxygen atom (H2O).
neuroscientist: Someone who studies the structure or function of the brain and other parts of the nervous system.
obesity: (adj. obese) Extreme overweight. Obesity is associated with a wide range of health problems, including type 2 diabetes and high blood pressure.
organ: (in biology) Various parts of an organism that perform one or more particular functions. For instance, an ovary is an organ that makes eggs, the brain is an organ that makes sense of nerve signals and a plant’s roots are organs that take in nutrients and moisture.
pancreas: An organ found in the abdomen of animals with backbones. It makes enzymes that are used in the digestion of food. It also makes the hormone insulin, which helps cells in the body use the energy in food.
potassium: A chemical element that occurs as a soft, silver-colored metal. Highly reactive, it burns on contact with air or water with a violet flame. It is found not only in ocean water (including as part of sea salt) but also in many minerals.
primary: An adjective meaning major, first or most important.
protein: A compound made from one or more long chains of amino acids. Proteins are an essential part of all living organisms. They form the basis of living cells, muscle and tissues; they also do the work inside of cells. Antibodies, hemoglobin and enzymes are all examples of proteins. Medicines frequently work by latching onto proteins.
receptor: (in biology) A molecule in cells that serves as a docking station for another molecule. That second molecule can turn on some special activity by the cell.
risk: The chance or mathematical likelihood that some bad thing might happen. For instance, exposure to radiation poses a risk of cancer. Or the hazard — or peril — itself. (For instance: Among cancer risks that the people faced were radiation and drinking water tainted with arsenic.)
saccharin: A no-calorie sugar substitute.
stress: (in biology) A factor — such as unusual temperatures, movements, moisture or pollution — that affects the health of a species or ecosystem. (in psychology) A mental, physical, emotional or behavioral reaction to an event or circumstance (stressor) that disturbs a person or animal’s usual state of being or places increased demands on a person or animal; psychological stress can be either positive or negative.
sucralose: An artificial sugar sold under the brand name Splenda (among other brands). Sucralose is much sweeter than sucrose.
system: A network of parts that together work to achieve some function. For instance, the blood, vessels and heart are primary components of the human body’s circulatory system. Similarly, trains, platforms, tracks, roadway signals and overpasses are among the potential components of a nation’s railway system. System can even be applied to the processes or ideas that are part of some method or ordered set of procedures for getting a task done.
tar: A thick, viscous black flammable goo derived from coal or wood. It consists of a range of hydrocarbons, resins, alcohols and more.
taste: One of the basic properties the body uses to sense its environment, especially foods, using receptors (taste buds) on the tongue (and some other organs).
tissue: Made of cells, it is any of the distinct types of materials that make up animals, plants or fungi. Cells within a tissue work as a unit to perform a particular function in living organisms. Different organs of the human body, for instance, often are made from many different types of tissues.
vitamin: Any of a group of chemicals that are essential for normal growth and nutrition and are required in small quantities in the diet because either they cannot be made by the body or the body cannot easily make them in sufficient amounts to support health.
